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1.  Ethnic Disparities in Diabetes Management and Pay-for-Performance in the UK: The Wandsworth Prospective Diabetes Study 
PLoS Medicine  2007;4(6):e191.
Background
Pay-for-performance rewards health-care providers by paying them more if they succeed in meeting performance targets. A new contract for general practitioners in the United Kingdom represents the most radical shift towards pay-for-performance seen in any health-care system. The contract provides an important opportunity to address disparities in chronic disease management between ethnic and socioeconomic groups. We examined disparities in management of people with diabetes and intermediate clinical outcomes within a multiethnic population in primary care before and after the introduction of the new contract in April 2004.
Methods and Findings
We conducted a population-based longitudinal survey, using electronic general practice records, in an ethnically diverse part of southwest London. Outcome measures were prescribing levels and achievement of national treatment targets (HbA1c ≤ 7.0%; blood pressure [BP] < 140/80 mm Hg; total cholesterol ≤ 5 mmol/l or 193 mg/dl). The proportion of patients reaching treatment targets for HbA1c, BP, and total cholesterol increased significantly after the implementation of the new contract. The extents of these increases were broadly uniform across ethnic groups, with the exception of the black Caribbean patient group, which had a significantly lower improvement in HbA1c (adjusted odds ratio [AOR] 0.75, 95% confidence interval [CI] 0.57–0.97) and BP control (AOR 0.65, 95% CI 0.53–0.81) relative to the white British patient group. Variations in prescribing and achievement of treatment targets between ethnic groups present in 2003 were not attenuated in 2005.
Conclusions
Pay-for-performance incentives have not addressed disparities in the management and control of diabetes between ethnic groups. Quality improvement initiatives must place greater emphasis on minority communities to avoid continued disparities in mortality from cardiovascular disease and the other major complications of diabetes.
Based on a population-based longitudinal survey, Christopher Millett and colleagues concluded that pay-for-performance incentives for UK general practitioners had not addressed disparities in the management and control of diabetes between ethnic groups.
Editors' Summary
Background.
When used in health care, the term “pay-for-performance” means rewarding health-care providers by paying them more if they succeed in meeting performance targets set by the government and other commissioners of health care. It is an approach to health service management that is becoming common, particularly in the US and the UK. For example, the UK's general practitioners (family doctors) agreed with the government in 2004 that they would receive increases to their income that would depend on how well they were judged to be performing according to 146 quality indicators that cover clinical care for ten chronic diseases, as well as “organization of care,” and “patient experience.” One of the chronic diseases is diabetes, a condition that has reached epidemic proportions in the UK, as it has also in many other countries.
  Ethnic minorities often suffer more from health problems than the majority population of the country they live in. They are also likely to be served less well by the health services. Diabetes is a case in point; in many countries—including the US and UK—the condition is much more common in minority groups. In addition, their diabetes is usually less well “managed”—i.e., it becomes more severe more rapidly and there are more complications. In the UK, the government recognizes the need to ensure that its health policies are applied to all sectors of the population, including minority ethnic communities. Nevertheless, the advances that have been made in the management of diabetes have not benefited the UK's ethnic minorities to the same extent as they have the majority population. It is hoped that the use of pay-for-performance management by the UK National Health Service will lead to more efficient delivery of health care, and that one consequence will be that different communities will be more equally served.
Why Was This Study Done?
The researchers wanted to find out whether the introduction of pay-for-performance management in general medical practice in the UK was leading to a reduction in the gap in the quality of care provided to people with diabetes who belonged to ethnic minorities and other people with diabetes.
What Did the Researchers Do and Find?
The research was carried out in Wandsworth, an area of southwest London that is considered to be “ethnically diverse.” Over 4,200 people with diabetes are registered with general practitioners in this area. The researchers used the electronic records kept by these doctors and they focused on diabetes “treatment targets” set by the government, according to which the blood pressure and cholesterol levels of people with diabetes should be kept below defined levels. There is also a target level for glycated hemoglobin (HbA1c), which is a substance that can be used to measure the extent to which a patient's diabetes is under control. The researchers calculated the percentage of patients who were meeting these treatment targets. Overall, more patients met their treatment targets after the introduction of pay-for-performance management than were doing so before. All ethnic groups seemed to have benefited, but the black Caribbean group did not benefit as much as the other groups; the number of these patients who met the targets did improve, but the gap between them and patients with diabetes from other ethnic groups remained about the same.
What Do These Findings Mean?
The researchers concluded that, while the introduction of pay-for-performance did seem to have been beneficial, it had not addressed disparities in the management and control of diabetes between ethnic groups. They say that, in all initiatives to improve the quality of health care, special efforts must be made to reduce such gaps. The UK's use of pay-for-performance in general practice is regarded internationally as a very bold step, but, as other countries are also considering moving in this direction, the lessons from the study will be relevant in many other parts of the world.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0040191.
Wikipedia has an entry on pay-for-performance in health care (note: Wikipedia is a free online encyclopedia that anyone can edit)
Information about how the NHS works in England
Diabetes UK is the largest organization in the UK working for people with diabetes and its website includes a useful Guide to Diabetes
The London Health Observatory is one of nine health observatories set up by the NHS to monitor health and health care in England. There is a page devoted to “ethnic health intelligence”
Introductory information about diabetes as a medical condition may be found on the MedlinePlus website; there are several MedlinePlus pages on diabetes as well
doi:10.1371/journal.pmed.0040191
PMCID: PMC1891316  PMID: 17564486
2.  Effect of social deprivation on blood pressure monitoring and control in England: a survey of data from the quality and outcomes framework 
Objective To determine levels of blood pressure monitoring and control in primary care and to determine the effect of social deprivation on these levels.
Design Retrospective longitudinal survey, 2005 to 2007.
Setting General practices in England.
Participants Data obtained from 8515 practices (99.3% of all practices) in year 1, 8264 (98.3%) in year 2, and 8192 (97.8%) in year 3.
Main outcome measures Blood pressure indicators and chronic disease prevalence estimates contained within the UK quality and outcomes framework; social deprivation scores for each practice, ethnicity data obtained from the 2001 national census; general practice characteristics.
Results In 2005, 82.3% of adults (n=52.8m) had an up to date blood pressure recording; by 2007, this proportion had risen to 88.3% (n=53.2m). Initially, there was a 1.7% gap between mean blood pressure recording levels in practices located in the least deprived fifth of communities compared with the most deprived fifth, but, three years later, this gap had narrowed to 0.2%. Achievement of target blood pressure levels in 2005 for practices located in the least deprived communities ranged from 71.0% (95% CI 70.4% to 71.6%) for diabetes to 85.1% (84.7% to 85.6%) for coronary heart disease; practices in the most deprived communities achieved 68.9% (68.4% to 69.5%) and 81.8 % (81.3% to 82.3%) respectively. Three years later, target achievement in the least deprived practices had risen to 78.6% (78.1% to 79.1%) and 89.4% (89.1% to 89.7%) respectively. Target achievement in the most deprived practices rose similarly, to 79.2% (78.8% to 79.6%) and 88.4% (88.2% to 88.7%) respectively. Similar changes were observed for the achievement of blood pressure targets in hypertension, cerebrovascular disease, and chronic kidney disease.
Conclusions Since the reporting of performance indicators for primary care and the incorporation of pay for performance in 2004, blood pressure monitoring and control have improved substantially. Improvements in achievement have been accompanied by the near disappearance of the achievement gap between least and most deprived areas.
doi:10.1136/bmj.a2030
PMCID: PMC2590907  PMID: 18957697
3.  Hospital Performance, the Local Economy, and the Local Workforce: Findings from a US National Longitudinal Study 
PLoS Medicine  2010;7(6):e1000297.
Blustein and colleagues examine the associations between changes in hospital performance and their local economic resources. Locationally disadvantaged hospitals perform poorly on key indicators, raising concerns that pay-for-performance models may not reduce inequality.
Background
Pay-for-performance is an increasingly popular approach to improving health care quality, and the US government will soon implement pay-for-performance in hospitals nationwide. Yet hospital capacity to perform (and improve performance) likely depends on local resources. In this study, we quantify the association between hospital performance and local economic and human resources, and describe possible implications of pay-for-performance for socioeconomic equity.
Methods and Findings
We applied county-level measures of local economic and workforce resources to a national sample of US hospitals (n = 2,705), during the period 2004–2007. We analyzed performance for two common cardiac conditions (acute myocardial infarction [AMI] and heart failure [HF]), using process-of-care measures from the Hospital Quality Alliance [HQA], and isolated temporal trends and the contributions of individual resource dimensions on performance, using multivariable mixed models. Performance scores were translated into net scores for hospitals using the Performance Assessment Model, which has been suggested as a basis for reimbursement under Medicare's “Value-Based Purchasing” program. Our analyses showed that hospital performance is substantially associated with local economic and workforce resources. For example, for HF in 2004, hospitals located in counties with longstanding poverty had mean HQA composite scores of 73.0, compared with a mean of 84.1 for hospitals in counties without longstanding poverty (p<0.001). Hospitals located in counties in the lowest quartile with respect to college graduates in the workforce had mean HQA composite scores of 76.7, compared with a mean of 86.2 for hospitals in the highest quartile (p<0.001). Performance on AMI measures showed similar patterns. Performance improved generally over the study period. Nevertheless, by 2007—4 years after public reporting began—hospitals in locationally disadvantaged areas still lagged behind their locationally advantaged counterparts. This lag translated into substantially lower net scores under the Performance Assessment Model for hospital reimbursement.
Conclusions
Hospital performance on clinical process measures is associated with the quantity and quality of local economic and human resources. Medicare's hospital pay-for-performance program may exacerbate inequalities across regions, if implemented as currently proposed. Policymakers in the US and beyond may need to take into consideration the balance between greater efficiency through pay-for-performance and socioeconomic equity.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
These days, many people are rewarded for working hard and efficiently by being given bonuses when they reach preset performance targets. With a rapidly aging population and rising health care costs, policy makers in many developed countries are considering ways of maximizing value for money, including rewarding health care providers when they meet targets, under “pay-for-performance.” In the UK, for example, a major pay-for-performance initiative—the Quality and Outcomes Framework—began in 2004. All the country's general practices (primary health care facilities that deal with all medical ailments) now detail their achievements in terms of numerous clinical quality indicators for common chronic conditions (for example, the regularity of blood sugar checks for people with diabetes). They are then rewarded on the basis of these results.
Why Was This Study Done?
In the US, the government is poised to implement a nationwide pay-for-performance program in hospitals within Medicare, the government program that provides health insurance to Americans aged 65 years or older, as well as people with disabilities. However, some observers are concerned about the effect that the proposed pay-for-performance program might have on the distribution of health care resources in the US. Pay-for-performance assumes that health care providers have the economic and human resources that they need to perform or to improve their performance. But, if a hospital's capacity to perform depends on local resources, payment based on performance might worsen existing health care inequalities because hospitals in under-resourced areas might lose funds to hospitals in more affluent regions. In other words, the government might act as a reverse Robin Hood, taking from the poor and giving to the rich. In this study, the researchers examine the association between hospital performance and local economic and human resources, to explore whether this scenario is a plausible result of the pending change in US hospital reimbursement.
What Did the Researchers Do and Find?
US hospitals have voluntarily reported their performance on indicators of clinical care (“process-of-care measures”) for acute myocardial infarction (AMI, heart attack), heart failure (HF), and pneumonia under the Hospital Quality Alliance (HQA) program since 2004. The researchers identified 2,705 hospitals that had fully reported process-of-care measures for AMI and HF in both 2004 and 2007. They then used the “Performance Assessment Model” (a methodology developed by the US Centers for Medicare and Medicaid Services to score hospital performance) to calculate scores for each hospital. Finally, they looked for associations between these scores and measures of the hospital's local economic and human resources such as population poverty levels and the percentage of college graduates in the workforce. Hospital performance was associated with local and economic workforce capacity, they report. Thus, hospitals in counties with longstanding poverty had lower average performance scores for HF and AMI than hospitals in affluent counties. Similarly, hospitals in counties with a low percentage of college graduates in the workforce had lower average performance scores than hospitals in counties where more of the workforce had been to college. Finally, although performance improved generally over the study period, hospitals in disadvantaged areas still lagged behind hospitals in advantaged areas in 2007.
What Do These Findings Mean?
These findings indicate that hospital performance (as measured by the clinical process measures considered here) is associated with the quantity and quality of local human and economic resources. Thus, the proposed Medicare hospital pay-for-performance program may exacerbate existing US health care inequalities by leading to the transfer of funds from hospitals in disadvantaged locations to those in advantaged locations. Although further studies are needed to confirm this conclusion, these findings have important implications for pay-for-performance programs in health care. They suggest that US policy makers may need to modify how they measure performance improvement—the current Performance Assessment Model gives hospitals that start from a low baseline less credit for improvements than those that start from a high baseline. This works against hospitals in disadvantaged locations, which start at a low baseline. Second and more generally, they suggest that there may be a tension between the efficiency goals of pay-for-performance and other equity goals of health care systems. In a world where resources vary across regions, the expectation that regions can perform equally may not be realistic.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000297.
KaiserEDU.org is an online resource for learning about the US health care system. It includes educational modules on such topics as the Medicare program and efforts to improve the quality of care
The Hospital Quality Alliance provides information on the quality of care in US hospitals
Information about the UK National Health Service Quality and Outcomes Framework pay-for-performance initiative for general practice surgeries is available
doi:10.1371/journal.pmed.1000297
PMCID: PMC2893955  PMID: 20613863
4.  Ethnic Disparities in Coronary Heart Disease Management and Pay for Performance in the UK 
Background
Few pay for performance schemes have been subject to rigorous evaluation, and their impact on disparities in chronic disease management is uncertain.
Objective
To examine disparities in coronary heart disease management and intermediate clinical outcomes within a multiethnic population before and after the introduction of a major pay for performance initiative in April 2004.
Design
Comparison of two cross-sectional surveys using electronic general practice records.
Setting
Thirty-two family practices in south London, United Kingdom (UK).
Patients
Two thousand eight hundred and ninety-one individuals with coronary heart disease registered with participating practices in 2003 and 3,101 in 2005.
Measurements
Percentage achievement by ethnic group of quality indicators in the management of coronary heart disease
Results
The proportion of patients reaching national treatment targets increased significantly for blood pressure (51.2% to 58.9%) and total cholesterol (65.7% to 73.8%) after the implementation of a major pay for performance initiative in April 2004. Improvements in blood pressure control were greater in the black group compared to whites, with disparities evident at baseline being attenuated (black 54.8% vs. white 58.3% reaching target in 2005). Lower recording of blood pressure in the south Asian group evident in 2003 was attenuated in 2005. Statin prescribing remained significantly lower ( < 0.001) in the black group compared with the south Asian and white groups after the implementation of pay for performance (black 74.8%, south Asian 83.8%, white 80.2% in 2005).
Conclusions
The introduction of pay for performance incentives in UK primary care has been associated with better and more equitable management of coronary heart disease across ethnic groups.
doi:10.1007/s11606-008-0832-5
PMCID: PMC2607505  PMID: 18953616
pay for performance; coronary heart disease; primary care; ethnicity
5.  Behavioural Interventions for Type 2 Diabetes 
Executive Summary
In June 2008, the Medical Advisory Secretariat began work on the Diabetes Strategy Evidence Project, an evidence-based review of the literature surrounding strategies for successful management and treatment of diabetes. This project came about when the Health System Strategy Division at the Ministry of Health and Long-Term Care subsequently asked the secretariat to provide an evidentiary platform for the Ministry’s newly released Diabetes Strategy.
After an initial review of the strategy and consultation with experts, the secretariat identified five key areas in which evidence was needed. Evidence-based analyses have been prepared for each of these five areas: insulin pumps, behavioural interventions, bariatric surgery, home telemonitoring, and community based care. For each area, an economic analysis was completed where appropriate and is described in a separate report.
To review these titles within the Diabetes Strategy Evidence series, please visit the Medical Advisory Secretariat Web site, http://www.health.gov.on.ca/english/providers/program/mas/mas_about.html,
Diabetes Strategy Evidence Platform: Summary of Evidence-Based Analyses
Continuous Subcutaneous Insulin Infusion Pumps for Type 1 and Type 2 Adult Diabetics: An Evidence-Based Analysis
Behavioural Interventions for Type 2 Diabetes: An Evidence-Based Analysis
Bariatric Surgery for People with Diabetes and Morbid Obesity: An Evidence-Based Summary
Community-Based Care for the Management of Type 2 Diabetes: An Evidence-Based Analysis
Home Telemonitoring for Type 2 Diabetes: An Evidence-Based Analysis
Application of the Ontario Diabetes Economic Model (ODEM) to Determine the Cost-effectiveness and Budget Impact of Selected Type 2 Diabetes Interventions in Ontario
Objective
The objective of this report is to determine whether behavioural interventions1 are effective in improving glycemic control in adults with type 2 diabetes.
Background
Diabetes is a serious chronic condition affecting millions of people worldwide and is the sixth leading cause of death in Canada. In 2005, an estimated 8.8% of Ontario’s population had diabetes, representing more than 816,000 Ontarians. The direct health care cost of diabetes was $1.76 billion in the year 2000 and is projected to rise to a total cost of $3.14 billion by 2016. Much of this cost arises from the serious long-term complications associated with the disease including: coronary heart disease, stroke, adult blindness, limb amputations and kidney disease.
Type 2 diabetes accounts for 90–95% of diabetes and while type 2 diabetes is more prevalent in people aged 40 years and older, prevalence in younger populations is increasing due to a rise in obesity and physical inactivity in children.
Data from the United Kingdom Prospective Diabetes Study (UKPDS) has shown that tight glycemic control can significantly reduce the risk of developing serious complications in type 2 diabetics. Despite physicians’ and patients’ knowledge of the importance of glycemic control, Canadian data has shown that only 38% of patients with diabetes have HbA1C levels in the optimal range of 7% or less. This statistic highlights the complexities involved in the management of diabetes, which is characterized by extensive patient involvement in addition to the support provided by physicians. An enormous demand is, therefore, placed on patients to self-manage the physical, emotional and psychological aspects of living with a chronic illness.
Despite differences in individual needs to cope with diabetes, there is general agreement for the necessity of supportive programs for patient self-management. While traditional programs were didactic models with the goal of improving patients’ knowledge of their disease, current models focus on behavioural approaches aimed at providing patients with the skills and strategies required to promote and change their behaviour.
Several meta-analyses and systematic reviews have demonstrated improved health outcomes with self-management support programs in type 2 diabetics. They have all, however, either looked at a specific component of self-management support programs (i.e. self-management education) or have been conducted in specific populations. Most reviews are also qualitative and do not clearly define the interventions of interest, making findings difficult to interpret. Moreover, heterogeneity in the interventions has led to conflicting evidence on the components of effective programs. There is thus much uncertainty regarding the optimal design and delivery of these programs by policymakers.
Evidence-Based Analysis of Effectiveness
Research Questions
Are behavioural interventions effective in improving glycemic control in adults with type 2 diabetes?
Is the effectiveness of the intervention impacted by intervention characteristics (e.g. delivery of intervention, length of intervention, mode of instruction, interventionist etc.)?
Inclusion Criteria
English Language
Published between January 1996 to August 2008
Type 2 diabetic adult population (>18 years)
Randomized controlled trials (RCTs)
Systematic reviews, or meta-analyses
Describing a multi-faceted self-management support intervention as defined by the 2007 Self-Management Mapping Guide (1)
Reporting outcomes of glycemic control (HbA1c) with extractable data
Studies with a minimum of 6-month follow up
Exclusion Criteria
Studies with a control group other than usual care
Studies with a sample size <30
Studies without a clearly defined intervention
Outcomes of Interest
Primary outcome: glycemic control (HbA1c)
Secondary outcomes: systolic blood pressure (SBP) control, lipid control, change in smoking status, weight change, quality of life, knowledge, self-efficacy, managing psychosocial aspects of diabetes, assessing dissatisfaction and readiness to change, and setting and achieving diabetes goals.
Search Strategy
A search was performed in OVID MEDLINE, MEDLINE In-Process and Other Non-Indexed Citations, EMBASE, the Cumulative Index to Nursing & Allied Health Literature (CINAHL), The Cochrane Library, and the International Agency for Health Technology Assessment (INAHTA) for studies published between January 1996 and August 2008. Abstracts were reviewed by a single author and studies meeting the inclusion criteria outlined above were obtained. Data on population characteristics, glycemic control outcomes, and study design were extracted. Reference lists were also checked for relevant studies. The quality of the evidence was assessed as being either high, moderate, low, or very low according to the GRADE methodology.
Summary of Findings
The search identified 638 citations published between 1996 and August 2008, of which 12 met the inclusion criteria and one was a meta-analysis (Gary et al. 2003). The remaining 11 studies were RCTs (9 were used in the meta-analysis) and only one was defined as small (total sample size N=47).
Summary of Participant Demographics across studies
A total of 2,549 participants were included in the 11 identified studies. The mean age of participants reported was approximately 58 years and the mean duration of diabetes was approximately 6 years. Most studies reported gender with a mean percentage of females of approximately 67%. Of the eleven studies, two focused only on women and four included only Hispanic individuals. All studies evaluated type 2 diabetes patients exclusively.
Study Characteristics
The studies were conducted between 2002 and 2008. Approximately six of 11 studies were carried out within the USA, with the remaining studies conducted in the UK, Sweden, and Israel (sample size ranged from 47 to 824 participants). The quality of the studies ranged from moderate to low with four of the studies being of moderate quality and the remaining seven of low quality (based on the Consort Checklist). Differences in quality were mainly due to methodological issues such as inadequate description of randomization, sample size calculation allocation concealment, blinding and uncertainty of the use of intention-to-treat (ITT) analysis. Patients were recruited from several settings: six studies from primary or general medical practices, three studies from the community (e.g. via advertisements), and two from outpatient diabetes clinics. A usual care control group was reported in nine of 11 of the studies and two studies reported some type of minimal diabetes care in addition to usual care for the control group.
Intervention Characteristics
All of the interventions examined in the studies were mapped to the 2007 Self-management Mapping Guide. The interventions most often focused on problem solving, goal setting and encouraging participants to engage in activities that protect and promote health (e.g. modifying behaviour, change in diet, and increase physical activity). All of the studies examined comprehensive interventions targeted at least two self-care topics (e.g. diet, physical activity, blood glucose monitoring, foot care, etc.). Despite the homogeneity in the aims of the interventions, there was substantial clinical heterogeneity in other intervention characteristics such as duration, intensity, setting, mode of delivery (group vs. individual), interventionist, and outcomes of interest (discussed below).
Duration, Intensity and Mode of Delivery
Intervention durations ranged from 2 days to 1 year, with many falling into the range of 6 to 10 weeks. The rest of the interventions fell into categories of ≤ 2 weeks (2 studies), 6 months (2 studies), or 1 year (3 studies). Intensity of the interventions varied widely from 6 hours over 2 days, to 52 hours over 1 year; however, the majority consisted of interventions of 6 to 15 hours. Both individual and group sessions were used to deliver interventions. Group counselling was used in five studies as a mode of instruction, three studies used both individual and group sessions, and one study used individual sessions as its sole mode of instruction. Three studies also incorporated the use of telephone support as part of the intervention.
Interventionists and Setting
The following interventionists were reported (highest to lowest percentage, categories not mutually exclusive): nurse (36%), dietician (18%), physician (9%), pharmacist (9%), peer leader/community worker (18%), and other (36%). The ‘other’ category included interventionists such as consultants and facilitators with unspecified professional backgrounds. The setting of most interventions was community-based (seven studies), followed by primary care practices (three studies). One study described an intervention conducted in a pharmacy setting.
Outcomes
Duration of follow up of the studies ranged from 6 months to 8 years with a median follow-up duration of 12 months. Nine studies followed up patients at a minimum of two time points. Despite clear reporting of outcomes at follow up time points, there was poor reporting on whether the follow up was measured from participant entry into study or from end of intervention. All studies reported measures of glycemic control, specifically HbA1c levels. BMI was measured in five studies, while body weight was reported in two studies. Cholesterol was examined in three studies and blood pressure reduction in two. Smoking status was only examined in one of the studies. Additional outcomes examined in the trials included patient satisfaction, quality of life, diabetes knowledge, diabetes medication reduction, and behaviour modification (i.e. daily consumption of fruits/vegetables, exercise etc). Meta-analysis of the studies identified a moderate but significant reduction in HbA1c levels -0.44% 95%CI: -0.60, -0.29) for behavioural interventions in comparison to usual care for adults with type 2 diabetes. Subgroup analyses suggested the largest effects in interventions which were of at least duration and interventions in diabetics with higher baseline HbA1c (≥9.0). The quality of the evidence according to GRADE for the overall estimate was moderate and the quality of evidence for the subgroup analyses was identified as low.
Summary of Meta-Analysis of Studies Investigating the Effectiveness of Behavioural Interventions on HbA1c in Patients with Type 2 Diabetes.
Based on one study
Conclusions
Based on moderate quality evidence, behavioural interventions as defined by the 2007 Self-management mapping guide (Government of Victoria, Australia) produce a moderate reduction in HbA1c levels in patients with type 2 diabetes compared with usual care.
Based on low quality evidence, the interventions with the largest effects are those:
- in diabetics with higher baseline HbA1c (≥9.0)
- in which the interventions were of at least 1 year in duration
PMCID: PMC3377516  PMID: 23074526
6.  Pay for perfomance and the quality of diabetes management in individuals with and without co-morbid medical conditions 
Summary
Objective
To examine the impact of the Quality and Outcomes Framework, a major pay-for-performance incentive introduced in the UK during 2004, on diabetes management in patients with and without co-morbidity.
Design
Cohort study comparing actual achievement of treatment targets in 2004 and 2005 with that predicted by the underlying (pre-intervention) trend in diabetes patients with and without co-morbid conditions.
Setting
A total of 422 general practices participating in the General Practice Research Database.
Main outcomes measures
Achievement of diabetes treatment targets for blood pressure (< 140/80 mm Hg), HbA1c (≤ 7.0%) and cholesterol (≤ 5 mmol/L).
Results
The percentage of diabetes patients with co-morbidity reaching blood pressure and cholesterol targets exceeded that predicted by the underlying trend during the first two years of pay for perfomance (by 3.1% [95% CI 1.1–5.1] for BP and 4.1% [95% CI 2.2–6.0] for cholesterol among patients with ≥ 5 co-morbidities in 2005). Similar improvements were evident in patients without co-morbidity, except for cholesterol control in 2004 (−0.2% [95% CI −1.7–1.4]). The percentage of patients meeting the HbA1c target in the first two years of this program was significantly lower than predicted by the underlying trend in all patients, with the greatest shortfall in patients without co-morbidity (3.8% [95% CI 2.6–5.0] lower in 2005). Patients with co-morbidity remained significantly more likely to meet treatment targets for cholesterol and HbA1c than those without after the introduction of pay for perfomance.
Conclusions
Diabetes patients with co-morbid conditions appear to have benefited more from this pay-for-performance program than those without co-morbidity.
doi:10.1258/jrsm.2009.090171
PMCID: PMC2738769  PMID: 19734534
7.  Association of practice size and pay-for-performance incentives with the quality of diabetes management in primary care 
Background:
Not enough is known about the association between practice size and clinical outcomes in primary care. We examined this association between 1997 and 2005, in addition to the impact of the Quality and Outcomes Framework, a pay-for-performance incentive scheme introduced in the United Kingdom in 2004, on diabetes management.
Methods:
We conducted a retrospective open-cohort study using data from the General Practice Research Database. We enrolled 422 general practices providing care for 154 945 patients with diabetes. Our primary outcome measures were the achievement of national treatment targets for blood pressure, glycated hemoglobin (HbA1c) levels and total cholesterol.
Results:
We saw improvements in the recording of process of care measures, prescribing and achieving intermediate outcomes in all practice sizes during the study period. We saw improvement in reaching national targets after the introduction of the Quality and Outcomes Framework. These improvements significantly exceeded the underlying trends in all practice sizes for achieving targets for cholesterol level and blood pressure, but not for HbA1c level. In 1997 and 2005, there were no significant differences between the smallest and largest practices in achieving targets for blood pressure (1997 odds ratio [OR] 0.98, 95% confidence interval [CI] 0.82 to 1.16; 2005 OR 0.92, 95% CI 0.80 to 1.06 in 2005), cholesterol level (1997 OR 0.94, 95% CI 0.76 to 1.16; 2005 OR 1.1, 95% CI 0.97 to 1.40) and glycated hemoglobin level (1997 OR 0.79, 95% CI 0.55 to 1.14; 2005 OR 1.05, 95% CI 0.93 to 1.19).
Interpretation:
We found no evidence that size of practice is associated with the quality of diabetes management in primary care. Pay-for-performance programs appear to benefit both large and small practices to a similar extent.
doi:10.1503/cmaj.101187
PMCID: PMC3168664  PMID: 21810950
8.  Risk of Cardiovascular Disease and Total Mortality in Adults with Type 1 Diabetes: Scottish Registry Linkage Study 
PLoS Medicine  2012;9(10):e1001321.
Helen Colhoun and colleagues report findings from a Scottish registry linkage study regarding contemporary risks for cardiovascular events and all-cause mortality among individuals diagnosed with type 1 diabetes.
Background
Randomized controlled trials have shown the importance of tight glucose control in type 1 diabetes (T1DM), but few recent studies have evaluated the risk of cardiovascular disease (CVD) and all-cause mortality among adults with T1DM. We evaluated these risks in adults with T1DM compared with the non-diabetic population in a nationwide study from Scotland and examined control of CVD risk factors in those with T1DM.
Methods and Findings
The Scottish Care Information-Diabetes Collaboration database was used to identify all people registered with T1DM and aged ≥20 years in 2005–2007 and to provide risk factor data. Major CVD events and deaths were obtained from the national hospital admissions database and death register. The age-adjusted incidence rate ratio (IRR) for CVD and mortality in T1DM (n = 21,789) versus the non-diabetic population (3.96 million) was estimated using Poisson regression. The age-adjusted IRR for first CVD event associated with T1DM versus the non-diabetic population was higher in women (3.0: 95% CI 2.4–3.8, p<0.001) than men (2.3: 2.0–2.7, p<0.001) while the IRR for all-cause mortality associated with T1DM was comparable at 2.6 (2.2–3.0, p<0.001) in men and 2.7 (2.2–3.4, p<0.001) in women. Between 2005–2007, among individuals with T1DM, 34 of 123 deaths among 10,173 who were <40 years and 37 of 907 deaths among 12,739 who were ≥40 years had an underlying cause of death of coma or diabetic ketoacidosis. Among individuals 60–69 years, approximately three extra deaths per 100 per year occurred among men with T1DM (28.51/1,000 person years at risk), and two per 100 per year for women (17.99/1,000 person years at risk). 28% of those with T1DM were current smokers, 13% achieved target HbA1c of <7% and 37% had very poor (≥9%) glycaemic control. Among those aged ≥40, 37% had blood pressures above even conservative targets (≥140/90 mmHg) and 39% of those ≥40 years were not on a statin. Although many of these risk factors were comparable to those previously reported in other developed countries, CVD and mortality rates may not be generalizable to other countries. Limitations included lack of information on the specific insulin therapy used.
Conclusions
Although the relative risks for CVD and total mortality associated with T1DM in this population have declined relative to earlier studies, T1DM continues to be associated with higher CVD and death rates than the non-diabetic population. Risk factor management should be improved to further reduce risk but better treatment approaches for achieving good glycaemic control are badly needed.
Please see later in the article for the Editors' Summary
Editors' Summary
Background. People with diabetes are more likely to have cardiovascular disease such as heart attacks and strokes. They also have a higher risk of dying prematurely from any cause. Controlling blood sugar (glucose), blood pressure, and cholesterol can help reduce these risks. Some people with type 1 diabetes can achieve tight blood glucose control through a strict regimen that includes a carefully calculated diet, frequent physical activity, regular blood glucose testing several times a day, and multiple daily doses of insulin. Other drugs can reduce blood pressure and cholesterol levels. Keeping one's weight in the normal range and not smoking are important ways in which all people, including those with type 1 diabetes can reduce their risks of heart disease and premature death.
Why Was This Study Done? Researchers and doctors have known for almost two decades what patients with type 1 diabetes can do to minimize the complications from the disease and thereby reduce their risks for cardiovascular disease and early death. So for some time now, patients should have been treated and counseled accordingly. This study was done to evaluate the current risks for have cardiovascular disease and premature death amongst people living with type 1 diabetes in a high-income country (Scotland).
What Did the Researchers Do and Find? From a national register of all people with type 1 diabetes in Scotland, the researchers selected those who were older than 20 years and alive at any time from January 2005 to May 2008. This included about 19,000 people who had been diagnosed with type 1 diabetes before 2005. Another 2,600 were diagnosed between 2005 and 2008. They also obtained data on heart attacks and strokes in these patients from hospital records and on deaths from the natural death register. To obtain a good picture of the current relative risks, they compared the patients with type 1 diabetes with the non-diabetic general Scottish population with regard to the risk of heart attacks/strokes and death from all causes. They also collected information on how well the people with diabetes controlled their blood glucose, on their weight, and whether they smoked.
They found that the current risks compared with the general Scottish population are quite a bit lower than those of people with type 1 diabetes in earlier decades. However, people with type 1 diabetes in Scotland still have much higher (more than twice) the risk of heart attacks, strokes, or premature death than the general population. Moreover, the researchers found a high number of deaths in younger people with diabetes from coma—caused by either too much blood sugar (hyperglycemia) or too little (hypoglycemia). Severe hyperglycemia and hypoglycemia happen when blood glucose control is poor. When the scientists looked at test results for HbA1c levels (a test that is done once or twice a year to see how well patients controlled their blood sugar over the previous 3 months) for all patients, they found that the majority of them did not come close to controlling their blood glucose within the recommended range.
When the researchers compared body mass index (a measure of weight that takes height into account) and smoking between the people with type 1 diabetes and the general population, they found similar proportions of smokers and overweight or obese people.
What Do these Findings Mean? The results represent a snapshot of the recent situation regarding complications from type 1 diabetes in the Scottish population. The results suggest that within this population, strategies over the past two decades to reduce complications from type 1 diabetes that cause cardiovascular disease and death are working, in principle. However, there is much need for further improvement. This includes the urgent need to understand why so few people with type 1 diabetes achieve good control of their blood sugar, and what can be done to improve this situation. It is also important to put more effort into keeping people with diabetes from taking up smoking or getting them to quit, as well as preventing them from getting overweight or promoting weight reduction, because this could further reduce the risks of cardiovascular disease and premature death.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001321
National Diabetes Information Clearinghouse, a service of the US National Institute of Diabetes and Digestive and Kidney Diseases, has information on heart disease and diabetes, on general complications of diabetes, and on the HbA1c test (on this site and some others called A1C test) that measures control of blood sugar over the past 3 months
Diabetes.co.uk provides general information on type 1 diabetes, its complications, and what people with the disease can do to reduce their risks
The Canadian Diabetes Association offers a cardiovascular risk self-assessment tool and other relevant information
The American Diabetes Association has information on the benefits and challenges of tight blood sugar control and how it is tested
The Juvenile Diabetes Research Foundation funds research to prevent, cure, and treat type 1 diabetes
Diabetes UK provides extensive information on diabetes for patients, carers, and clinicians
doi:10.1371/journal.pmed.1001321
PMCID: PMC3462745  PMID: 23055834
9.  Performance of small general practices under the UK's Quality and Outcomes Framework 
The British Journal of General Practice  2010;60(578):e335-e344.
Background
Small general practices are often perceived to provide worse care than larger practices.
Aim
To describe the comparative performance of small practices on the UK's pay-for-performance scheme, the Quality and Outcomes Framework.
Design of study
Longitudinal analysis (2004–2005 to 2006–2007) of quality scores for 48 clinical activities.
Setting
Family practices in England (n = 7502).
Method
Comparison of performance of practices by list size, in terms of points scored in the pay-for-performance scheme, reported achievement rates, and population achievement rates (which allow for patients excluded from the scheme).
Results
In the first year of the pay-for-performance scheme, the smallest practices (those with fewer than 2000 patients) had the lowest median reported achievement rates, achieving the clinical targets for 83.8% of eligible patients. Performance generally improved for practices of all sizes over time, but the smallest practices improved at the fastest rate, and by year 3 had the highest median reported achievement rates (91.5%). This improvement was not achieved by additional exception reporting. There was more variation in performance among small practices than larger ones: practices with fewer than 3000 patients (20.1% of all practices in year 3), represented 46.7% of the highest-achieving 5% of practices and 45.1% of the lowest-achieving 5% of practices.
Conclusion
Small practices were represented among both the best and the worst practices in terms of achievement of clinical quality targets. The effect of the pay-for-performance scheme appears to have been to reduce variation in performance, and to reduce the difference between large and small practices.
doi:10.3399/bjgp10X515340
PMCID: PMC2930243  PMID: 20849683
incentives; quality; primary care
10.  Causes of death in Tonga: quality of certification and implications for statistics 
Background
Detailed cause of death data by age group and sex are critical to identify key public health issues and target interventions appropriately. In this study the quality of local routinely collected cause of death data from medical certification is reviewed, and a cause of death profile for Tonga based on amended data is presented.
Methods
Medical certificates of death for all deaths in Tonga for 2001 to 2008 and medical records for all deaths in the main island Tongatapu for 2008 were sought from the national hospital. Cause of death data for 2008 were reviewed for quality through (a) a review of current tabulation procedures and (b) a medical record review. Data from each medical record were extracted and provided to an independent medical doctor to assign cause of death, with underlying cause from the medical record tabulated against underlying cause from the medical certificate. Significant associations in reporting patterns were evaluated and final cause of death for each case in 2008 was assigned based on the best quality information from the medical certificate or medical record. Cause of death data from 2001 to 2007 were revised based on findings from the evaluation of certification of the 2008 data and added to the dataset. Proportional mortality was calculated and applied to age- and sex-specific mortality for all causes from 2001 to 2008. Cause of death was tabulated by age group and sex, and age-standardized (all ages) mortality rates for each sex by cause were calculated.
Results
Reported tabulations of cause of death in Tonga are of immediate cause, with ischemic heart disease and diabetes underrepresented. In the majority of cases the reported (immediate) cause fell within the same broad category as the underlying cause of death from the medical certificate. Underlying cause of death from the medical certificate, attributed to neoplasms, diabetes, and cardiovascular disease were assigned to other underlying causes by the medical record review in 70% to 77% of deaths. Of the 28 (6.5%) deaths attributed to nonspecific or unknown causes on the medical certificate, 17 were able to be attributed elsewhere following review of the medical record. Final cause of death tabulations for 2001 to 2008 demonstrate that noncommunicable diseases are leading adult mortality, and age-standardized rates for cardiovascular diseases, neoplasms, and diabetes increased significantly between 2001 to 2004 and 2005 to 2008. Cause of death data for 2001 to 2008 show increasing cause-specific mortality (deaths per 100,000) from 2001-2004 to 2005-2008 from cardiovascular (194-382 to 423-644 in 2005-2008 for males and 108-227 to 194-321 for females) and other noncommunicable diseases that cannot be accounted for by changes in the age structure of the population. Mortality from diabetes for 2005 to 2008 is estimated at 94 to 222 deaths per 100,000 population for males and 98 to 190 for females (based on the range of plausible all-cause mortality estimates) compared with 2008 estimates from the global burden of disease study of 40 (males) and 53 (females) deaths per 100,000 population.
Discussion
Certification of death was generally found to be the most reliable data on cause of death in Tonga available for Tonga, with 93% of the final assigned causes following review of the 2008 data matching those listed on the medical certificate of death. Cause of death data available in Tonga can be improved by routinely tabulating data by underlying cause and ensuring contributory causes are not recorded in Part I of the certificate during data entry to the database. There is significantly more data on cause of death available in Tonga than are routinely reported or known to international agencies.
doi:10.1186/1478-7954-10-4
PMCID: PMC3378436  PMID: 22390221
Mortality; Cause of death; Noncommunicable Diseases; Medical record review; Death Certification; Tonga; Pacific Islands
11.  Reviewing progress: 7 year trends in characteristics of adults and children enrolled at HIV care and treatment clinics in the United Republic of Tanzania 
BMC Public Health  2013;13:1016.
Background
To evaluate the on-going scale-up of HIV programs, we assessed trends in patient characteristics at enrolment and ART initiation over 7 years of implementation.
Methods
Data were from Optimal Models, a prospective open cohort study of HIV-infected (HIV+) adults (≥15 years) and children (<15 years) enrolled from January 2005 to December 2011 at 44 HIV clinics in 3 regions of mainland Tanzania (Kagera, Kigoma, Pwani) and Zanzibar. Comparative statistics for trends in characteristics of patients enrolled in 2005–2007, 2008–2009 and 2010–2011 were examined.
Results
Overall 62,801 HIV + patients were enrolled: 58,102(92.5%) adults, (66.5% female); 4,699(7.5%) children.
Among adults, pregnant women enrolment increased: 6.8%, 2005–2007; 12.1%, 2008–2009; 17.2%, 2010–2011; as did entry into care from prevention of mother-to-child HIV transmission (PMTCT) programs: 6.6%, 2005–2007; 9.5%, 2008–2009; 12.6%, 2010–2011
. WHO stage IV at enrolment declined: 27.1%, 2005–2007; 20.2%, 2008–2009; 11.1% 2010–2011. Of the 42.5% and 29.5% with CD4+ data at enrolment and ART initiation respectively, median CD4+ count increased: 210 cells/μL, 2005–2007; 262 cells/μL, 2008–2009; 266 cells/μL 2010–2011; but median CD4+ at ART initiation did not change (148 cells/μL overall). Stavudine initiation declined: 84.9%, 2005–2007; 43.1%, 2008–2009; 19.7%, 2010–2011.
Among children, median age (years) at enrolment decreased from 6.1(IQR:2.7-10.0) in 2005–2007 to 4.8(IQR:1.9-8.6) in 2008–2009, and 4.1(IQR:1.5-8.1) in 2010–2011 and children <24 months increased from 18.5% to 26.1% and 31.5% respectively. Entry from PMTCT was 7.0%, 2005–2007; 10.7%, 2008–2009; 15.0%, 2010–2011. WHO stage IV at enrolment declined from 22.9%, 2005–2007, to 18.3%, 2008–2009 to 13.9%, 2010–2011. Proportion initiating stavudine was 39.8% 2005–2007; 39.5%, 2008–2009; 26.1%, 2010–2011. Median age at ART initiation also declined significantly.
Conclusions
Over time, the proportion of pregnant women and of adults and children enrolled from PMTCT programs increased. There was a decline in adults and children with advanced HIV disease at enrolment and initiation of stavudine. Pediatric age at enrolment and ART initiation declined. Results suggest HIV program maturation from an emergency response.
doi:10.1186/1471-2458-13-1016
PMCID: PMC3937235  PMID: 24160907
ART program; HIV-infected adults; HIV-infected children; Trends at enrolment; Trends at ART initiation; Tanzania
12.  Trends in the Prevalence, Awareness, Treatment and Control of High Low Density Lipoprotein-Cholesterol among US Adults from 1999–2000 through 2009–2010 
The American journal of cardiology  2013;112(5):664-670.
Marked increases in the awareness, treatment and control of high LDL-cholesterol occurred among US adults between 1988–1994 and 1999–2004. An update to the ATP-III guidelines was published in 2004 and it is unknown if these improvements have continued following publication of these revised treatment recommendations. We determined trends in the awareness, treatment and control of high LDL-cholesterol among US adults from 1999– 2000 through 2009–2010 using nationally representative samples of US adults ≥ 20 years of age from six consecutive National Health and Nutrition Examination Surveys (NHANES) in 1999–2000 (n=1,659), 2001–2002 (n=1,897), 2003–2004 (n=1,698), 2005–2006 (n=1,692), 2007–2008 (n=2,044) and 2009–2010 (n=2,318). LDL-cholesterol was measured after an overnight fast and high LDL-cholesterol and controlled LDL-cholesterol were defined using the 2004 updated ATP-III guidelines. Awareness and treatment of high cholesterol were defined using self-report. Among US adults, the prevalence of high LDL-cholesterol did not change from 1999–2000 (37.2%) through 2009–2010 (37.8%). Awareness of high LDLcholesterol increased from 48.9% in 1999–2000 to 62.8% in 2003–2004 but did not increase further through 2009–2010 (61.5%). Among those aware of having high LDL-cholesterol, treatment increased from 41.3% in 1999–2000 to 72.6% in 2007–2008 and was 70.0% in 2009–2010. Among US adults receiving treatment for high LDL-cholesterol, the percentage with controlled LDL-cholesterolincreased from 45.0% in 1999–2000 to 65.3% in 2005–2006 and decreased slightly by 2009–2010 (63.6%). High LDL-cholesterol remains common among US adults. Additional efforts are needed to prevent high LDL-cholesterol and increase the awareness, treatment and control of high LDL-cholesterol among US adults.
doi:10.1016/j.amjcard.2013.04.041
PMCID: PMC3769104  PMID: 23726177
LDL-cholesterol; statins; treatment; awareness; risk factors
13.  Impact of pay for performance on quality of chronic disease management by social class group in England 
Summary
Objective
To examine associations between social class and achievement of selected national audit targets for coronary heart disease (CHD), diabetes and hypertension in England before and after the introduction of a major pay for performance programme in 2004.
Design
Secondary analysis of 2003 and 2006 national survey data for respondents with CHD and diabetes and hypertension.
Setting
England.
Main outcome measure
Achievement of national audit targets for blood pressure, blood glucose and cholesterol control.
Results
There were no significant differences in achievement of blood pressure targets in individuals from manual and non-manual occupational groups with diabetes (2003: 65.9% v 60.3%, 2006: 67.6% v 69.7%) or hypertension (2003: 66.2% v 66.2%, 2006: 72.8% v 71.9%) before or after the introduction of pay for performance. Achievement of the cholesterol target was also similar in individuals from manual and non-manual groups with diabetes (2003: 52.5% v 46.6%, 2006: 68.7% v 70.5%) or CHD (2003: 54.3% v 53.3%, 2006: 68.6% v 71.3%). Differences in achievement of the blood pressure target in CHD [75.8% v 84.5%; AOR 0.44 (0.21-0.90)] were evident between manual and non-manual occupational groups after the introduction of pay for performance.
Conclusion
The quality of chronic disease management in England was broadly equitable between socioeconomic groups before this major pay for performance programme and remained so after its introduction.
doi:10.1258/jrsm.2009.080389
PMCID: PMC2746849  PMID: 19297651
14.  Information from Pharmaceutical Companies and the Quality, Quantity, and Cost of Physicians' Prescribing: A Systematic Review 
PLoS Medicine  2010;7(10):e1000352.
Geoff Spurling and colleagues report findings of a systematic review looking at the relationship between exposure to promotional material from pharmaceutical companies and the quality, quantity, and cost of prescribing. They fail to find evidence of improvements in prescribing after exposure, and find some evidence of an association with higher prescribing frequency, higher costs, or lower prescribing quality.
Background
Pharmaceutical companies spent $57.5 billion on pharmaceutical promotion in the United States in 2004. The industry claims that promotion provides scientific and educational information to physicians. While some evidence indicates that promotion may adversely influence prescribing, physicians hold a wide range of views about pharmaceutical promotion. The objective of this review is to examine the relationship between exposure to information from pharmaceutical companies and the quality, quantity, and cost of physicians' prescribing.
Methods and Findings
We searched for studies of physicians with prescribing rights who were exposed to information from pharmaceutical companies (promotional or otherwise). Exposures included pharmaceutical sales representative visits, journal advertisements, attendance at pharmaceutical sponsored meetings, mailed information, prescribing software, and participation in sponsored clinical trials. The outcomes measured were quality, quantity, and cost of physicians' prescribing. We searched Medline (1966 to February 2008), International Pharmaceutical Abstracts (1970 to February 2008), Embase (1997 to February 2008), Current Contents (2001 to 2008), and Central (The Cochrane Library Issue 3, 2007) using the search terms developed with an expert librarian. Additionally, we reviewed reference lists and contacted experts and pharmaceutical companies for information. Randomized and observational studies evaluating information from pharmaceutical companies and measures of physicians' prescribing were independently appraised for methodological quality by two authors. Studies were excluded where insufficient study information precluded appraisal. The full text of 255 articles was retrieved from electronic databases (7,185 studies) and other sources (138 studies). Articles were then excluded because they did not fulfil inclusion criteria (179) or quality appraisal criteria (18), leaving 58 included studies with 87 distinct analyses. Data were extracted independently by two authors and a narrative synthesis performed following the MOOSE guidelines. Of the set of studies examining prescribing quality outcomes, five found associations between exposure to pharmaceutical company information and lower quality prescribing, four did not detect an association, and one found associations with lower and higher quality prescribing. 38 included studies found associations between exposure and higher frequency of prescribing and 13 did not detect an association. Five included studies found evidence for association with higher costs, four found no association, and one found an association with lower costs. The narrative synthesis finding of variable results was supported by a meta-analysis of studies of prescribing frequency that found significant heterogeneity. The observational nature of most included studies is the main limitation of this review.
Conclusions
With rare exceptions, studies of exposure to information provided directly by pharmaceutical companies have found associations with higher prescribing frequency, higher costs, or lower prescribing quality or have not found significant associations. We did not find evidence of net improvements in prescribing, but the available literature does not exclude the possibility that prescribing may sometimes be improved. Still, we recommend that practitioners follow the precautionary principle and thus avoid exposure to information from pharmaceutical companies.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
A prescription drug is a medication that can be supplied only with a written instruction (“prescription”) from a physician or other licensed healthcare professional. In 2009, 3.9 billion drug prescriptions were dispensed in the US alone and US pharmaceutical companies made US$300 billion in sales revenue. Every year, a large proportion of this revenue is spent on drug promotion. In 2004, for example, a quarter of US drug revenue was spent on pharmaceutical promotion. The pharmaceutical industry claims that drug promotion—visits from pharmaceutical sales representatives, advertisements in journals and prescribing software, sponsorship of meetings, mailed information—helps to inform and educate healthcare professionals about the risks and benefits of their products and thereby ensures that patients receive the best possible care. Physicians, however, hold a wide range of views about pharmaceutical promotion. Some see it as a useful and convenient source of information. Others deny that they are influenced by pharmaceutical company promotion but claim that it influences other physicians. Meanwhile, several professional organizations have called for tighter control of promotional activities because of fears that pharmaceutical promotion might encourage physicians to prescribe inappropriate or needlessly expensive drugs.
Why Was This Study Done?
But is there any evidence that pharmaceutical promotion adversely influences prescribing? Reviews of the research literature undertaken in 2000 and 2005 provide some evidence that drug promotion influences prescribing behavior. However, these reviews only partly assessed the relationship between information from pharmaceutical companies and prescribing costs and quality and are now out of date. In this study, therefore, the researchers undertake a systematic review (a study that uses predefined criteria to identify all the research on a given topic) to reexamine the relationship between exposure to information from pharmaceutical companies and the quality, quantity, and cost of physicians' prescribing.
What Did the Researchers Do and Find?
The researchers searched the literature for studies of licensed physicians who were exposed to promotional and other information from pharmaceutical companies. They identified 58 studies that included a measure of exposure to any type of information directly provided by pharmaceutical companies and a measure of physicians' prescribing behavior. They then undertook a “narrative synthesis,” a descriptive analysis of the data in these studies. Ten of the studies, they report, examined the relationship between exposure to pharmaceutical company information and prescribing quality (as judged, for example, by physician drug choices in response to clinical vignettes). All but one of these studies suggested that exposure to drug company information was associated with lower prescribing quality or no association was detected. In the 51 studies that examined the relationship between exposure to drug company information and prescribing frequency, exposure to information was associated with more frequent prescribing or no association was detected. Thus, for example, 17 out of 29 studies of the effect of pharmaceutical sales representatives' visits found an association between visits and increased prescribing; none found an association with less frequent prescribing. Finally, eight studies examined the relationship between exposure to pharmaceutical company information and prescribing costs. With one exception, these studies indicated that exposure to information was associated with a higher cost of prescribing or no association was detected. So, for example, one study found that physicians with low prescribing costs were more likely to have rarely or never read promotional mail or journal advertisements from pharmaceutical companies than physicians with high prescribing costs.
What Do These Findings Mean?
With rare exceptions, these findings suggest that exposure to pharmaceutical company information is associated with either no effect on physicians' prescribing behavior or with adverse affects (reduced quality, increased frequency, or increased costs). Because most of the studies included in the review were observational studies—the physicians in the studies were not randomly selected to receive or not receive drug company information—it is not possible to conclude that exposure to information actually causes any changes in physician behavior. Furthermore, although these findings provide no evidence for any net improvement in prescribing after exposure to pharmaceutical company information, the researchers note that it would be wrong to conclude that improvements do not sometimes happen. The findings support the case for reforms to reduce negative influence to prescribing from pharmaceutical promotion.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000352.
Wikipedia has pages on prescription drugs and on pharmaceutical marketing (note that Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)
The UK General Medical Council provides guidelines on good practice in prescribing medicines
The US Food and Drug Administration provides information on prescription drugs and on its Bad Ad Program
Healthy Skepticism is an international nonprofit membership association that aims to improve health by reducing harm from misleading health information
The Drug Promotion Database was developed by the World Health Organization Department of Essential Drugs & Medicines Policy and Health Action International Europe to address unethical and inappropriate drug promotion
doi:10.1371/journal.pmed.1000352
PMCID: PMC2957394  PMID: 20976098
15.  Trends in utilization of lipid- and blood pressure-lowering agents and goal attainment among the U.S. diabetic population, 1999-2008 
Background
For patients with diabetes, clinical practice guidelines recommend treating to a low-density lipoprotein cholesterol (LDL-C) goal of <2.59 mmol/L (100 mg/dL) and a blood pressure (BP) target of <130/80 mmHg. This analysis assessed recent trends in the utilization of lipid-lowering and BP-lowering agents, as well as LDL-C and BP goal attainment, in the U.S. adult diabetic population.
Methods
9,167 men and nonpregnant women aged ≥20 years were identified from the fasting subsample of the 1999-2008 National Health and Nutritional Examination Survey. Diabetes was identified in 1,214 participants by self report, self-reported use of insulin or oral medications for diabetes, or fasting glucose ≥6.99 mmol/L (126 mg/dL).
Results
The prevalence of diagnosed or undiagnosed diabetes increased significantly over the past decade, from 7.4% in 1999-2000 to 11.9% in 2007-2008 (P = 0.0007). During this period, the use of lipid-lowering agents by participants with diabetes increased from 19.5% to 42.2% (P < 0.0001), and the proportion at LDL-C goal increased from 29.7% to 54.4% (P < 0.0001). Although there was a significant increase in antihypertensive medication use (from 35.4% to 58.9%; P < 0.0001), there was no significant change in the proportion of participants at BP goal (from 47.6% to 55.1%; P = 0.1333) or prevalence of hypertension (from 66.6% to 74.2%; P = 0.3724).
Conclusions
The proportion of diabetic individuals taking lipid- and BP-lowering agents has increased significantly in recent years. However, while there has been a significant improvement in LDL-C goal attainment, nearly one-half of all U.S. adults with diabetes are not at recommended LDL-C or BP treatment goals.
doi:10.1186/1475-2840-10-31
PMCID: PMC3098774  PMID: 21496321
16.  The Effects of Pay for Performance on Disparities in Stroke, Hypertension, and Coronary Heart Disease Management: Interrupted Time Series Study 
PLoS ONE  2011;6(12):e27236.
Background
The Quality and Outcomes Framework (QOF), a major pay-for-performance programme, was introduced into United Kingdom primary care in April 2004. The impact of this programme on disparities in health care remains unclear. This study examines the following questions: has this pay for performance programme improved the quality of care for coronary heart disease, stroke and hypertension in white, black and south Asian patients? Has this programme reduced disparities in the quality of care between these ethnic groups? Did general practices with different baseline performance respond differently to this programme?
Methodology/Principal Findings
Retrospective cohort study of patients registered with family practices in Wandsworth, London during 2007. Segmented regression analysis of interrupted time series was used to take into account the previous time trend. Primary outcome measures were mean systolic and diastolic blood pressure, and cholesterol levels. Our findings suggest that the implementation of QOF resulted in significant short term improvements in blood pressure control. The magnitude of benefit varied between ethnic groups with a statistically significant short term reduction in systolic BP in white and black but not in south Asian patients with hypertension. Disparities in risk factor control were attenuated only on few measures and largely remained intact at the end of the study period.
Conclusions/Significance
Pay for performance programmes such as the QOF in the UK should set challenging but achievable targets. Specific targets aimed at reducing ethnic disparities in health care may also be needed.
doi:10.1371/journal.pone.0027236
PMCID: PMC3240616  PMID: 22194781
17.  Withdrawing performance indicators: retrospective analysis of general practice performance under UK Quality and Outcomes Framework 
Objectives To investigate the effect of withdrawing incentives on recorded quality of care, in the context of the UK Quality and Outcomes Framework pay for performance scheme.
Design Retrospective longitudinal study.
Setting Data for 644 general practices, from 2004/05 to 2011/12, extracted from the Clinical Practice Research Datalink.
Participants All patients registered with any of the practices over the study period—13 772 992 in total.
Intervention Removal of financial incentives for aspects of care for patients with asthma, coronary heart disease, diabetes, stroke, and psychosis.
Main outcome measures Performance on eight clinical quality indicators withdrawn from a national incentive scheme: influenza immunisation (asthma) and lithium treatment monitoring (psychosis), removed in April 2006; blood pressure monitoring (coronary heart disease, diabetes, stroke), cholesterol concentration monitoring (coronary heart disease, diabetes), and blood glucose monitoring (diabetes), removed in April 2011. Multilevel mixed effects multiple linear regression models were used to quantify the effect of incentive withdrawal.
Results Mean levels of performance were generally stable after the removal of the incentives, in both the short and long term. For the two indicators removed in April 2006, levels in 2011/12 were very close to 2005/06 levels, although a small but statistically significant drop was estimated for influenza immunisation. For five of the six indicators withdrawn from April 2011, no significant effect on performance was seen following removal and differences between predicted and observed scores were small. Performance on related outcome indicators retained in the scheme (such as blood pressure control) was generally unaffected.
Conclusions Following the removal of incentives, levels of performance across a range of clinical activities generally remained stable. This indicates that health benefits from incentive schemes can potentially be increased by periodically replacing existing indicators with new indicators relating to alternative aspects of care. However, all aspects of care investigated remained indirectly or partly incentivised in other indicators, and further work is needed to assess the generalisability of the findings when incentives are fully withdrawn.
doi:10.1136/bmj.g330
PMCID: PMC3903315  PMID: 24468469
18.  Protein localization as a principal feature of the etiology and comorbidity of genetic diseases 
Proteins localized within the same subcellular compartment tend to be functionally associated. This study shows that subcellular localization and network distance between disease-associated proteins provide complementary information explaining patterns of disease comorbidity.
A positive correlation was found between subcellular localization of disease-associated protein pairs and measures of comorbidity.A higher comorbidity tendency was found for disease-associated protein pairs that are positioned within a shorter distance in the protein interaction network.The integration of subcellular localization information with protein interaction network sheds light onto the potential molecular connections underlying comorbidity patterns and will help to understand the mechanisms of human disease.
It was shown that the emergence of phenotypically similar diseases are triggered as a result of molecular connections between disease-causing genes (Oti and Brunner, 2007; Zaghloul and Katsanis, 2010). From a genetics, perspective diseases are associated with certain genes (Goh et al, 2007; Feldman et al, 2008), whereas from a proteomics perspective phenotypically similar diseases are connected via biological modules such as protein–protein interactions (PPIs) or molecular pathways (Lage et al, 2007; Jiang et al, 2008; Wu et al, 2008; Linghu et al, 2009; Suthram et al, 2010). These molecular connections between diseases were observed on the population level as well: diseases connected through molecular connections such as shared genes, PPIs, and metabolic pathways tend to show elevated comorbidity (Rzhetsky et al, 2007; Lee et al, 2008; Zhernakova et al, 2009; Park et al, 2009a, 2009b). While these findings constitute a step toward improving our understanding of the mechanism of disease progression, there are still many more molecule-level connections between disease pairs that need to be explored in order to establish a firmer comorbidity association.
Subcellular localization provides spatial information of proteins in the cell; proteins target subcellular localizations to interact with appropriate partners and form functional complexes in signaling pathways and metabolic processes (Au et al, 2007). Abnormal protein localizations are known to lead to the loss of functional effects in diseases (Luheshi et al, 2008; Laurila and Vihinen, 2009). For example, mis-localizations of nuclear/cytoplasmic transport have been detected in many types of carcinoma cells (Kau et al, 2004). A proper identification of protein subcellular localization can hence be useful in discovering disease-associated proteins (Giallourakis et al, 2005; Calvo and Mootha, 2010). With this understanding, we postulate that disease-associated proteins connected by subcellular localizations could also explain the phenotypic similarities between diseases. Furthermore, such connections may also couple to disease progressions that contribute to multiple disease manifestation, that is, comorbidity.
Protein subcellular localization has been extensively studied through various methods to determine a variety of protein functions. To the best of our knowledge, the connection between diseases and subcellular localizations are yet to be studied systematically. To resolve this we constructed, for the first time, a human Disease-associated Protein and subcellular Localization (DPL) matrix (top panel in Box 1). Our DPL matrix provides the ‘cellular localization map of diseases' that represents the spatial index of diseases in the cell. We found that each disease shows unique characteristics of subcellular localization profile in the DPL matrix. We were interested in determining whether subsets of 1284 human diseases exhibit distinct enrichment profiles across subcellular localizations. We calculated pairwise correlations and performed a hierarchical clustering of the enrichments of the 1284 diseases across 10 different subcellular localizations.
Our DPL matrix revealed that 778 diseases (∼62%, P=1.40 × 10−3) are enriched in a single localization and 273 diseases (∼21%, P=3.45 × 10−3) are enriched in dual localizations. In the DPL matrix, certain disease-associated proteins are likely to be found in membrane-bounded organelles such as mitochondria, lysosome, and peroxisome, indicating that the mutations of proteins localized to these compartments are connected to the pathophysiological conditions of those organelles. Meanwhile, certain disease-associated proteins in the DPL matrix are enriched in dual localizations, such as extracellular/plasma membrane or endoplasmic reticulum/Golgi. Although these two pairs of subcellular localizations appear to be distinct compartments at first, they are functionally related compartments in close proximity during protein translocation process in the cell, and thus are likely to share interacting protein partners (Gandhi et al, 2006).
Comorbidity represents the co-occurrence of multiple diseases in the same individual (Lee et al, 2008; Hidalgo et al, 2009; Park et al, 2009a). Many comorbid disease pairs have been shown to share common genes in the human disease network. For example, Diabetes and Alzheimer's disease share a risk factor in angiotensin I converting enzyme, and frequently occur together in an individual. In such instances, comorbidity can be partially attributed to the disease connections on the molecular level. To explore the impact of protein subcellular localization on comorbidity, we hypothesized that certain disease pairs could also be connected via subcellular localization by the molecular connections between the disease-associated proteins (bottom panel in Box 1).
We found a positive correlation between subcellular localization similarity and relative risk (Figure 3B, Pearson's correlation coefficient between relative risk and subcellular localization similarity=0.81, P=2.96 × 10−5). The subcellular localization similarity represents the correlation of subcellular localization profiles between disease pairs. To our surprise, when we compared the relative risk of disease pairs linked via various molecular connections, we found that disease pairs connected by subcellular localization showed a near three-fold higher comorbidity tendency (with link distances equal to 2 or 3) when compared with random pairs (Figure 3E).
We then assessed quantitatively the impact of network distances and subcellular localizations on the comorbidity tendency of disease pairs. We expected the proteins associated with comorbid disease pairs to be located closely in the protein interaction network via fewer links compared with random disease pairs. Indeed, a higher comorbidity tendency was found when two disease-associated proteins were positioned within a shorter distance (gray plots in Figure 3F). Moreover, when subcellular localization information was combined with small network distances, the comorbidity tendency increased dramatically (orange plots in Figure 3F). It suggests that subcellular localization and close network distances, two conceptually distinct molecular connections, contributed synergistically to the comorbidity tendency.
Disease progression is not restricted to the mutation of disease-causing genes, but also affected by molecular connections in ‘disease modules,' resulting in comorbidity (Fraser, 2006; Lee et al, 2008). In this study, for the first time we applied subcellular localization information to elucidate the molecular connections between comorbid diseases. We believe that, based on our finding, our approach helps to define the boundaries of ‘disease modules.' Taken together, integration of diverse molecular connections should improve the molecular level understanding of hitherto unexplained comorbid disease pairs and help us in expanding the scope of our knowledge of the mechanism of human disease progression.
Proteins targeting the same subcellular localization tend to participate in mutual protein–protein interactions (PPIs) and are often functionally associated. Here, we investigated the relationship between disease-associated proteins and their subcellular localizations, based on the assumption that protein pairs associated with phenotypically similar diseases are more likely to be connected via subcellular localization. The spatial constraints from subcellular localization significantly strengthened the disease associations of the proteins connected by subcellular localizations. In particular, certain disease types were more prevalent in specific subcellular localizations. We analyzed the enrichment of disease phenotypes within subcellular localizations, and found that there exists a significant correlation between disease classes and subcellular localizations. Furthermore, we found that two diseases displayed high comorbidity when disease-associated proteins were connected via subcellular localization. We newly explained 7584 disease pairs by using the context of protein subcellular localization, which had not been identified using shared genes or PPIs only. Our result establishes a direct correlation between protein subcellular localization and disease association, and helps to understand the mechanism of human disease progression.
doi:10.1038/msb.2011.29
PMCID: PMC3130560  PMID: 21613983
cellular networks; comorbidity; human disease; subcellular localization
19.  "Mind the gap!" Evaluation of the performance gap attributable to exception reporting and target thresholds in the new GMS contract: National database analysis 
Background
The 2003 revision of the UK GMS contract rewards general practices for performance against clinical quality indicators. Practices can exempt patients from treatment, and can receive maximum payment for less than full coverage of eligible patients. This paper aims to estimate the gap between the percentage of maximum incentive gained and the percentage of patients receiving indicated care (the pay-performance gap), and to estimate how much of the gap is attributable respectively to thresholds and to exception reporting.
Methods
Analysis of Quality Outcomes Framework data in the National Primary Care Database and exception reporting data from the Information Centre from 8407 practices in England in 2005 – 6. The main outcome measures were the gap between the percentage of maximum incentive gained and the percentage of patients receiving indicated care at the practice level, both for individual indicators and a combined composite score. An additional outcome was the percentage of that gap attributable respectively to exception reporting and maximum threshold targets set at less than 100%.
Results
The mean pay-performance gap for the 65 aggregated clinical indicators was 13.3% (range 2.9% to 48%). 52% of this gap (6.9% of eligible patients) is attributable to thresholds being set at less than 100%, and 48% to patients being exception reported. The gap was greater than 25% in 9 indicators: beta blockers and cholesterol control in heart disease; cholesterol control in stroke; influenza immunization in asthma; blood pressure, sugar and cholesterol control in diabetes; seizures in epilepsy and treatment of hypertension.
Conclusion
Threshold targets and exception reporting introduce an incentive ceiling, which substantially reduces the percentage of eligible patients that UK practices need to treat in order to receive maximum incentive payments for delivering that care. There are good clinical reasons for exception reporting, but after unsuitable patients have been exempted from treatment, there is no reason why all maximum thresholds should not be 100%, whilst retaining the current lower thresholds to provide incentives for lower performing practices.
doi:10.1186/1472-6963-8-131
PMCID: PMC2442837  PMID: 18559086
20.  Effect of pay for performance on the management and outcomes of hypertension in the United Kingdom: interrupted time series study 
Objective To assess the impact of a pay for performance incentive on quality of care and outcomes among UK patients with hypertension in primary care.
Design Interrupted time series.
Setting The Health Improvement Network (THIN) database, United Kingdom.
Participants 470 725 patients with hypertension diagnosed between January 2000 and August 2007.
Intervention The UK pay for performance incentive (the Quality and Outcomes Framework), which was implemented in April 2004 and included specific targets for general practitioners to show high quality care for patients with hypertension (and other diseases).
Main outcome measures Centiles of systolic and diastolic blood pressures over time, rates of blood pressure monitoring, blood pressure control, and treatment intensity at monthly intervals for baseline (48 months) and 36 months after the implementation of pay for performance. Cumulative incidence of major hypertension related outcomes and all cause mortality for subgroups of newly treated (treatment started six months before pay for performance) and treatment experienced (started treatment in year before January 2001) patients to examine different stages of illness.
Results After accounting for secular trends, no changes in blood pressure monitoring (level change 0.85, 95% confidence interval −3.04 to 4.74, P=0.669 and trend change −0.01, −0.24 to 0.21, P=0.615), control (−1.19, −2.06 to 1.09, P=0.109 and −0.01, −0.06 to 0.03, P=0.569), or treatment intensity (0.67, −1.27 to 2.81, P=0.412 and 0.02, −0.23 to 0.19, P=0.706) were attributable to pay for performance. Pay for performance had no effect on the cumulative incidence of stroke, myocardial infarction, renal failure, heart failure, or all cause mortality in both treatment experienced and newly treated subgroups.
Conclusions Good quality of care for hypertension was stable or improving before pay for performance was introduced. Pay for performance had no discernible effects on processes of care or on hypertension related clinical outcomes. Generous financial incentives, as designed in the UK pay for performance policy, may not be sufficient to improve quality of care and outcomes for hypertension and other common chronic conditions.
doi:10.1136/bmj.d108
PMCID: PMC3026849  PMID: 21266440
21.  Clinical Utility of Vitamin D Testing 
Executive Summary
This report from the Medical Advisory Secretariat (MAS) was intended to evaluate the clinical utility of vitamin D testing in average risk Canadians and in those with kidney disease. As a separate analysis, this report also includes a systematic literature review of the prevalence of vitamin D deficiency in these two subgroups.
This evaluation did not set out to determine the serum vitamin D thresholds that might apply to non-bone health outcomes. For bone health outcomes, no high or moderate quality evidence could be found to support a target serum level above 50 nmol/L. Similarly, no high or moderate quality evidence could be found to support vitamin D’s effects in non-bone health outcomes, other than falls.
Vitamin D
Vitamin D is a lipid soluble vitamin that acts as a hormone. It stimulates intestinal calcium absorption and is important in maintaining adequate phosphate levels for bone mineralization, bone growth, and remodelling. It’s also believed to be involved in the regulation of cell growth proliferation and apoptosis (programmed cell death), as well as modulation of the immune system and other functions. Alone or in combination with calcium, Vitamin D has also been shown to reduce the risk of fractures in elderly men (≥ 65 years), postmenopausal women, and the risk of falls in community-dwelling seniors. However, in a comprehensive systematic review, inconsistent results were found concerning the effects of vitamin D in conditions such as cancer, all-cause mortality, and cardiovascular disease. In fact, no high or moderate quality evidence could be found concerning the effects of vitamin D in such non-bone health outcomes. Given the uncertainties surrounding the effects of vitamin D in non-bone health related outcomes, it was decided that this evaluation should focus on falls and the effects of vitamin D in bone health and exclusively within average-risk individuals and patients with kidney disease.
Synthesis of vitamin D occurs naturally in the skin through exposure to ultraviolet B (UVB) radiation from sunlight, but it can also be obtained from dietary sources including fortified foods, and supplements. Foods rich in vitamin D include fatty fish, egg yolks, fish liver oil, and some types of mushrooms. Since it is usually difficult to obtain sufficient vitamin D from non-fortified foods, either due to low content or infrequent use, most vitamin D is obtained from fortified foods, exposure to sunlight, and supplements.
Clinical Need: Condition and Target Population
Vitamin D deficiency may lead to rickets in infants and osteomalacia in adults. Factors believed to be associated with vitamin D deficiency include:
darker skin pigmentation,
winter season,
living at higher latitudes,
skin coverage,
kidney disease,
malabsorption syndromes such as Crohn’s disease, cystic fibrosis, and
genetic factors.
Patients with chronic kidney disease (CKD) are at a higher risk of vitamin D deficiency due to either renal losses or decreased synthesis of 1,25-dihydroxyvitamin D.
Health Canada currently recommends that, until the daily recommended intakes (DRI) for vitamin D are updated, Canada’s Food Guide (Eating Well with Canada’s Food Guide) should be followed with respect to vitamin D intake. Issued in 2007, the Guide recommends that Canadians consume two cups (500 ml) of fortified milk or fortified soy beverages daily in order to obtain a daily intake of 200 IU. In addition, men and women over the age of 50 should take 400 IU of vitamin D supplements daily. Additional recommendations were made for breastfed infants.
A Canadian survey evaluated the median vitamin D intake derived from diet alone (excluding supplements) among 35,000 Canadians, 10,900 of which were from Ontario. Among Ontarian males ages 9 and up, the median daily dietary vitamin D intake ranged between 196 IU and 272 IU per day. Among females, it varied from 152 IU to 196 IU per day. In boys and girls ages 1 to 3, the median daily dietary vitamin D intake was 248 IU, while among those 4 to 8 years it was 224 IU.
Vitamin D Testing
Two laboratory tests for vitamin D are available, 25-hydroxy vitamin D, referred to as 25(OH)D, and 1,25-dihydroxyvitamin D. Vitamin D status is assessed by measuring the serum 25(OH)D levels, which can be assayed using radioimmunoassays, competitive protein-binding assays (CPBA), high pressure liquid chromatography (HPLC), and liquid chromatography-tandem mass spectrometry (LC-MS/MS). These may yield different results with inter-assay variation reaching up to 25% (at lower serum levels) and intra-assay variation reaching 10%.
The optimal serum concentration of vitamin D has not been established and it may change across different stages of life. Similarly, there is currently no consensus on target serum vitamin D levels. There does, however, appear to be a consensus on the definition of vitamin D deficiency at 25(OH)D < 25 nmol/l, which is based on the risk of diseases such as rickets and osteomalacia. Higher target serum levels have also been proposed based on subclinical endpoints such as parathyroid hormone (PTH). Therefore, in this report, two conservative target serum levels have been adopted, 25 nmol/L (based on the risk of rickets and osteomalacia), and 40 to 50 nmol/L (based on vitamin D’s interaction with PTH).
Ontario Context
Volume & Cost
The volume of vitamin D tests done in Ontario has been increasing over the past 5 years with a steep increase of 169,000 tests in 2007 to more than 393,400 tests in 2008. The number of tests continues to rise with the projected number of tests for 2009 exceeding 731,000. According to the Ontario Schedule of Benefits, the billing cost of each test is $51.7 for 25(OH)D (L606, 100 LMS units, $0.517/unit) and $77.6 for 1,25-dihydroxyvitamin D (L605, 150 LMS units, $0.517/unit). Province wide, the total annual cost of vitamin D testing has increased from approximately $1.7M in 2004 to over $21.0M in 2008. The projected annual cost for 2009 is approximately $38.8M.
Evidence-Based Analysis
The objective of this report is to evaluate the clinical utility of vitamin D testing in the average risk population and in those with kidney disease. As a separate analysis, the report also sought to evaluate the prevalence of vitamin D deficiency in Canada. The specific research questions addressed were thus:
What is the clinical utility of vitamin D testing in the average risk population and in subjects with kidney disease?
What is the prevalence of vitamin D deficiency in the average risk population in Canada?
What is the prevalence of vitamin D deficiency in patients with kidney disease in Canada?
Clinical utility was defined as the ability to improve bone health outcomes with the focus on the average risk population (excluding those with osteoporosis) and patients with kidney disease.
Literature Search
A literature search was performed on July 17th, 2009 using OVID MEDLINE, MEDLINE In-Process and Other Non-Indexed Citations, EMBASE, the Cumulative Index to Nursing & Allied Health Literature (CINAHL), the Cochrane Library, and the International Agency for Health Technology Assessment (INAHTA) for studies published from January 1, 1998 until July 17th, 2009. Abstracts were reviewed by a single reviewer and, for those studies meeting the eligibility criteria, full-text articles were obtained. Reference lists were also examined for any additional relevant studies not identified through the search. Articles with unknown eligibility were reviewed with a second clinical epidemiologist, then a group of epidemiologists until consensus was established. The quality of evidence was assessed as high, moderate, low or very low according to GRADE methodology.
Observational studies that evaluated the prevalence of vitamin D deficiency in Canada in the population of interest were included based on the inclusion and exclusion criteria listed below. The baseline values were used in this report in the case of interventional studies that evaluated the effect of vitamin D intake on serum levels. Studies published in grey literature were included if no studies published in the peer-reviewed literature were identified for specific outcomes or subgroups.
Considering that vitamin D status may be affected by factors such as latitude, sun exposure, food fortification, among others, the search focused on prevalence studies published in Canada. In cases where no Canadian prevalence studies were identified, the decision was made to include studies from the United States, given the similar policies in vitamin D food fortification and recommended daily intake.
Inclusion Criteria
Studies published in English
Publications that reported the prevalence of vitamin D deficiency in Canada
Studies that included subjects from the general population or with kidney disease
Studies in children or adults
Studies published between January 1998 and July 17th 2009
Exclusion Criteria
Studies that included subjects defined according to a specific disease other than kidney disease
Letters, comments, and editorials
Studies that measured the serum vitamin D levels but did not report the percentage of subjects with serum levels below a given threshold
Outcomes of Interest
Prevalence of serum vitamin D less than 25 nmol/L
Prevalence of serum vitamin D less than 40 to 50 nmol/L
Serum 25-hydroxyvitamin D was the metabolite used to assess vitamin D status. Results from adult and children studies were reported separately. Subgroup analyses according to factors that affect serum vitamin D levels (e.g., seasonal effects, skin pigmentation, and vitamin D intake) were reported if enough information was provided in the studies
Quality of Evidence
The quality of the prevalence studies was based on the method of subject recruitment and sampling, possibility of selection bias, and generalizability to the source population. The overall quality of the trials was examined according to the GRADE Working Group criteria.
Summary of Findings
Fourteen prevalence studies examining Canadian adults and children met the eligibility criteria. With the exception of one longitudinal study, the studies had a cross-sectional design. Two studies were conducted among Canadian adults with renal disease but none studied Canadian children with renal disease (though three such US studies were included). No systematic reviews or health technology assessments that evaluated the prevalence of vitamin D deficiency in Canada were identified. Two studies were published in grey literature, consisting of a Canadian survey designed to measure serum vitamin D levels and a study in infants presented as an abstract at a conference. Also included were the results of vitamin D tests performed in community laboratories in Ontario between October 2008 and September 2009 (provided by the Ontario Association of Medical Laboratories).
Different threshold levels were used in the studies, thus we reported the percentage of subjects with serum levels of between 25 and 30 nmol/L and between 37.5 and 50 nmol/L. Some studies stratified the results according to factors affecting vitamin D status and two used multivariate models to investigate the effects of these characteristics (including age, season, BMI, vitamin D intake, skin pigmentation, and season) on serum 25(OH)D levels. It’s unclear, however, if these studies were adequately powered for these subgroup analyses.
Study participants generally consisted of healthy, community-dwelling subjects and most excluded individuals with conditions or medications that alter vitamin D or bone metabolism, such as kidney or liver disease. Although the studies were conducted in different parts of Canada, fewer were performed in Northern latitudes, i.e. above 53°N, which is equivalent to the city of Edmonton.
Adults
Serum vitamin D levels of < 25 to 30 nmol/L were observed in 0% to 25.5% of the subjects included in five studies; the weighted average was 3.8% (95% CI: 3.0, 4.6). The preliminary results of the Canadian survey showed that approximately 5% of the subjects had serum levels below 29.5 nmol/L. The results of over 600,000 vitamin D tests performed in Ontarian community laboratories between October 2008 and September 2009 showed that 2.6% of adults (> 18 years) had serum levels < 25 nmol/L.
The prevalence of serum vitamin D levels below 37.5-50 nmol/L reported among studies varied widely, ranging from 8% to 73.6% with a weighted average of 22.5%. The preliminary results of the CHMS survey showed that between 10% and 25% of subjects had serum levels below 37 to 48 nmol/L. The results of the vitamin D tests performed in community laboratories showed that 10% to 25% of the individuals had serum levels between 39 and 50 nmol/L.
In an attempt to explain this inter-study variation, the study results were stratified according to factors affecting serum vitamin D levels, as summarized below. These results should be interpreted with caution as none were adjusted for other potential confounders. Adequately powered multivariate analyses would be necessary to determine the contribution of risk factors to lower serum 25(OH)D levels.
Seasonal variation
Three adult studies evaluating serum vitamin D levels in different seasons observed a trend towards a higher prevalence of serum levels < 37.5 to 50 nmol/L during the winter and spring months, specifically 21% to 39%, compared to 8% to 14% in the summer. The weighted average was 23.6% over the winter/spring months and 9.6% over summer. The difference between the seasons was not statistically significant in one study and not reported in the other two studies.
Skin Pigmentation
Four studies observed a trend toward a higher prevalence of serum vitamin D levels < 37.5 to 50 nmol/L in subjects with darker skin pigmentation compared to those with lighter skin pigmentation, with weighted averages of 46.8% among adults with darker skin colour and 15.9% among those with fairer skin.
Vitamin D intake and serum levels
Four adult studies evaluated serum vitamin D levels according to vitamin D intake and showed an overall trend toward a lower prevalence of serum levels < 37.5 to 50 nmol/L with higher levels of vitamin D intake. One study observed a dose-response relationship between higher vitamin D intake from supplements, diet (milk), and sun exposure (results not adjusted for other variables). It was observed that subjects taking 50 to 400 IU or > 400 IU of vitamin D per day had a 6% and 3% prevalence of serum vitamin D level < 40 nmol/L, respectively, versus 29% in subjects not on vitamin D supplementation. Similarly, among subjects drinking one or two glasses of milk per day, the prevalence of serum vitamin D levels < 40 nmol/L was found to be 15%, versus 6% in those who drink more than two glasses of milk per day and 21% among those who do not drink milk. On the other hand, one study observed little variation in serum vitamin D levels during winter according to milk intake, with the proportion of subjects exhibiting vitamin D levels of < 40 nmol/L being 21% among those drinking 0-2 glasses per day, 26% among those drinking > 2 glasses, and 20% among non-milk drinkers.
The overall quality of evidence for the studies conducted among adults was deemed to be low, although it was considered moderate for the subgroups of skin pigmentation and seasonal variation.
Newborn, Children and Adolescents
Five Canadian studies evaluated serum vitamin D levels in newborns, children, and adolescents. In four of these, it was found that between 0 and 36% of children exhibited deficiency across age groups with a weighted average of 6.4%. The results of over 28,000 vitamin D tests performed in children 0 to 18 years old in Ontario laboratories (Oct. 2008 to Sept. 2009) showed that 4.4% had serum levels of < 25 nmol/L.
According to two studies, 32% of infants 24 to 30 months old and 35.3% of newborns had serum vitamin D levels of < 50 nmol/L. Two studies of children 2 to 16 years old reported that 24.5% and 34% had serum vitamin D levels below 37.5 to 40 nmol/L. In both studies, older children exhibited a higher prevalence than younger children, with weighted averages 34.4% and 10.3%, respectively. The overall weighted average of the prevalence of serum vitamin D levels < 37.5 to 50 nmol/L among pediatric studies was 25.8%. The preliminary results of the Canadian survey showed that between 10% and 25% of subjects between 6 and 11 years (N= 435) had serum levels below 50 nmol/L, while for those 12 to 19 years, 25% to 50% exhibited serum vitamin D levels below 50 nmol/L.
The effects of season, skin pigmentation, and vitamin D intake were not explored in Canadian pediatric studies. A Canadian surveillance study did, however, report 104 confirmed cases1 (2.9 cases per 100,000 children) of vitamin D-deficient rickets among Canadian children age 1 to 18 between 2002 and 2004, 57 (55%) of which from Ontario. The highest incidence occurred among children living in the North, i.e., the Yukon, Northwest Territories, and Nunavut. In 92 (89%) cases, skin pigmentation was categorized as intermediate to dark, 98 (94%) had been breastfed, and 25 (24%) were offspring of immigrants to Canada. There were no cases of rickets in children receiving ≥ 400 IU VD supplementation/day.
Overall, the quality of evidence of the studies of children was considered very low.
Kidney Disease
Adults
Two studies evaluated serum vitamin D levels in Canadian adults with kidney disease. The first included 128 patients with chronic kidney disease stages 3 to 5, 38% of which had serum vitamin D levels of < 37.5 nmol/L (measured between April and July). This is higher than what was reported in Canadian studies of the general population during the summer months (i.e. between 8% and 14%). In the second, which examined 419 subjects who had received a renal transplantation (mean time since transplantation: 7.2 ± 6.4 years), the prevalence of serum vitamin D levels < 40 nmol/L was 27.3%. The authors concluded that the prevalence observed in the study population was similar to what is expected in the general population.
Children
No studies evaluating serum vitamin D levels in Canadian pediatric patients with kidney disease could be identified, although three such US studies among children with chronic kidney disease stages 1 to 5 were. The mean age varied between 10.7 and 12.5 years in two studies but was not reported in the third. Across all three studies, the prevalence of serum vitamin D levels below the range of 37.5 to 50 nmol/L varied between 21% and 39%, which is not considerably different from what was observed in studies of healthy Canadian children (24% to 35%).
Overall, the quality of evidence in adults and children with kidney disease was considered very low.
Clinical Utility of Vitamin D Testing
A high quality comprehensive systematic review published in August 2007 evaluated the association between serum vitamin D levels and different bone health outcomes in different age groups. A total of 72 studies were included. The authors observed that there was a trend towards improvement in some bone health outcomes with higher serum vitamin D levels. Nevertheless, precise thresholds for improved bone health outcomes could not be defined across age groups. Further, no new studies on the association were identified during an updated systematic review on vitamin D published in July 2009.
With regards to non-bone health outcomes, there is no high or even moderate quality evidence that supports the effectiveness of vitamin D in outcomes such as cancer, cardiovascular outcomes, and all-cause mortality. Even if there is any residual uncertainty, there is no evidence that testing vitamin D levels encourages adherence to Health Canada’s guidelines for vitamin D intake. A normal serum vitamin D threshold required to prevent non-bone health related conditions cannot be resolved until a causal effect or correlation has been demonstrated between vitamin D levels and these conditions. This is as an ongoing research issue around which there is currently too much uncertainty to base any conclusions that would support routine vitamin D testing.
For patients with chronic kidney disease (CKD), there is again no high or moderate quality evidence supporting improved outcomes through the use of calcitriol or vitamin D analogs. In the absence of such data, the authors of the guidelines for CKD patients consider it best practice to maintain serum calcium and phosphate at normal levels, while supplementation with active vitamin D should be considered if serum PTH levels are elevated. As previously stated, the authors of guidelines for CKD patients believe that there is not enough evidence to support routine vitamin D [25(OH)D] testing. According to what is stated in the guidelines, decisions regarding the commencement or discontinuation of treatment with calcitriol or vitamin D analogs should be based on serum PTH, calcium, and phosphate levels.
Limitations associated with the evidence of vitamin D testing include ambiguities in the definition of an ‘adequate threshold level’ and both inter- and intra- assay variability. The MAS considers both the lack of a consensus on the target serum vitamin D levels and assay limitations directly affect and undermine the clinical utility of testing. The evidence supporting the clinical utility of vitamin D testing is thus considered to be of very low quality.
Daily vitamin D intake, either through diet or supplementation, should follow Health Canada’s recommendations for healthy individuals of different age groups. For those with medical conditions such as renal disease, liver disease, and malabsorption syndromes, and for those taking medications that may affect vitamin D absorption/metabolism, physician guidance should be followed with respect to both vitamin D testing and supplementation.
Conclusions
Studies indicate that vitamin D, alone or in combination with calcium, may decrease the risk of fractures and falls among older adults.
There is no high or moderate quality evidence to support the effectiveness of vitamin D in other outcomes such as cancer, cardiovascular outcomes, and all-cause mortality.
Studies suggest that the prevalence of vitamin D deficiency in Canadian adults and children is relatively low (approximately 5%), and between 10% and 25% have serum levels below 40 to 50 nmol/L (based on very low to low grade evidence).
Given the limitations associated with serum vitamin D measurement, ambiguities in the definition of a ‘target serum level’, and the availability of clear guidelines on vitamin D supplementation from Health Canada, vitamin D testing is not warranted for the average risk population.
Health Canada has issued recommendations regarding the adequate daily intake of vitamin D, but current studies suggest that the mean dietary intake is below these recommendations. Accordingly, Health Canada’s guidelines and recommendations should be promoted.
Based on a moderate level of evidence, individuals with darker skin pigmentation appear to have a higher risk of low serum vitamin D levels than those with lighter skin pigmentation and therefore may need to be specially targeted with respect to optimum vitamin D intake. The cause-effect of this association is currently unclear.
Individuals with medical conditions such as renal and liver disease, osteoporosis, and malabsorption syndromes, as well as those taking medications that may affect vitamin D absorption/metabolism, should follow their physician’s guidance concerning both vitamin D testing and supplementation.
PMCID: PMC3377517  PMID: 23074397
22.  The endocannabinoid system links gut microbiota to adipogenesis 
We investigated several models of gut microbiota modulation: selective (prebiotics, probiotics, high-fat), drastic (antibiotics, germ-free mice) and mice bearing specific mutations of a key gene involved in the toll-like receptors (TLR) bacteria-host interaction (Myd88−/−). Here we report that gut microbiota modulates the intestinal endocannabinoid (eCB) system-tone, which in turn regulates gut permeability and plasma lipopolysaccharide (LPS) levels.The activation of the intestinal endocannabinoid system increases gut permeability which in turn enhances plasma LPS levels and inflammation in physiological and pathological conditions such as obesity and type 2 diabetes.The investigation of adipocyte differentiation and lipogenesis (both markers of adipogenesis) indicate that gut microbiota controls adipose tissue physiology through LPS-eCB system regulatory loops and may play a critical role in the adipose tissue plasticity during obesity.In vivo, ex vivo and in vitro studies indicate that LPS acts as a master switch on adipose tissue metabolism, by blocking the cannabinoid-driven adipogenesis.
Obesity and type II diabetes have reached epidemic proportions and are associated with a massive expansion of the adipose tissue. Recent data have shown that these metabolic disorders are characterised by low-grade inflammation of unknown molecular origin (Hotamisligil and Erbay, 2008; Shoelson and Goldfine, 2009); therefore, it is of the utmost importance to identify the link between inflammation and adipose tissue metabolism and plasticity. Among the latest important discoveries published in the field, two new concepts have driven this study. First, emerging data have shown that gut microbiota is involved in the control of energy homeostasis (Ley et al, 2005; Turnbaugh et al, 2006; Claus et al, 2008) Obesity is characterised by the massive expansion of adipose tissues and is associated with inflammation (Weisberg et al, 2003). It is possible that both this expansion and the associated inflammation are controlled by microbiota and lipopolysaccharide (LPS) (Cani et al, 2007a, 2008), a cell wall component of Gram-negative bacteria that is among the most potent inducers of inflammation (Cani et al, 2007a, 2007b, 2008; Cani and Delzenne, 2009). Second, obesity is also characterised by greater endocannabinoid (eCB) system tone (increased eCB plasma levels, altered expression of the cannabinoid receptor 1 (CB1 mRNA) and increased eCB levels in the adipose tissue) (Engeli et al, 2005; Bluher et al, 2006; Matias et al, 2006; Cote et al, 2007; D'Eon et al, 2008; Starowicz et al, 2008; Di Marzo et al, 2009; Izzo et al, 2009).
Several studies have suggested a close relationship between LPS, gut microbiota and the eCB system. Indeed, LPS controls the synthesis of eCB in macrophages, whereas macrophage infiltration in the adipose tissue occurring during obesity is an important factor in the development of the metabolic disorders (Weisberg et al, 2003). We have shown that macrophage infiltration is not only dependent on the activation of the receptor CD14 by LPS, but is also dependent on the gut microbiota composition and the gut barrier function (gut permeability) (Cani et al, 2007a, 2008). Moreover, LPS controls the synthesis of eCBs both in vivo (Hoareau et al, 2009) and in vitro (Di Marzo et al, 1999; Maccarrone et al, 2001) through mechanisms dependent of the LPS receptor signalling pathway (Liu et al, 2003). Thus, obesity is nowadays associated with changes in gut microbiota and a higher endocannabinoid system tone, both having a function in the disease's pathophysiology.
Given that the convergent molecular mechanisms that may affect these different supersystem activities and adiposity remain to be elucidated, we tested the hypothesis that the gut microbiota and the eCB system control gut permeability and adipogenesis, by a LPS-dependent mechanism, under both physiological and obesity-related conditions.
First, we found that high-fat diet-induced obese and diabetic animals exhibit threefold higher colonic CB1 mRNA, whereas no modification was observed in the small intestinal segment (jejunum). Moreover, selective modulation of gut microbiota using prebiotics (i.e. non-digestible compounds fermented by specific bacteria in the gut) (Gibson and Roberfroid, 1995) reduces by about one half this effect. Similarly, in genetically obese mice (ob/ob), prebiotic treatment decreases colonic CB1 mRNA and colonic eCB concentrations (AEA) (Figure 2A). In addition, we have observed a modulation of FAAH and MGL mRNA (Figure 2A). Furthermore, we have found that antibiotic treatment decreasing the number of gut bacteria content was associated with a strong reduction of the CB1 receptor levels in the colon of healthy mice.
Second, we show that the endocannabinoid system controls gut barrier function (in vivo and in vitro) and endotoxaemia. More precisely, we designed two in vivo experiments in obese and lean mice (Figure 2). In a first experiment, we blocked the CB1 receptor in obese mice with a specific and selective antagonist (SR141716A) and found that the blockade of the CB1 receptor reduces plasma LPS levels by a mechanism linked to the improvement of the gut barrier function (Figure 2C) as shown by the lower alteration of tight junctions proteins (zonula occludens-1 (ZO-1) and occludin) distribution and localisation, and independently of food intake behaviour (Figures 2D and 3). In a second set of experiments performed in lean wild-type mice, we mimicked the increased eCB system tone observed during obesity by chronic (4-week) infusion of a cannabinoid receptor agonist (HU-210) through mini-pumps implanted subcutaneously. We found that cannabinoid agonist administration significantly increased plasma LPS levels. Furthermore, increased plasma fluorescein isothiocyanate-dextran levels were observed after oral gavage (Figure 2F and G). These sets of in vivo experiments strongly suggest that an overactive eCB system increases gut permeability. Finally, in a cellular model of intestinal epithelial barrier (Caco-2 cells monolayer), we found that CB1 receptor antagonist normalised LPS and the cannabinoid receptors agonist HU-210-induced epithelial barrier alterations.
Third, we provide evidence that adipogenesis is under the control of the gut microbiota, through the modulation of the gut and adipose tissue endocannabinoid systems in both physiological and pathological conditions. We found that the higher eCB system tone (found in obesity or mimicked by eCB agonist) participates to the regulation of adipogenesis by directly acting on the adipose tissue, but also indirectly by increasing plasma LPS levels, which consequently impair adipogenesis and promote inflammatory states. Here, we found that both the specific modulation of the gut microbiota and the blockade of the CB1 receptor decrease plasma LPS levels and is associated with higher adipocyte differentiation and lipogenesis rate. One possible explanation for these surprising data could be as follows: plasma LPS levels might be under the control of CB1 in the intestine (gut barrier function); therefore, under particular pathophysiological conditions in vivo (e.g. obesity/type II diabetes), this could lead to higher circulating LPS levels. Furthermore, CB1 receptor blockade might paradoxically increase adipogenesis because of the ability of CB1 antagonist to reduce gut permeability and counteract the LPS-induced inhibitory effect on adipocyte differentiation and lipogenesis (i.e. a disinhibition mechanism). In summary, given that these treatments reduce gut permeability and, hence, plasma LPS levels and inflammatory tone, we hypothesised that LPS could act as a regulator in this process. This hypothesis was further supported in vitro and in vivo by the observation that cannabinoid-induced adipocyte differentiation and lipogenesis were directly altered (i.e. reduced) in the presence of physiological levels of LPS. In summary, because these treatments reduce gut permeability, hence, plasma LPS and inflammatory tone, we hypothesised that LPS acts as a regulator in this process. Altogether, our data provide the evidence that the consequences of obesity and gut microbiota dysregulation on gut permeability and metabolic endotoxaemia are clearly mediated by the eCB system, those observed on adiposity are likely the result of two systems interactions: LPS-dependent pathways activities and eCB system tone dysregulation (Figure 9).
Our results indicate that the endocannabinoid system tone and the plasma LPS levels have a critical function in the regulation of the adipose tissue plasticity. As obesity is commonly characterised by increased eCB system tone, higher plasma LPS levels, altered gut microbiota and impaired adipose tissue metabolism, it is likely that the increased eCB system tone found in obesity is caused by a failure or a vicious cycle within the pathways controlling the eCB system.
These findings show that two novel therapeutic targets in the treatment of obesity, the gut microbiota and the endocannabinoid system, are closely interconnected. They also provide evidence for the presence of a new integrative physiological axis between gut and adipose tissue regulated by LPS and endocannabinoids. Finally, we propose that the increased endotoxaemia and endocannabinoid system tone found in obesity might explain the altered adipose tissue metabolism.
Obesity is characterised by altered gut microbiota, low-grade inflammation and increased endocannabinoid (eCB) system tone; however, a clear connection between gut microbiota and eCB signalling has yet to be confirmed. Here, we report that gut microbiota modulate the intestinal eCB system tone, which in turn regulates gut permeability and plasma lipopolysaccharide (LPS) levels. The impact of the increased plasma LPS levels and eCB system tone found in obesity on adipose tissue metabolism (e.g. differentiation and lipogenesis) remains unknown. By interfering with the eCB system using CB1 agonist and antagonist in lean and obese mouse models, we found that the eCB system controls gut permeability and adipogenesis. We also show that LPS acts as a master switch to control adipose tissue metabolism both in vivo and ex vivo by blocking cannabinoid-driven adipogenesis. These data indicate that gut microbiota determine adipose tissue physiology through LPS-eCB system regulatory loops and may have critical functions in adipose tissue plasticity during obesity.
doi:10.1038/msb.2010.46
PMCID: PMC2925525  PMID: 20664638
adipose tissue; endocannabinoids; gut microbiota; lipopolysaccharide (LPS); obesity
23.  Community-Based Care for the Specialized Management of Heart Failure 
Executive Summary
In August 2008, the Medical Advisory Secretariat (MAS) presented a vignette to the Ontario Health Technology Advisory Committee (OHTAC) on a proposed targeted health care delivery model for chronic care. The proposed model was defined as multidisciplinary, ambulatory, community-based care that bridged the gap between primary and tertiary care, and was intended for individuals with a chronic disease who were at risk of a hospital admission or emergency department visit. The goals of this care model were thought to include: the prevention of emergency department visits, a reduction in hospital admissions and re-admissions, facilitation of earlier hospital discharge, a reduction or delay in long-term care admissions, and an improvement in mortality and other disease-specific patient outcomes.
OHTAC approved the development of an evidence-based assessment to determine the effectiveness of specialized community based care for the management of heart failure, Type 2 diabetes and chronic wounds.
Please visit the Medical Advisory Secretariat Web site at: www.health.gov.on.ca/ohtas to review the following reports associated with the Specialized Multidisciplinary Community-Based care series.
Specialized multidisciplinary community-based care series: a summary of evidence-based analyses
Community-based care for the specialized management of heart failure: an evidence-based analysis
Community-based care for chronic wound management: an evidence-based analysis
Please note that the evidence-based analysis of specialized community-based care for the management of diabetes titled: “Community-based care for the management of type 2 diabetes: an evidence-based analysis” has been published as part of the Diabetes Strategy Evidence Platform at this URL: http://www.health.gov.on.ca/english/providers/program/mas/tech/ohtas/tech_diabetes_20091020.html
Please visit the Toronto Health Economics and Technology Assessment Collaborative Web site at: http://theta.utoronto.ca/papers/MAS_CHF_Clinics_Report.pdf to review the following economic project associated with this series:
Community-based Care for the specialized management of heart failure: a cost-effectiveness and budget impact analysis.
Objective
The objective of this evidence-based analysis was to determine the effectiveness of specialized multidisciplinary care in the management of heart failure (HF).
Clinical Need: Target Population and Condition
HF is a progressive, chronic condition in which the heart becomes unable to sufficiently pump blood throughout the body. There are several risk factors for developing the condition including hypertension, diabetes, obesity, previous myocardial infarction, and valvular heart disease.(1) Based on data from a 2005 study of the Canadian Community Health Survey (CCHS), the prevalence of congestive heart failure in Canada is approximately 1% of the population over the age of 12.(2) This figure rises sharply after the age of 45, with prevalence reports ranging from 2.2% to 12%.(3) Extrapolating this to the Ontario population, an estimated 98,000 residents in Ontario are believed to have HF.
Disease management programs are multidisciplinary approaches to care for chronic disease that coordinate comprehensive care strategies along the disease continuum and across healthcare delivery systems.(4) Evidence for the effectiveness of disease management programs for HF has been provided by seven systematic reviews completed between 2004 and 2007 (Table 1) with consistency of effect demonstrated across four main outcomes measures: all cause mortality and hospitalization, and heart-failure specific mortality and hospitalization. (4-10)
However, while disease management programs are multidisciplinary by definition, the published evidence lacks consistency and clarity as to the exact nature of each program and usual care comparators are generally ill defined. Consequently, the effectiveness of multidisciplinary care for the management of persons with HF is still uncertain. Therefore, MAS has completed a systematic review of specialized, multidisciplinary, community-based care disease management programs compared to a well-defined usual care group for persons with HF.
Evidence-Based Analysis Methods
Research Questions
What is the effectiveness of specialized, multidisciplinary, community-based care (SMCCC) compared with usual care for persons with HF?
Literature Search Strategy
A comprehensive literature search was completed of electronic databases including MEDLINE, MEDLINE In-Process and Other Non-Indexed Citations, EMBASE, Cochrane Library and Cumulative Index to Nursing & Allied Health Literature. Bibliographic references of selected studies were also searched. After a review of the title and abstracts, relevant studies were obtained and the full reports evaluated. All studies meeting explicit inclusion and exclusion criteria were retained. Where appropriate, a meta-analysis was undertaken to determine the pooled estimate of effect of specialized multidisciplinary community-based care for explicit outcomes. The quality of the body of evidence, defined as one or more relevant studies was determined using GRADE Working Group criteria. (11)
Inclusion Criteria
Randomized controlled trial
Systematic review with meta analysis
Population includes persons with New York Heart Association (NYHA) classification 1-IV HF
The intervention includes a team consisting of a nurse and physician one of which is a specialist in HF management.
The control group receives care by a single practitioner (e.g. primary care physician (PCP) or cardiologist)
The intervention begins after discharge from the hospital
The study reports 1-year outcomes
Exclusion Criteria
The intervention is delivered predominately through home-visits
Studies with mixed populations where discrete data for HF is not reported
Outcomes of Interest
All cause mortality
All cause hospitalization
HF specific mortality
HF specific hospitalization
All cause duration of hospital stay
HF specific duration of hospital stay
Emergency room visits
Quality of Life
Summary of Findings
One large and seven small randomized controlled trials were obtained from the literature search.
A meta-analysis was completed for four of the seven outcomes including:
All cause mortality
HF-specific mortality
All cause hospitalization
HF-specific hospitalization.
Where the pooled analysis was associated with significant heterogeneity, subgroup analyses were completed using two primary categories:
direct and indirect model of care; and
type of control group (PCP or cardiologist).
The direct model of care was a clinic-based multidisciplinary HF program and the indirect model of care was a physician supervised, nurse-led telephonic HF program.
All studies, except one, were completed in jurisdictions outside North America. (12-19) Similarly, all but one study had a sample size of less than 250. The mean age in the studies ranged from 65 to 77 years. Six of the studies(12;14-18) included populations with a NYHA classification of II-III. In two studies, the control treatment was a cardiologist (12;15) and two studies reported the inclusion of a dietitian, physiotherapist and psychologist as members of the multidisciplinary team (12;19).
All Cause Mortality
Eight studies reported all cause mortality (number of persons) at 1 year follow-up. (12-19) When the results of all eight studies were pooled, there was a statistically significant RRR of 29% with moderate heterogeneity (I2 of 38%). The results of the subgroup analyses indicated a significant RRR of 40% in all cause mortality when SMCCC is delivered through a direct team model (clinic) and a 35% RRR when SMCCC was compared with a primary care practitioner.
HF-Specific Mortality
Three studies reported HF-specific mortality (number of persons) at 1 year follow-up. (15;18;19) When the results of these were pooled, there was an insignificant RRR of 42% with high statistical heterogeneity (I2 of 60%). The GRADE quality of evidence is moderate for the pooled analysis of all studies.
All Cause Hospitalization
Seven studies reported all cause hospitalization at 1-year follow-up (13-15;17-19). When pooled, their results showed a statistically insignificant 12% increase in hospitalizations in the SMCCC group with high statistical heterogeneity (I2 of 81%). A significant RRR of 12% in all cause hospitalization in favour of the SMCCC care group was achieved when SMCCC was delivered using an indirect model (telephonic) with an associated (I2 of 0%). The Grade quality of evidence was found to be low for the pooled analysis of all studies and moderate for the subgroup analysis of the indirect team care model.
HF-Specific Hospitalization
Six studies reported HF-specific hospitalization at 1-year follow-up. (13-15;17;19) When pooled, the results of these studies showed an insignificant RRR of 14% with high statistical heterogeneity (I2 of 60%); however, the quality of evidence for the pooled analysis of was low.
Duration of Hospital Stay
Seven studies reported duration of hospital stay, four in terms of mean duration of stay in days (14;16;17;19) and three in terms of total hospital bed days (12;13;18). Most studies reported all cause duration of hospital stay while two also reported HF-specific duration of hospital stay. These data were not amenable to meta-analyses as standard deviations were not provided in the reports. However, in general (and in all but one study) it appears that persons receiving SMCCC had shorter hospital stays, whether measured as mean days in hospital or total hospital bed days.
Emergency Room Visits
Only one study reported emergency room visits. (14) This was presented as a composite of readmissions and ER visits, where the authors reported that 77% (59/76) of the SMCCC group and 84% (63/75) of the usual care group were either readmitted or had an ER visit within the 1 year of follow-up (P=0.029).
Quality of Life
Quality of life was reported in five studies using the Minnesota Living with HF Questionnaire (MLHFQ) (12-15;19) and in one study using the Nottingham Health Profile Questionnaire(16). The MLHFQ results are reported in our analysis. Two studies reported the mean score at 1 year follow-up, although did not provide the standard deviation of the mean in their report. One study reported the median and range scores at 1 year follow-up in each group. Two studies reported the change scores of the physical and emotional subscales of the MLHFQ of which only one study reported a statistically significant change from baseline to 1 year follow-up between treatment groups in favour of the SMCCC group in the physical sub-scale. A significant change in the emotional subscale scores from baseline to 1 year follow-up in the treatment groups was not reported in either study.
Conclusion
There is moderate quality evidence that SMCCC reduces all cause mortality by 29%. There is low quality evidence that SMCCC contributes to a shorter duration of hospital stay and improves quality of life compared to usual care. The evidence supports that SMCCC is effective when compared to usual care provided by either a primary care practitioner or a cardiologist. It does not, however, suggest an optimal model of care or discern what the effective program components are. A field evaluation could address this uncertainty.
PMCID: PMC3377506  PMID: 23074521
24.  Features of primary care associated with variations in process and outcome of care of people with diabetes. 
BACKGROUND: There is now clear evidence that tight control of blood glucose and blood pressure significantly lowers the risk of complications in both type I and type II diabetes. Although there is evidence that primary care can be as effective as secondary care in delivering care for people with diabetes, standards in primary care are variable. Previous studies have shown that practice, patient or organisational factors may influence the level of care of patients with diabetes. However, these studies have been conducted in single geographical areas and involved only small numbers of practices. AIM: To determine the standard of diabetes care in general practice and to determine which features of practices are associated with delivering good quality care. DESIGN OF STUDY: A questionnaire survey and analysis of multi-practice audit data. SETTING: Three health authorities in England, comprising 169 general practices. METHOD: This study was conducted with a total population of 1,182,872 patients and 18,642 people with diabetes. Linkage analysis was carried out on data collected by a questionnaire, routinely collected health authority data, and multi-practice audit data collected by primary care audit groups. Practice annual compliance was measured with process and outcome measures of care, including the proportion of patients who had an examination of their fundi, feet, blood pressure, urine, glycated haemoglobin, and the proportion who had a normal glycated haemoglobin. RESULTS: Median compliance with process and outcome measures of care varied widely between practices: fundi were checked for 64.6% of patients (interquartile range [IQR] = 45.3-77.8%), urine was checked for 71.4% (IQR = 49.7-84.3%), feet were checked for 70.4% (IQR = 51.0-84.4%), blood pressure for 83.6% (IQR = 66.7-91.5%), and glycated haemoglobin was checked for 83.0% of patients (IQR = 69.4-92.0%). The glycated haemoglobin was normal in 42.9% of patients (IQR = 33.0-51.2%). In multiple regression analysis, compliance with measures of process of care were significantly associated with smaller practices, fundholding practices, and practices with a recall system. Practices with more socioeconomically deprived patients were associated with lower compliance with most process measures. Practices with a greater proportion of patients attending hospital clinics had lower compliance with process and outcome measures. Being a training practice, having a diabetes mini-clinic, having more nurses, personal care, and general practitioner or nurse interest in diabetes were not associated with compliance of process or outcome of care. CONCLUSIONS: Despite recent evidence that complications of diabetes may be delayed or prevented, this study has highlighted a number of deficiencies in the provision of diabetes care and variations in care between general practices. Provision of high quality diabetes care in the United Kingdom will present an organisational challenge to primary care groups and trusts, especially those in deprived areas.
PMCID: PMC1313998  PMID: 11360698
25.  Rotating Night Shift Work and Risk of Type 2 Diabetes: Two Prospective Cohort Studies in Women 
PLoS Medicine  2011;8(12):e1001141.
An Pan and colleagues examined data from two Nurses' Health Studies and found that extended periods of rotating night shift work were associated with a modestly increased risk of type 2 diabetes, partly mediated through body weight.
Background
Rotating night shift work disrupts circadian rhythms and has been associated with obesity, metabolic syndrome, and glucose dysregulation. However, its association with type 2 diabetes remains unclear. Therefore, we aimed to evaluate this association in two cohorts of US women.
Methods and Findings
We followed 69,269 women aged 42–67 in Nurses' Health Study I (NHS I, 1988–2008), and 107,915 women aged 25–42 in NHS II (1989–2007) without diabetes, cardiovascular disease, and cancer at baseline. Participants were asked how long they had worked rotating night shifts (defined as at least three nights/month in addition to days and evenings in that month) at baseline. This information was updated every 2–4 years in NHS II. Self-reported type 2 diabetes was confirmed by a validated supplementary questionnaire. We documented 6,165 (NHS I) and 3,961 (NHS II) incident type 2 diabetes cases during the 18–20 years of follow-up. In the Cox proportional models adjusted for diabetes risk factors, duration of shift work was monotonically associated with an increased risk of type 2 diabetes in both cohorts. Compared with women who reported no shift work, the pooled hazard ratios (95% confidence intervals) for participants with 1–2, 3–9, 10–19, and ≥20 years of shift work were 1.05 (1.00–1.11), 1.20 (1.14–1.26), 1.40 (1.30–1.51), and 1.58 (1.43–1.74, p-value for trend <0.001), respectively. Further adjustment for updated body mass index attenuated the association, and the pooled hazard ratios were 1.03 (0.98–1.08), 1.06 (1.01–1.11), 1.10 (1.02–1.18), and 1.24 (1.13–1.37, p-value for trend <0.001).
Conclusions
Our results suggest that an extended period of rotating night shift work is associated with a modestly increased risk of type 2 diabetes in women, which appears to be partly mediated through body weight. Proper screening and intervention strategies in rotating night shift workers are needed for prevention of diabetes.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Around 346 million people worldwide have diabetes—a chronic disease affecting blood glucose levels, which over time may lead to serious damage in many body systems. In 2004, an estimated 3.4 million people died from consequences of high blood sugar, with more than 80% of deaths occurring in low-and middle-income countries. Type 2 diabetes accounts for 90% of people with diabetes and is largely the result of excess body weight and physical inactivity, which causes the body to use insulin ineffectively. One strategy in the public health response to the increasing prevalence and incidence of type 2 diabetes is to focus on the prevention and management of obesity by targeting risk factors of obesity.
Previous studies have suggested that rotating night shift work, which is common and becoming increasingly prevalent in countries worldwide, is associated with an increased risk of obesity and metabolic syndrome, conditions closely related to type 2 diabetes.
Why Was This Study Done?
Some studies have investigated the association between rotating night shift work and type 2 diabetes but have experienced methodological problems (such as minimal information on the rotating shift work, small sample sizes, and limited study populations), which make interpretation of the results difficult. In this study, the researchers attempted to overcome these methodological issues by prospectively examining the relationship between duration of rotating night shift work and risk of incident type 2 diabetes and, also if the duration of shift work was associated with greater weight gain, in two large cohorts of women in the United States.
What Did the Researchers Do and Find?
The researchers used data from the Nurses' Health Study I (NHS I, established in 1976 and included 121,704 women) and the Nurses' Health Study II (NHS II, established in 1989 and included 116,677 women), in which participating women completed regular questionnaires about their lifestyle practices and the development of chronic diseases. In both studies, the women also gave information about how long they had done rotating night shifts work (defined as at least three nights/month in addition to 19 days and evenings in that month), and this information was updated at regular intervals over the study follow-up period (18 years). The comparison group was women who did not report a history of rotating night shift work.
To assess the incidence of diabetes in both cohorts, the researchers sent a supplementary questionnaire to women who reported a diagnosis of diabetes, which asked about the symptoms, diagnostic tests, and medical management: if at least one of the National Diabetes Data Group criteria was reported, the researchers considered confirmed a diagnosis of type 2 diabetes. The researchers then used statistical methods (time-dependent Cox proportional hazards models) to estimate the hazard ratios of the chance of women working rotating shifts developing type 2 diabetes as a ratio of the chance of women not working rotating shifts developing diabetes.
The researchers found that in NHS I, 6,165 women developed type 2 diabetes and in NHS II 3,961 women developed type 2 diabetes. Using their statistical models, the researchers found that the duration of rotating night shift work was strongly associated with an increased risk of type 2 diabetes in both cohorts. The researchers found that in both cohorts, compared with women who reported no rotating night shift work, the HR of women developing type 2 diabetes, increased with the numbers of years working rotating shifts (the HRs of working rotating shifts for 1–2, 3–9, 10–19, and ≥20 years were 0.99, 1.17, 1.42, and 1.64, respectively, in NHS I, and in NHS II, 1.13, 1.34, 1.76, and 2.50, respectively). However, these associations were slightly weaker after the authors took other factors into consideration, except for body mass index (BMI).
What Do These Findings Mean?
These findings show that in these women, there is a positive association between rotating night shift work and the risk of developing type 2 diabetes. Furthermore, long duration of shift work may also be associated with greater weight gain. Although these findings need to be confirmed in men and other ethnic groups, because a large proportion of the working population is involved in some kind of permanent night and rotating night shift work, these findings are of potential public health significance. Additional preventative strategies in rotating night shift workers should therefore be considered.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001141.
This study is further discussed in a PLoS Medicine Perspective by Mika Kivimki and colleagues
Wikipedia has information about the Nurses’ Health study (note that Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)
Detailed information about the Nurses’ Health Study is available
The World Health Organization provides comprehensive information about all kinds of diabetes
For more information about diabetes that is useful for patients see Diabetes UK
doi:10.1371/journal.pmed.1001141
PMCID: PMC3232220  PMID: 22162955

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