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Purpose

This study sought to determine whether abdominal obesity is a risk factor for impaired fasting glucose (IFG) and hypertriglyceridemia and to verify whether moderate effect of abdominal obesity on the relationship between IFG and hypertriglyceridemia in Korea.

Materials and Methods

Data from the Korean National Health and Nutrition Examination Survey was used for the analysis. The study population included 5,938 subjects aged 20 year old drawn from non-diabetic participants in a health examination survey. The subjects were classified according to the presence of abdominal obesity based on waist circumference, IFG based on their fasting blood glucose level, and hypertriglyceridemia on their fasting triglyceride.

Results

The multivariate-adjusted odds ratios for the occurrence of hypertriglyceridemia were 2.91 in the abdominal obesity group as compared with the nonobesity group and 1.31 in subjects with IFG compared with the normoglycemia controls. Abdominal obesity was found to be positively moderated in the interaction between waist circumference and fasting blood sugar.

Conclusion

The moderate effect between abdominal obesity and IFG contributes to the development of hypertriglyceridemia in Korea.

Background:

Elevated triglycerides (TGs) are a common lipid disorder in the US and are associated with comorbidities such as pancreatitis, obesity, type 2 diabetes, and metabolic syndrome. TGs are generally elevated in postmenopausal women compared with premenopausal women. Meta-analysis has shown that elevated TGs are associated with an increased risk of coronary heart disease (CHD).

Objective:

This article provides a general overview of TG metabolism and reviews data on the epidemiology and risk of elevated TGs in women, as pregnancy and menopause, in particular, have been associated with unfavorable changes in the lipoprotein profile, including elevations in TGs. In addition, this review seeks to explain the recommended TG goals and treatment options for hypertriglyceridemia with an emphasis on severe hypertriglyceridemia (TGs ≥ 500 mg/dL) and its respective treatment with prescription omega-3-acid ethyl esters (P-OM3).

Methods:

MedLine was searched for articles published through August 2009 using the terms “hypertriglyceridemia” and “dyslipidemia”, with subheadings for “prevalence”, “women”, “treatment”, “guidelines”, “risk”, and “omega-3 fatty acids”. Publications discussing the epidemiology of hypertriglyceridemia, CHD risk, treatment guidelines for lipid management, or clinical trials involving P-OM3 were selected for review. The reference lists of relevant articles were also examined for additional citations.

Results:

Hypertriglyceridemia is associated with increased CHD risk. Women, especially those with polycystic ovarian syndrome, type 2 diabetes, or who are postmenopausal, should be monitored regularly for the impact of hypertriglyceridemia on their lipid profile. Cardiovascular risk of TGs can be indirectly assessed by monitoring non-high-density lipoprotein cholesterol (non-HDL-C) levels. There are multiple sets of guidelines providing recommendations for desirable low-density lipoprotein cholesterol, TG, and non-HDL-C levels. Treatment of hypertriglyceridemia includes lifestyle interventions and, if needed, pharmacologic therapy. In patients with severe hypertriglyceridemia, P-OM3 can reduce TGs by up to 45%.

Conclusion:

Physicians should regularly monitor the lipid profile of their female patients. Any lipid abnormality should be managed promptly according to established guidelines. P-OM3 provide a well-tolerated option for the treatment of severe hypertriglyceridemia.

Hypertriglyceridemia is a prevalent risk factor for cardiovascular disease (CVD) and increasingly important in the setting of current obesity and insulin resistance epidemics. High triglyceride (TG) levels are markers for several types of atherogenic lipoproteins. Patients who have hypertriglyceridemia may be at significant risk for CVD even if low-density lipoprotein cholesterol levels are at goal, and therefore warrant treatment that optimizes diet, reduces overweight, and promotes regular exercise. High-risk patients with hypertriglyceridemia, such as those with diabetes, CVD, or metabolic syndrome, may benefit from additional drug treatment aside from a statin to address other lipid abnormalities. In this discussion, we review the role of hypertriglyceridemia and its associated atherogenic lipoproteins in the pathogenesis of atherosclerosis, the relevance of a high TG level as a predictor of CVD, the cardiovascular outcomes from TG-lowering intervention trials, and the current guidelines for treating hypertriglyceridemia.

In order to describe the prevalence of hypercholesterolemia and hypertriglyceridemia in a cohort of HIV-infected children and adolescents in Latin America and to determine associations with highly active antiretroviral therapy (HAART), we performed this cross-sectional analysis within the NICHD International Site Development Initiative pediatric cohort study. Eligible children had to be at least 2 years of age and be on HAART. Among the 477 eligible HIV-infected youth, 98 (20.5%) had hypercholesterolemia and 140 (29.4%) had hypertriglyceridemia. In multivariable analyses, children receiving protease inhibitor (PI)-containing HAART were at increased risk for hypercholesterolemia [adjusted odds ratio (AOR) = 2.7, 95% confidence interval (CI) 1.3–5.6] and hypertriglyceridemia (AOR = 3.5, 95% CI 1.9–6.4) compared with children receiving non-nucleoside reverse transcriptase inhibitor (NNRTI)-containing HAART. In conclusion, HIV-infected youth receiving PI-containing HAART in this Latin American cohort were at increased risk for hypercholesterolemia and hypertriglyceridemia compared with those receiving NNRTI-containing HAART.

Chylomicronemia syndrome is a rare disorder characterized by the presence of chylomicrons in the fasting state. An acute and potentially life-threatening complication of chyiomicronemia syndrome is severe acute pancreatitis. We report a case of a 24-year-old primigravida with severe hypertriglyceridemia-induced pancreatitis. We reviewed the clinical course and treatment of hypertriglyceridemia-induced pancreatitis. She was admitted in the 37th week of gestation with severe abdominal pain, which was radiating to the back, and having uterine contractions. Cesarean delivery was performed under spinal anesthesia, and a healthy male infant was born. Intraoperative findings included milky peritoneal fluid collection. Elevated pancreatic enzymes with significant hypertriglyceridemia (10,092 mg/dL) suggesting acute pancreatitis were also found on chemical analysis. The diagnosis of acute pancreatitis was confirmed by computed tomography scan. Treatment with continuous intravenous insulin--glucose, cessation of oral intake, and nasogastric decompression--dramatically decreased the triglyceride levels to 608 mg/dL within five days. She was discharged as symptom free with strict dietary intervention after 10 days. Intravenous insulin is a low-cost and effective alternative treatment in hypertriglyceridemia-induced pancreatitis during pregnancy. To our knowledge, such a high triglyceride level has not previously been reported in pregnancy.

Objective To systematically review interventional studies of the effects of alcohol consumption on 21 biological markers associated with risk of coronary heart disease in adults without known cardiovascular disease.

Design Systematic review and meta-analysis.

Data sources Medline (1950 to October 2009) and Embase (1980 to October 2009) without limits.

Study selection Two reviewers independently selected studies that examined adults without known cardiovascular disease and that compared fasting levels of specific biological markers associated with coronary heart disease after alcohol use with those after a period of no alcohol use (controls). 4690 articles were screened for eligibility, the full texts of 124 studies reviewed, and 63 relevant articles selected.

Results Of 63 eligible studies, 44 on 13 biomarkers were meta-analysed in fixed or random effects models. Quality was assessed by sensitivity analysis of studies grouped by design. Analyses were stratified by type of beverage (wine, beer, spirits). Alcohol significantly increased levels of high density lipoprotein cholesterol (pooled mean difference 0.094 mmol/L, 95% confidence interval 0.064 to 0.123), apolipoprotein A1 (0.101 g/L, 0.073 to 0.129), and adiponectin (0.56 mg/L, 0.39 to 0.72). Alcohol showed a dose-response relation with high density lipoprotein cholesterol (test for trend P=0.013). Alcohol decreased fibrinogen levels (−0.20 g/L, −0.29 to −0.11) but did not affect triglyceride levels. Results were similar for crossover and before and after studies, and across beverage types.

Conclusions Favourable changes in several cardiovascular biomarkers (higher levels of high density lipoprotein cholesterol and adiponectin and lower levels of fibrinogen) provide indirect pathophysiological support for a protective effect of moderate alcohol use on coronary heart disease.

Objectives: To examine whether the increased risk of cardiovascular events with rofecoxib represents a class effect of cyclooxygenase-2 (COX-2) specific inhibitors.

Design: Systematic review and meta-analysis of randomized double-blind clinical trials of celecoxib of at least 6 weeks' duration and presented data on serious cardiovascular thromboembolic events. Data sources included six bibliographic databases, the relevant files of the United States Food and Drug Administration, and pharmaceutical company websites.

Main outcome measures: Pooled fixed effects estimates of the odds ratios for risk of cardiovascular events with celecoxib compared with comparator treatment were calculated using the inverse variance weight method. The main outcome measure was myocardial infarction.

Results: Four placebo-controlled trials with 4422 patients were included in the primary meta-analysis comparing celecoxib with placebo. The odds ratio of myocardial infarction with celecoxib compared to placebo was 2.26 (95%confidence interval 1.0 to 5.1). For composite cardiovascular events [odd ratio 1.38 (95% CI 0.91 to 2.10)], cardiovascular deaths [OR 1.06 (95% CI 0.38 to 2.95)] and stroke [OR 1.0(95% CI 0.51 to 1.84)] there was no significant increase in risk with celecoxib. The secondary meta-analysis which included a total of six studies (with placebo, diclofenac, ibuprofen, and paracetamol as comparators) of 12 780 patients, showed similar findings with a significant increased risk with celecoxib for myocardial infarction [OR 1.88 (95% CI 1.15 to 3.08)] but not other outcome measures.

Conclusion: The available data indicate an increased risk of myocardial infarction with celecoxib therapy, consistent with a class effect for COX-2 specific inhibitors.

Objective To conduct a comprehensive systematic review and meta-analysis of studies assessing the effect of alcohol consumption on multiple cardiovascular outcomes.

Design Systematic review and meta-analysis.

Data sources A search of Medline (1950 through September 2009) and Embase (1980 through September 2009) supplemented by manual searches of bibliographies and conference proceedings.

Inclusion criteria Prospective cohort studies on the association between alcohol consumption and overall mortality from cardiovascular disease, incidence of and mortality from coronary heart disease, and incidence of and mortality from stroke.

Studies reviewed Of 4235 studies reviewed for eligibility, quality, and data extraction, 84 were included in the final analysis.

Results The pooled adjusted relative risks for alcohol drinkers relative to non-drinkers in random effects models for the outcomes of interest were 0.75 (95% confidence interval 0.70 to 0.80) for cardiovascular disease mortality (21 studies), 0.71 (0.66 to 0.77) for incident coronary heart disease (29 studies), 0.75 (0.68 to 0.81) for coronary heart disease mortality (31 studies), 0.98 (0.91 to 1.06) for incident stroke (17 studies), and 1.06 (0.91 to 1.23) for stroke mortality (10 studies). Dose-response analysis revealed that the lowest risk of coronary heart disease mortality occurred with 1–2 drinks a day, but for stroke mortality it occurred with ≤1 drink per day. Secondary analysis of mortality from all causes showed lower risk for drinkers compared with non-drinkers (relative risk 0.87 (0.83 to 0.92)).

Conclusions Light to moderate alcohol consumption is associated with a reduced risk of multiple cardiovascular outcomes.

Objectives

To correlate cardiovascular risk factors (e.g., hypertension, obesity, hypercholesterolemia, hypertriglyceridemia, hyperglycemia, sedentariness) in childhood and adolescence with the occurrence of cardiovascular disease.

Sources

A systematic review of books and selected articles from PubMed, SciELO and Cochrane from 1992 to 2012.

Summary of findings

Risk factors for atherosclerosis are present in childhood, although cardiovascular disease arises during adulthood. This article presents the main studies that describe the importance of investigating the risk factors for cardiovascular diseases in childhood and their associations. Significant rates of hypertension, obesity, dyslipidemia, and sedentariness occur in children and adolescents. Blood pressure needs to be measured in childhood. An increase in arterial blood pressure in young people predicts hypertension in adulthood. The death rate from cardiovascular disease is lowest in children with lower cholesterol levels and in individuals who exercise regularly. In addition, there is a high prevalence of sedentariness in children and adolescents.

Conclusions

Studies involving the analysis of cardiovascular risk factors should always report the prevalence of these factors and their correlations during childhood because these factors are indispensable for identifying an at-risk population. The identification of risk factors in asymptomatic children could contribute to a decrease in cardiovascular disease, preventing such diseases as hypertension, obesity, and dyslipidemia from becoming the epidemics of this century.

Objective

To assess the long term effects of advice to restrict dietary sodium in adults with and without hypertension.

Design

Systematic review and meta-analysis of randomised controlled trials.

Data sources

Cochrane library, Medline, Embase, and bibliographies.

Study selection

Unconfounded randomised trials that aimed to reduce sodium intake in healthy adults over at least 6 months. Inclusion decisions, validity and data extraction were duplicated. Random effects meta-analysis, subgrouping, sensitivity analysis, and meta-regression were performed.

Outcomes

Mortality, cardiovascular events, blood pressure, urinary sodium excretion, quality of life, and use of antihypertensive drugs.

Results

Three trials in normotensive people (n=2326), five trials in those with untreated hypertension (n=387), and three trials in people being treated for hypertension (n=801) were included, with follow up from six months to seven years. The large high quality (and therefore most informative) studies used intensive behavioural interventions. Deaths and cardiovascular events were inconsistently defined and reported. There were 17 deaths, equally distributed between intervention and control groups. Systolic and diastolic blood pressures were reduced (systolic by 1.1 mm Hg, 95% confidence interval 1.8 to 0.4 mm Hg; diastolic by 0.6 mm Hg, 1.5 to −0.3 mm Hg) at 13 to 60 months, as was urinary 24 hour sodium excretion (by 35.5 mmol/24 hours, 47.2 to 23.9). Degree of reduction in sodium intake and change in blood pressure were not related.

Conclusions

Intensive interventions, unsuited to primary care or population prevention programmes, provide only small reductions in blood pressure and sodium excretion, and effects on deaths and cardiovascular events are unclear. Advice to reduce sodium intake may help people on antihypertensive drugs to stop their medication while maintaining good blood pressure control.

What is already known on this topicRestricting sodium intake in people with hypertension reduces blood pressureLong term effects (on blood pressure, mortality, and morbidity) of reduced salt intake in people with and without hypertension are unclearWhat this study addsFew deaths and cardiovascular events have been reported in salt reduction trialsMeta-analysis shows that blood pressure was reduced (systolic by 1.1 mm Hg, diastolic by 0.6 mm Hg) at 13 to 60 months, with a reduction in sodium excretion of almost a quarter (35.5 mmol/24 hours)The interventions used were highly intensive and unsuited to primary care or population prevention programmesLower salt intake may help people on antihypertensive drugs to stop their medication while maintaining good control of blood pressure, but there are doubts about effects of sodium reduction on overall health

Background

Aspirin has been recommended for the prevention of major adverse cardiovascular events (MACE, composite of non-fatal myocardial infarction, non-fatal stroke, and cardiovascular death) in diabetic patients without previous cardiovascular disease. However, recent meta-analyses have prompted re-evaluation of this practice. The study objective was to evaluate the relative and absolute benefits and harms of aspirin for the prevention of incident MACE in patients with diabetes.

Methods

We performed a systematic review and meta-analysis on seven studies (N = 11,618) reporting on the use of aspirin for the primary prevention of MACE in patients with diabetes. Two reviewers conducted a systematic search of electronic databases (MEDLINE, EMBASE, the Cochrane Library, and BIOSIS) and hand searched bibliographies and clinical trial registries. Reviewers extracted data in duplicate, evaluated the quality of the trials, and calculated pooled estimates.

Results

A total of 11,618 participants were included in the analysis. The overall risk ratio (RR) for MACE was 0.91 (95% confidence intervals, CI, 0.82-1.00) with little heterogeneity among trials (I2 0.0%). Secondary outcomes of interest included myocardial infarction (RR, 0.85; 95% CI, 0.66-1.10), stroke (RR, 0.84; 95% CI, 0.64-1.11), cardiovascular death (RR, 0.95; 95% CI, 0.71-1.27), and all-cause mortality (RR, 0.95; 95% CI, 0.85-1.06). There were higher rates of hemorrhagic and gastrointestinal events. In absolute terms, these relative risks indicate that for every 10,000 diabetic patients treated with aspirin, 109 MACE may be prevented at the expense of 19 major bleeding events (with the caveat that the relative risk for the latter is not statistically significant).

Conclusions

The studies reviewed suggest that aspirin reduces the risk of MACE in patients with diabetes without cardiovascular disease, while also causing a trend toward higher rates of bleeding and gastrointestinal complications. These findings and our absolute benefit and risk calculations suggest that those with diabetes but without cardiovascular disease lie somewhere between primary and secondary prevention patients on the spectrum of benefit and risk. This underscores the importance of considering individual risk in clinical decision making regarding aspirin in those with diabetes.

Objective To evaluate the accumulated information from genetic association studies investigating the impact of variants of the cytochrome P450 (CYP) 2C19 genotype on the clinical efficacy of clopidogrel.

Design Systematic review and meta-analysis with a structured search algorithm and prespecified eligibility criteria for retrieval of relevant studies; dominant genetic model assumptions and quantitative methods for calculating summary effect estimates from study level odds ratios; systematic assessment of bias within and between studies; and grading of the cumulative evidence by consensus criteria.

Data sources Medline, Embase, the Cochrane Library, online databases, contents pages and bibliographies of general medical, cardiovascular, pharmacological, and genetic journals.

Eligibility criteria for selecting studies Original full length reports assessing the cumulative incidence of major adverse cardiovascular events or stent thrombosis over a follow-up period of at least a month in association with carrier status for the loss of function or gain of function CYP2C19 allele in adult patients with coronary artery disease and a clinical presentation of acute coronary syndrome or stable angina pectoris who were taking clopidogrel.

Results 15 studies met the inclusion criteria. The random effects summary odds ratio for stent thrombosis in carriers of at least one CYP2C19 loss of function allele versus non-carriers combining nine studies was 1.77 (95% confidence interval 1.31 to 2.40; P<0.001). This nominally significant odds ratio was subject to considerable bias across the studies (small study effect bias and replication diversity). The adjustment for these quality modifiers tended to abolish the association. The corresponding random effects summary odds ratio of major adverse cardiovascular events for 12 studies combined was 1.11 (0.89 to 1.39; P=0.36). The random effects summary odds ratio of stent thrombosis in carriers versus non-carriers of at least one CYP2C19*17 gain of function allele for three studies combined was 0.99 (0.60 to 1.62; P=0.96), and the corresponding odds ratio of major adverse cardiovascular events in five studies was 0.93 (0.75 to 1.14; P=0.48). The overall quality of epidemiological evidence was graded as low, which excludes reliable clinical assessments.

Conclusions Accumulated information from genetic association studies does not indicate a substantial or consistent influence of CYP2C19 gene polymorphisms on the clinical efficacy of clopidogrel. The current evidence does not support the use of individualised antiplatelet regimens guided by CYP2C19 genotype.

Purpose of review

This review focuses on studies from the past year that highlight molecular and cellular mechanisms of pancreatic injury arising from acute and chronic pancreatitis.

Recent findings

Factors that induce or ameliorate injury as well as cellular pathways involved have been examined. Causative or sensitizing factors include refluxed bile acids, hypercalcemia, ethanol, hypertriglyceridemia, and acidosis. In addition, the diabetes drug exendin-4 has been associated with pancreatitis, whereas other drugs may reduce pancreatic injury. The intracellular events that influence disease severity are better understood. Cathepsin-L promotes injury through an antiapoptotic effect, rather than by trypsinogen activation. In addition, specific trypsinogen mutations lead to trypsinogen misfolding, endoplasmic reticulum stress, and injury. Endogenous trypsin inhibitors and upregulation of proteins including Bcl-2, fibroblast growth factor 21, and activated protein C can reduce injury. Immune cells, however, have been shown to increase injury via an antiapoptotic effect.

Summary

The current findings are critical to understanding how causative factors initiate downstream cellular events resulting in pancreatic injury. Such knowledge will aid in the development of targeted treatments for pancreatitis. This review will first discuss factors influencing pancreatic injury, and then conclude with studies detailing the cellular mechanisms involved.

Background:

There have been postmarketing reports of adverse cardiovascular events associated with the use of varenicline, a widely used smoking cessation drug. We conducted a systematic review and meta-analysis of randomized controlled trials to ascertain the serious adverse cardiovascular effects of varenicline compared with placebo among tobacco users.

Methods:

We searched MEDLINE, EMBASE, the Cochrane Database of Systematic Reviews, websites of regulatory authorities and registries of clinical trials, with no date or language restrictions, through September 2010 (updated March 2011) for published and unpublished studies. We selected double-blind randomized controlled trials of at least one week’s duration involving smokers or people who used smokeless tobacco that reported on cardiovascular events (ischemia, arrhythmia, congestive heart failure, sudden death or cardiovascular-related death) as serious adverse events asociated with the use of varenicline.

Results:

We analyzed data from 14 double-blind randomized controlled trials involving 8216 participants. The trials ranged in duration from 7 to 52 weeks. Varenicline was associated with a significantly increased risk of serious adverse cardiovascular events compared with placebo (1.06% [52/4908] in varenicline group v. 0.82% [27/3308] in placebo group; Peto odds ratio [OR] 1.72, 95% confidence interval [CI] 1.09–2.71; I2 = 0%). The results of various sensitivity analyses were consistent with those of the main analysis, and a funnel plot showed no publication bias. There were too few deaths to allow meaningful comparisons of mortality.

Interpretation:

Our meta-analysis raises safety concerns about the potential for an increased risk of serious adverse cardiovascular events associated with the use of varenicline among tobacco users.

Background

Areca nut (commonly known as betel nut) chewing has been shown to be associated with metabolic syndrome and cardiovascular disease (CVD). The mechanism by which betel nut ingestion could lead to development of CVD is not precisely known; however, dyslipidemia, hyperhomocysteinemia, hypertriglyceridemia and inflammation could be some of the potential risk factors. This study was undertaken to investigate the effects of two dosages of betel nut on homocysteinemia, inflammation and some of the components of metabolic syndrome, such as hypertriglyceridemia, low HDL-cholesterol, obesity and fasting hyperglycemia in a rat model.

Methods

Thirty-six adult female Sprague Dawley rats, aged 10–12 weeks were divided into three equal groups. Group-1 served as the control group (n = 12) and received water, whereas groups 2 and 3 were given water suspension of betel nut orally in two dosages, 30 mg and 60 mg, respectively for a period of 5 weeks. At the end of the fifth week, the animals were weighed and sacrificed, blood was collected and liver, kidney, spleen and stomach were removed for histological examination.

Plasma/serum was analyzed for glucose, total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, homocysteine, folate, vitamin B12 and N-acetyl-β-D-glucosaminidase (NAG) – a marker of inflammation.

Results

When the mean concentration values of 3 groups were compared using one way ANOVA followed by Tukey’s HSD-test, there was a significant increase in the concentration of total cholesterol (p = 0.04) in the group receiving 30 mg/day betel nut compared to the control group. However, administration of a higher dose of betel nut (60 mg/day) had no significant effect on the serum concentrations of glucose, total cholesterol, HDL-cholesterol, LDL-cholesterol, and NAG. Histological examination of spleen revealed a dose-dependent extramedullary hematopoiesis. No other remarkable change in the tissues (liver, kidney and stomach) was observed.

Mean serum/plasma levels of folate, vitamin B12 and homocysteine were not found to be significantly different in all the groups. Betel nut ingestion had no effect on the mean body weights of rats.

Conclusions

Low dosage of betel nut is found to be associated with hypercholesterolemia. However, betel nut ingestion is not associated with hyperhomocysteinemia, hypertriglyceridemia, hyperglycemia, inflammation and increase in body weight in a rat model.

Background

Cigarette smoking is associated with increased cardiovascular morbidity and mortality in the general population, but the effect of smoking on these outcomes in the dialysis population is less well studied.

Study Design

Systematic review and meta-analysis of cohort studies.

Setting & Population

Adults treated with long-term hemodialysis or peritoneal dialysis.

Selection Criteria for Included Studies

Cohort studies of unselected dialysis patients reporting the association between smoking status and cardiovascular morbidity and/or mortality.

Predictor

Smoking status (determined by patient report).

Outcomes

1) All-cause or cardiovascular mortality; 2) Incident cardiovascular events

Results

We identified 34 studies which fulfilled all inclusion criteria. Of these, 26 studies provide data on smoking and mortality and 10 (n = 6538) were included in a meta-analysis. The pooled hazard ratio for all-cause mortality in smokers compared to non-smokers was 1.65 (95% CI , 1.26–2.14; p<0.001) Eleven studies provided data on smoking and incident cardiovascular events, 5 (pooled n = 845) were included in a meta-analysis. The pooled hazard ratio for composite cardiovascular events in smokers compared to non-smokers was 1.01 (95% CI, 0.98–1.05, p 0.4)‥

Limitations

Data for these meta-analyses were heterogeneous. Few individual studies assessed smoking as the primary variable of interest.

Conclusions

Active smoking is associated with a significant increase in all-cause mortality in dialysis patients, although there was not a corresponding increased risk of cardiovascular events.

Background

Single traumatising events are associated with an elevated rate of psychological disorders in children and adolescents. To date, it remains unclear whether early psychological interventions can reduce longer term psychological maladjustment.

Objective

To systematically review the literature to determine the characteristics and efficacy of early psychological interventions in children and adolescents after a single, potentially-traumatising event.

Design

Systematic searches were conducted of all relevant bibliographic databases. Studies on early psychological interventions were included if the first session was conducted within 1 month of the event. Two independent observers assessed each study for eligibility, using pre-determined inclusion and exclusion criteria, and rated the study's methodological quality. A meta-analysis was conducted on the group effects between individuals allocated to intervention versus control groups. Hence, effect sizes (ES) and confidence intervals were computed as well as heterogeneity and analogue-to-the ANOVA analyses.

Results

Seven studies (including four randomised controlled trials) met the inclusion criteria. Depending on the specific outcome variable (e.g., dissociation, anxiety and arousal), small to large beneficial ES were noted. Although the meta-analysis revealed unexplained heterogeneity between the ES of the included studies, and although studies varied greatly with regards to their methodological quality and the interventions tested, findings suggest that early interventions should involve psycho-education, provide individual coping-skills and probably involve some kind of trauma exposure. Also, a stepped procedure that includes an initial risk screen and the provision of multiple sessions to those children at risk may be a promising strategy.

Conclusions

To date, research on the effectiveness of early interventions in children after a potentially traumatising event remains scarce. However, our review suggests that early interventions may be helpful.

In a systematic review and meta-analysis of 83 prognostic studies of C-reactive protein in coronary disease, Hemingway and colleagues find substantial biases, preventing them from drawing clear conclusions relating to the use of this marker in clinical practice.

Background

Systematic evaluations of the quality of research on a single prognostic biomarker are rare. We sought to evaluate the quality of prognostic research evidence for the association of C-reactive protein (CRP) with fatal and nonfatal events among patients with stable coronary disease.

Methods and Findings

We searched MEDLINE (1966 to 2009) and EMBASE (1980 to 2009) and selected prospective studies of patients with stable coronary disease, reporting a relative risk for the association of CRP with death and nonfatal cardiovascular events. We included 83 studies, reporting 61,684 patients and 6,485 outcome events. No study reported a prespecified statistical analysis protocol; only two studies reported the time elapsed (in months or years) between initial presentation of symptomatic coronary disease and inclusion in the study. Studies reported a median of seven items (of 17) from the REMARK reporting guidelines, with no evidence of change over time.

The pooled relative risk for the top versus bottom third of CRP distribution was 1.97 (95% confidence interval [CI] 1.78–2.17), with substantial heterogeneity (I2 = 79.5). Only 13 studies adjusted for conventional risk factors (age, sex, smoking, obesity, diabetes, and low-density lipoprotein [LDL] cholesterol) and these had a relative risk of 1.65 (95% CI 1.39–1.96), I2 = 33.7. Studies reported ten different ways of comparing CRP values, with weaker relative risks for those based on continuous measures. Adjusting for publication bias (for which there was strong evidence, Egger's p<0.001) using a validated method reduced the relative risk to 1.19 (95% CI 1.13–1.25). Only two studies reported a measure of discrimination (c-statistic). In 20 studies the detection rate for subsequent events could be calculated and was 31% for a 10% false positive rate, and the calculated pooled c-statistic was 0.61 (0.57–0.66).

Conclusion

Multiple types of reporting bias, and publication bias, make the magnitude of any independent association between CRP and prognosis among patients with stable coronary disease sufficiently uncertain that no clinical practice recommendations can be made. Publication of prespecified statistical analytic protocols and prospective registration of studies, among other measures, might help improve the quality of prognostic biomarker research.

Please see later in the article for the Editors' Summary

Editors' Summary

Background

Coronary artery disease is the leading cause of death among adults in developed countries. With age, fatty deposits called atherosclerotic plaques coat the walls of the arteries, the vessels that carry blood to the body's organs. Because they narrow the arteries, atherosclerotic plaques restrict blood flow. If plaques form in the arteries that feed the heart, the result is coronary artery disease, the symptoms of which include shortness of breath and chest pains (angina). If these symptoms only occur during exertion, the condition is called stable coronary artery disease. Coronary artery disease can cause potentially fatal heart attacks (myocardial infarctions). A heart attack occurs when a plaque ruptures and a blood clot completely blocks the artery, thereby killing part of the heart. Smoking, high blood pressure, high blood levels of cholesterol (a type of fat), diabetes, and being overweight are risk factors for coronary artery disease. Treatments for the condition include lifestyle changes and medications that lower blood pressure and blood cholesterol. Narrowed arteries can also be widened using a device called a stent or surgically bypassed.

Why Was This Study Done?

Clinicians can predict whether a patient with coronary artery disease is likely to have a heart attack by considering their risk factors. They then use this “prognosis” to help them manage the patient. To provide further help for clinicians, researchers are trying to identify prognostic biomarkers (molecules whose blood levels indicate how a disease might develop) for coronary artery disease. However, before a biomarker can be used clinically, it must be properly validated and there are concerns that there is insufficient high quality evidence to validate many biomarkers. In this systematic review and meta-analysis, the researchers ask whether the evidence for an association between blood levels of C-reactive protein (CRP, an inflammatory protein) and subsequent fatal and nonfatal events affecting the heart and circulation (cardiovascular events) among patients with stable coronary artery disease supports the routine measurement of CRP as recommended in clinical practice guidelines. A systematic review uses predefined criteria to identify all the research on a given topic; a meta-analysis is a statistical method for combining the results of several studies.

What Did the Researchers Do and Find?

The researchers identified 83 studies that investigated the association between CRP levels measured in people with coronary artery disease and subsequent cardiovascular events. Their examination of these studies revealed numerous reporting and publication short-comings. For example, none of the studies reported a prespecified statistical analysis protocol, yet analyses should be prespecified to avoid the choice of analytical method biasing the study's results. Furthermore, on average, the studies only reported seven of the 17 recommended items in the REMARK reporting guidelines, which were designed to improve the reporting quality of tumor biomarker prognostic studies. The meta-analysis revealed that patients with a CRP level in the top third of the distribution were nearly twice as likely to have a cardiovascular event as patients with a CRP in the bottom third of the distribution (a relative risk of 1.97). However, the outcomes varied considerably between studies (heterogeneity) and there was strong evidence for publication bias—most published studies were small and smaller studies were more likely to report higher relative risks. Adjustment for publication bias reduced the relative risk associated with high CRP levels to 1.19. Finally, nearly all the studies failed to calculate whether CRP measurements discriminated between patients likely and unlikely to have a subsequent cardiovascular event.

What Do These Findings Mean?

These findings suggest that, because of multiple types of reporting and publication bias, the size of the association between CRP levels and prognosis among patients with stable coronary artery disease is extremely uncertain. They also suggest that CRP measurements are unlikely to add anything to the prognostic discrimination achieved by considering blood pressure and other standard clinical factors among this patient group. Thus, the researchers suggest, the recommendation that CRP measurements should be used in the management of patients with stable coronary artery disease ought to be removed from clinical practice guidelines. More generally, these findings increase concerns about the quality of research into prognostic biomarkers and highlight areas that need to be changed, the most fundamental of which is the need to preregister studies on prognostic biomarkers and their analytic protocols.

Additional Information

Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000286.

The MedlinePlus Encyclopedia has pages on coronary artery disease and C-reactive protein (in English and Spanish)

MedlinePlus provides links to other sources of information on heart disease

The American Heart Association provides information for patients and caregivers on all aspects of cardiovascular disease, including information on the role of C-reactive protein in heart disease

Information is available from the British Heart Foundation on heart disease and keeping the heart healthy

Wikipedia has pages on biomarkers and on C-reactive protein (note that Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)

The EQUATOR network is a resource center for good reporting of health research studies

Background

A number of investigators have evaluated the association between the ABCB1 polymorphism and clopidogrel responding, but the results have been inconclusive. To examine the risk of high platelet activity and poor clinical outcomes associated with the ABCB1 C3435T polymorphism in CAD patients on clopidogrel, all available studies were included in the present meta-analysis.

Methods

We performed a systematic search of PubMed, Scopus and the Cochrane library database for eligible studies. Articles meeting the inclusion criteria were comprehensively reviewed, and the available data were accumulated by the meta-analysis.

Results

It was demonstrated that the ABCB1 C3435T variation was associated with the risk of early major adverse cardiovascular events (MACE) (T vs. C OR, 1.34; 95% CI, 1.10 to 1.62; P = 0.003; TT vs. CC: OR, 1.77; 95% CI, 1.19 to 2.63; P = 0.005; CT + TT vs.CC: OR, 1.48; 95% CI, 1.06 to 2.06; P = 0.02) and the polymorphism was also associated with the risk of the long-term MACE in patients on clopidogrel LD 300 mg (T vs. C: OR, 1.28; 95% CI, 1.10 to 1.48; P = 0.001; TT vs. CC: OR, 1.59; 95% CI, 1.19 to 2.13; P = 0.002; CT + TT vs.CC: OR, 1.39; 95% CI, 1.08 to 1.79; P = 0.01). The comparison of TT vs. CC was associated with a reduction in the outcome of bleeding (TT vs. CC: OR, 0.51; 95% CI, 0.40 to 0.66; P<0.00001). However, the association between ABCB1 C3435T polymorphism and platelet activity and other risk of poor clinical outcomes was not significant.

Conclusions

The evidence from our meta-analysis indicated that the ABCB1 C3435T polymorphism might be a risk factor for the MACE in patients on clopidogrel LD 300 mg, and that TT homozygotes decreased the outcome of bleeding compared with CC homozygotes.

Abstract

Objective

The aim of this study was to examine whether there are ethnic differences in the association of triglycerides (TG) with waist circumference (WC), blood pressure, high-density lipoprotein cholesterol (HDL-C), fasting glucose, and insulin resistance and to examine the disparities in the prevalence of the metabolic syndrome components between African Americans and non-Hispanic whites who do not have hypertriglyceridemia.

Methods

This study used the baseline data from the Multi-Ethnic Study of Atherosclerosis (MESA) study. The analysis included non-Hispanic whites (N = 2,427) and African Americans (N = 1,519) aged 45–84 years free of clinically evident cardiovascular disease and diabetes at baseline. The revised National Cholesterol Education Program (NCEP) criteria were used to define the metabolic syndrome and its components.

Results

African Americans had lower prevalence of elevated TG as compared with non-Hispanic whites. The association of TG with other components of the metabolic syndrome appeared to be similar between African Americans and non-Hispanic whites except for one. There was significant association of TG with WC among white women but not among African American women after adjusting for demographic and other variables (P for interaction of TG with ethnicity <0.001). In participants with TG < 150 mg/dL, African American women had higher prevalence rates than white women of abdominal obesity, elevated blood pressure, low HDL-C, elevated fasting glucose and homeostasis model assessment of insulin resistance (HOMA-IR). In men, the prevalence rates of high blood pressure, elevated fasting glucose, and HOMA-IR were significantly higher in African Americans than in whites.

Conclusions

The study findings suggest that further evaluation is warranted regarding the cutoffs for elevated TG and its clustering effect with other cardiometabolic risk factors on predicting risk for diabetes and cardiovascular disease (CVD) in African Americans.

AIM

Age-related macular degeneration (AMD) is the leading cause of blindness in the developed world and complement factor H (CFH) polymorphism has been found to associate with the AMD. To investigate whether the Y402H variant in CFH is associated with AMD in Chinese populations, a systematic review and meta-analysis were performed to estimate the magnitude of the gene effect and the possible mode of action.

METHODS

A meta-analysis was performed using data available from ten case-control studies assessing association between the CFH Y402H polymorphism and AMD in Chinese populations involving 1538 AMD. Data extraction and study quality assessment were performed in duplicate. Summary odds ratios (ORs) and 95% confidence intervals (CIs) an allele contrast and genotype contrast were estimated using fixed- effects models. The Q-statistic test was used to assess heterogeneity, and Funnel plot was used to evaluate publication bias.

RESULTS

Seven of ten case-control studies were neovascular AMD, and few studies came from west and north of China. There was strong evidence for association between CFH and AMD in Chinese population, with those having risk allele C 2.35 times more likely to have AMD than subjects with T allele. Evidence of publication bias was not observed in our meta-analysis.

CONCLUTION

This meta-analysis summarizes the strong evidence for an association between CFH and AMD in Chinese and indicates each C allele increasing the odds of AMD by 2.33-fold.But more evidences about the relation between CFH polymorphism and different type of Chinese AMD from various district were needed.

In this systematic review and meta-analysis, Giardia lamblia was not associated with acute pediatric diarrhea in nonindustrialized settings but was positively linked to persistent diarrhea.

We performed a systematic literature review and meta-analysis examining the association between diarrhea in young children in nonindustrialized settings and Giardia lamblia infection. Eligible were case/control and longitudinal studies that defined the outcome as acute or persistent (>14 days) diarrhea, adjusted for confounders and lasting for at least 1 year. Data on G. lamblia detection (mainly in stools) from diarrhea patients and controls without diarrhea were abstracted. Random effects model meta-analysis obtained pooled odds ratios (ORs) and 95% confidence intervals (CIs). Twelve nonindustrialized-setting acute pediatric diarrhea studies met the meta-analysis inclusion criteria. Random-effects model meta-analysis of combined results (9774 acute diarrhea cases and 8766 controls) yielded a pooled OR of 0.60 (95% CI, .38–.94; P = .03), indicating that G. lamblia was not associated with acute diarrhea. However, limited data suggest that initial Giardia infections in early infancy may be positively associated with diarrhea. Meta-analysis of 5 persistent diarrhea studies showed a pooled OR of 3.18 (95% CI, 1.50–6.76; P < .001), positively linking Giardia with that syndrome. The well-powered Global Enteric Multicenter Study (GEMS) is prospectively addressing the association between G. lamblia infection and diarrhea in children in developing countries.

Background

Aspirin and clopidogrel monotherapies are effective treatments for preventing vascular disease. However, new evidence has emerged regarding the use of combined aspirin and clopidogrel therapy to prevent cardiovascular events. We therefore performed a comprehensive systematic review and meta-analysis to evaluate the benefits and harms of combined aspirin and clopidogrel therapy on major cardiovascular outcomes.

Methodology/Principal Findings

We systematically searched Medline, Embase, the Cochrane Central Register of Controlled Trials, reference lists of articles, and proceedings of major meetings to identify studies to fit our analysis. Eligible studies were randomized controlled trials assessing the effect of combined aspirin and clopidogrel therapy compared with aspirin or clopidogrel monotherapy. We identified 7 trials providing data with a total of 48248 patients. These studies reported 5134 major cardiovascular events, 1626 myocardial infarctions, 1927 strokes, and 1147 major bleeding events. Overall, the addition of aspirin to clopidogrel therapy as compared to single drug therapy resulted in a 9% RR reduction (95%CI, 2 to 17) in major cardiovascular events, 14% RR reduction (95%CI, 3 to 24) in myocardial infarction, 16% RR reduction (95%CI, 1 to 28) in stroke, and 62% RR increase (95%CI, 26 to 108) in major bleeding events. We also present the data as ARR to explore net value as the reduction in cardiovascular events. Overall, we observed that combined therapy yielded 1.06% decrease (95%CI, 0.23% to 1.99%) in major cardiovascular events and 1.23% increase (95%CI, 0.52% to 2.14%) in major bleeding events.

Conclusion/Significance

Although the addition of aspirin to clopidogrel resulted in small relative reductions in major cardiovascular events, myocardial infarction, and stroke, it also resulted in a relative increase in major bleeding events. In absolute terms the benefits of combined therapy, a 1.06% reduction in major cardiovascular events, does not outweigh the harms, a 1.23% increase in major bleeding events.

Background

Adverse consequences of medical interventions are a source of concern, but clinical trials may lack power to detect elevated rates of such events, while observational studies have inherent limitations. Meta-analysis allows the combination of individual studies, which can increase power and provide stronger evidence relating to adverse events. However, meta-analysis of adverse events has associated methodological challenges. The aim of this study was to systematically identify and review the methodology used in meta-analyses where a primary outcome is an adverse or unintended event, following a therapeutic intervention.

Methods

Using a collection of reviews identified previously, 166 references including a meta-analysis were selected for review. At least one of the primary outcomes in each review was an adverse or unintended event. The nature of the intervention, source of funding, number of individual meta-analyses performed, number of primary studies included in the review, and use of meta-analytic methods were all recorded. Specific areas of interest relating to the methods used included the choice of outcome metric, methods of dealing with sparse events, heterogeneity, publication bias and use of individual patient data.

Results

The 166 included reviews were published between 1994 and 2006. Interventions included drugs and surgery among other interventions. Many of the references being reviewed included multiple meta-analyses with 44.6% (74/166) including more than ten. Randomised trials only were included in 42.2% of meta-analyses (70/166), observational studies only in 33.7% (56/166) and a mix of observational studies and trials in 15.7% (26/166). Sparse data, in the form of zero events in one or both arms where the outcome was a count of events, was found in 64 reviews of two-arm studies, of which 41 (64.1%) had zero events in both arms.

Conclusions

Meta-analyses of adverse events data are common and useful in terms of increasing the power to detect an association with an intervention, especially when the events are infrequent. However, with regard to existing meta-analyses, a wide variety of different methods have been employed, often with no evident rationale for using a particular approach. More specifically, the approach to dealing with zero events varies, and guidelines on this issue would be desirable.

Background

This systematic review and meta-analysis aims at assessing the composition and performance of care management models evaluated in the last decade and their impact on patient important outcomes.

Methods

A comprehensive literature search of electronic bibliographic databases was performed to identify care management trials in type 2 diabetes. Random effects meta-analysis was used when feasible to pool outcome measures.

Results

Fifty-two studies were eligible. Most commonly reported were surrogate outcomes (such as HbA1c and LDL), followed by process measures (clinic visit or testing frequency). Less frequently reported were quality of life, patient satisfaction, self-care, and healthcare utilization. Most care management modalities were carved out from primary care. Meta-analysis demonstrated a statistically significant but trivial reduction of HbA1c (weighted difference in means -0.21%, 95% confidence interval -0.40 to -0.03, p < .03) and LDL-cholesterol (weighted difference in means -3.38 mg/dL, 95% confidence interval -6.27 to -0.49, p < .02).

Conclusions

Most care management programs for patients with type 2 diabetes are 'carved-out', accomplish limited effects on metabolic outcomes, and have unknown effects on patient important outcomes. Comparative effectiveness research of different models of care management is needed to inform the design of medical homes for patients with chronic conditions.