The Weight Loss Maintenance Trial (WLM) was a multi-center, randomized trial comparing two weight loss maintenance interventions, a personal contact program (PC) with primarily telephone-based monthly contacts, and an Internet-based program (IT), to a self-directed control group, among overweight or obese individuals at high cardiovascular risk. This paper describes implementation costs of both interventions as well as IT development costs.
Resources were micro-costed in 2006 dollars from the primary perspective of a sponsoring healthcare system considering adopting an extant intervention, rather than developing its own. Costs were discounted at 3% annually. Length of trial participation was 30 months (randomization during February-November 2004). IT development costs were assessed over 36 months. Univariate and multivariate, including probabilistic, sensitivity analyses were performed.
Total discounted IT development costs over 36 months were $839,949 ($2,414 per IT participant). Discounted 30-month implementation costs for 342 PC participants were $537,242 ($1,571 per participant), and for 348 IT participants, were $214,879 ($617 per participant). Under all plausible scenarios, PC implementation costs exceeded IT implementation costs.
Costs of implementing and operating an Internet-based intervention for weight loss maintenance were substantially less than analogous costs of an intervention using standard phone and in-person contacts, and are of a magnitude that would be attractive to many health systems, subject to demonstration of cost-effectiveness.
Cost; weight loss; Internet; behavioral intervention; implementation
Glycemic control is improved more after gastric bypass surgery (GBP) than after equivalent diet-induced weight loss in patients with morbid obesity and type 2 diabetes mellitus. We applied metabolomic profiling to understand the mechanisms of this better metabolic response after GBP. Circulating amino acids (AAs) and acylcarnitines (ACs) were measured in plasma from fasted subjects by targeted tandem mass spectrometry before and after a matched 10-kilogram weight loss induced by GBP or diet. Total AAs and branched-chain AAs (BCAAs) decreased after GBP, but not after dietary intervention. Metabolites derived from BCAA oxidation also decreased only after GBP. Principal components (PC) analysis identified two major PCs, one composed almost exclusively of ACs (PC1) and another with BCAAs and their metabolites as major contributors (PC2). PC1 and PC2 were inversely correlated with pro-insulin concentrations, the C-peptide response to oral glucose, and the insulin sensitivity index after weight loss, whereas PC2 was uniquely correlated with levels of insulin resistance (HOMA-IR). These data suggest that the enhanced decrease in circulating AAs after GBP occurs by mechanisms other than weight loss and may contribute to the better improvement in glucose homeostasis observed with the surgical intervention.
Facing critically low return per dollar invested on clinical research and clinical care, the American biomedical enterprise is in need of a significant transformation. A confluence of high-throughput “omic” technologies and increasing adoption of the electronic health record has fueled excitement for a new paradigm for biomedical research and practice. The ability to simultaneously measure thousands of molecular variables and assess their relationships with clinical data collected during the course of care could enable reclassification of disease not only by gross phenotypic observation but according to underlying molecular mechanism and influence of social determinants.In turn, this reclassification could enable development of targeted therapeutic interventions as well as disease prevention strategies at the individual and population levels.
The MURDOCK Study consists of distinct project “horizons” or stages. Horizon 1 entailed the generation and analysis of molecular data for existing large,clinically well-annotated cohorts in four disease areas. Horizon 1.5 involves creating and maintaining a 50,000-person,community volunteer registry for biomarker signature validation and prospective studies, including integration of environmental and social data. Horizon 2 leverages and prospectively recruits Horizon 1.5 volunteers, and extends the study to additional disease areas of interest. Horizon 3 will expand the study through regional, national,and international partnerships.
The MURDOCK Study embodies a new model of team science investigation and represents a significant resource for translational research. The study team invites inquiries to form new collaborations to exploit the rich resources provided by these biospecimens and associated study data.
Stratified medicine; personalized medicine; biomarkers; disease reclassification; community registry; biorepository
To pilot test a culturally adapted behavioral weight loss intervention in obese and overweight Latino adults.
Latino community organization in Durham, North Carolina.
Overweight and obese, self-identified Latinos ≥18 years old.
Intervention consisted of 20 weekly group sessions (90–120 minutes each) incorporating motivational interviewing techniques. The intervention goal was weight loss by adopting the Dietary Approach to Stop Hypertension (DASH) dietary pattern, increasing physical activity, and reducing caloric intake. The cultural adaptation included foods and physical activities commonly used in the Latino culture, using a Spanish-speaking interventionist, and conducting the intervention at a local Latino community organization.
Main outcome measures
Weight, body mass index (BMI), blood pressure, dietary pattern, and physical activity were measured at baseline and at 20 weeks.
A total of 56 participants are included in the final analysis. The average weight loss was 5.1 lbs (95% CI −8.7 to −1.5; P=.006); and there was a reduction in BMI of 1.3 kg/m2 (95% CI −2.2 to −0.5; P=.002) at 20 weeks. Systolic blood pressure decreased by 2.6 mm Hg (95% CI −4.7 to −0.6; P=.013).
A culturally adapted behavioral intervention for the treatment of overweight and obesity is potentially effective in a diverse group of Latino adults.
Obesity; Overweight; Latinos; Cultural; Intervention; Weight Loss
The authors sought to examine the relationship between physician characteristics and patient blood pressure (BP) in participants enrolled in the Hypertension Improvement Project (HIP). In this cross-sectional study using baseline data of HIP participants, the authors used multiple linear regression to examine how patient BP was related to physician characteristics, including experience, practice patterns, and clinic load. Patients had significantly lower systolic BP (SBP) (−0.2 mm Hg for every 1% increase, P=.008) and diastolic BP (DBP) (−0.1 mm Hg for every 1% increase, P=.0007) when seen by physicians with a higher percentage of patients with hypertension. Patients had significantly higher SBP (0.8 mm Hg for every 1% increase, P=.002) when seen by physicians with a higher number of total clinic visits per day. Patients had significantly lower DBP (−4.4 mm Hg decrease, P=.0002) when seen by physicians with inpatient duties. Physician’s volume of patients with hypertension was related to better BP control. However, two indicators of a busy practice had conflicting relationships with BP control. Given the increasing time demands on physicians, future research should examine how physicians with a busy practice are able to successfully address BP in their patients.
Lifestyle behaviors such as reducing weight if overweight or obese, reducing salt intake, exercising, reducing alcohol intake, quitting smoking, and eating a healthy diet are related to the prevention and control of chronic diseases. However the amount of lifestyle advice provided by clinicians has been declining over the last decade.
In 2002, a telephone survey was conducted to assess the quality of preventive care offered by health care providers. The study was a cross-sectional observational study of a randomly selected sample of 516 diverse individuals in Durham County, North Carolina. Information regarding age, sex, race, education, health conditions, and self-reported receipt of lifestyle advice was examined in the study.
The odds of receiving advice to engage in preventive lifestyle behaviors were significantly higher for those with a pre-existing diagnosis of diabetes or hypertension and for participants reporting poor health status. For example, the odds of receiving advice to control or lose weight was 8.32 (95% CI, 2.65, 26.15) among individuals reporting a diagnosis of diabetes. Similarly, the odds of reporting “receiving advice to reduce salt intake” was 6.97 (95% CI, 3.74, 13.00) among subjects reporting a diagnosis of hypertension.
The results are from a cross-sectional study of a sample of individuals in only one county. Additionally, the results are based on patient self-reported information, which could be subject to recall and social desirability bias.
Patients with identified health problems were more likely than others to report being advised to adopt healthy lifestyle recommendations. Future research should examine methods to encourage health care providers to offer lifestyle advice to those without pre-existing illness.
lifestyle; provider; prevention
Potential blood pressure- (BP-) lowering mechanisms of the DASH dietary pattern were measured in 20 unmedicated hypertensive adults in a controlled feeding study. At screening, participants averaged 44.3 ± 7.8 years, BMI 33.9 ± 6.6 Kg/m2, and BP 144.2 ± 9.38/88.5 ± 6.03 mmHg. All consumed a control diet for one week, then were randomized to control or DASH for another two weeks (week one and two). With DASH, but not controls, SBP fell by 10.65 ± 12.89 (P = 0.023) and 9.60 ± 11.23 (P = 0.039) mmHg and DBP by 5.95 ± 8.01 (P = 0.069) and 8.60 ± 9.13 mmHg (P = 0.011) at the end of week one and two, respectively. Univariate regressions showed that changes in urinary sodium/potassium ratio (β = 1.99) and plasma renin activity (β = −15.78) and percent change in plasma nitrite after hyperemia were associated with SBP changes at week one (all P < 0.05). Plasma nitrite following hyperemia showed a treatment effect (P = 0.014) and increased at week two (P = 0.001). Pulse wave velocity decreased over time with DASH (trend P = 0.019), and reached significance at week two (P = 0.026). This response may be mediated by an improvement in upregulation of nitric oxide bioavailability. Early natriuresis and reductions in oxidative stress cannot be ruled out. Future studies are needed to verify these findings, assess the possibility of earlier effects, and examine other potential mediators.
To ascertain accuracy of self-reported height, weight (and hence body mass index) in African American and white women and men older than 70 years of age.
The sample consisted of cognitively intact participants at the third in-person wave (1992–1993) of the Duke Established Populations for Epidemiologic Studies of the Elderly (age 71 and older, N = 1761; residents of five adjacent counties, one urban, four rural). During in-person, in-home interviews using trained interviewers, height and weight were self-reported (and measured later in the same visit using a standardized protocol), and information were obtained on race, sex, and age.
Accuracy of self-reported height and weight was high (intraclass correlation coefficient 0.85 and 0.97, respectively) but differed as a function of race and age. On average, all groups overestimated their height; whereas (non-Hispanic) white men and women underestimated their weight, African Americans overestimated their weight. Overestimation of height and weight was more marked in persons 85 years and older. Specificity for overweight (body mass index [kg/m2] ≥ 25) and obesity (body mass index ≥ 30) ranged from 0.90 to 0.99 for African Americans and whites, but sensitivity was better for African Americans (overweight: 0.81, obesity: 0.89), than for whites (0.66 and 0.57, respectively).
Height and weight self-reported by African Americans and whites over the age of 70 can be used in epidemiological studies, with greater caution needed for self-reports of whites, and of persons 85 years of age or older.
Height; Weight; Body mass index; Elderly; African American
This study examines the association between microalbuminuria and the development of proteinuria among HIV-infected persons.
948 subjects provided urine samples for albumin, protein, and creatinine measurements semiannually. Microalbuminuria was an albumin-to-creatinine ratio of >30 mg/gm. Proteinuria was a protein-to-creatinine ratio of ≥0.350 mg/mg. The progression from microalbuminuria to proteinuria was described.
At baseline, 69.4% had no detectable proteinuria, 20.2% had microalbuminuria, and 10.4% had proteinuria. Subjects with microalbuminuria and proteinuria were more likely to be black (p=0.03), have lower CD4+ counts (p=0.02,0.0001 compared to subjects without abnormal proteinuria, respectively), and have a higher HIV RNA level (p=0.08,0.04). Among 658 subjects with normal urine protein, 82.7% continued to have no abnormality, 14.3% developed microalbuminuria, and 3.0% developed proteinuria. Subjects without baseline proteinuria (i.e. either normal protein excretion or microalbuminuria) who developed proteinuria were more likely to have microalbuminuria (p=0.001), a lower CD4+ count (p=0.06), and a higher plasma HIV RNA (p=0.03) than those who did not progress to proteinuria. In multivariate analysis, only microalbuminuria remained associated with the development of proteinuria (OR=2.9; 95% CI 1.5, 5.5; p=0.001).
Microalbuminuria predicts the development of proteinuria among HIV-infected persons. Because proteinuria has been linked to poorer outcomes, strategies to affect microalbuminuria should be tested.
HIV-1; microalbuminuria; proteinuria; HIVAN; urine
Essential hypertension results from the interaction of several genetic and environmental factors. Identification of genetic factors that modulate blood pressure (BP) response to interventions can lead to improved strategies for prevention and control. The purpose of this study was to identify genes that modulate BP response to dietary interventions.
We used data and samples collected in two randomized feeding studies to determine the extent to which genetic architecture is associated with the effect on BP of sodium intake and the Dietary approaches to Stop Hypertension (DASH) dietary pattern. Participants in both trials were adults with above-optimal BP or unmedicated stage 1 hypertension. Genomic DNa was typed for several candidate genes.
The effect of sodium intake on BP differed by genotype at the angiotensinogen, β2-adrenergic receptor, and kallikrein loci. The effect of DASH dietary pattern on BP differed by genotype at the β2-adrenergic receptor locus.
These findings have implications for understanding the mechanism(s) through which diet affects BP, the heterogeneity of these effects, and the extent to which dietary interventions can modulate genetic predisposition.
blood pressure; DASH; diet; genetics; hypertension; sodium
To assess the feasibility of a culturally tailored behavioral intervention for improving hypertension-related health behaviors in Hispanic/Latino adults.
Feasibility pilot study in a community health center and a Latino organization in Durham, North Carolina (NC).
The culturally adapted behavioral intervention consisted of 6 weekly group sessions incorporating motivational interviewing techniques. Goals included weight loss if overweight, adoption of the Dietary Approaches to Stop Hypertension (DASH) dietary pattern, and increased physical activity. Participants were also encouraged to monitor their daily intake of fruits, vegetables, dairy and fat, and to record physical activity. Cultural adaptations included conducting the study in familiar places, using Spanish-speaking interventionist, culturally-appropriate food choices, and physical activity.
Systolic blood pressure, weight, body mass index (BMI), exercise, and dietary pattern were measured at baseline and at 6 weeks follow-up. Qualitative evaluations of the recruitment process and the intervention were also conducted.
There were 64 potential participants identified via health care provider referrals (33%), printed media (23%), and direct contact (44%). Seventeen participants completed the intervention and had main outcome data available. Participants “strongly agreed/ agreed” that the group sessions provided them with the tools they needed to achieve weight loss, blood pressure control, and the possibility of sustaining the lifestyle changes after completing the intervention. At the end of the intervention, all physiological, diet, and exercise outcomes were more favorable, with the exception of fat. After 6 weeks, systolic blood pressure decreased an average of −10.4 ± 10.6 mmHg, weight decreased 1.5 ± 3.2 lbs, BMI decreased 0.3 ± 0.5, and physical activity increased 40 minutes per week.
Our findings suggest that lifestyle interventions for preventing and treating hypertension are feasible and potentially effective in the Hispanic/Latino population.
Hypertension; Hispanic; Latino; non pharmacologic interventions; blood pressure control; weight loss; DASH dietary pattern; lifestyle intervention
Despite widely publicized hypertension treatment guidelines for physicians and lifestyle recommendations for patients, blood pressure control rates remain low. In community-based primary care clinics, we performed a nested, 2×2 randomized, controlled trial of physician intervention vs. control and/or patient intervention vs. control. Physician Intervention included internet-based training, self-monitoring, and quarterly feedback reports. Patient Intervention included 20 weekly group sessions followed by 12 monthly phone counseling contacts, and focused on weight loss, DASH dietary pattern, exercise, and reduced sodium intake. The primary outcome was change in systolic blood pressure at 6 months.
Eight primary care practices (32 physicians) were randomized to Physician Intervention or Control. Within those practices, 574 patients were randomized to Patient Intervention or Control. Patients’ mean age was 60 years, 61% female, 37% African American. BP data were available for 91% of patients at 6 months. The main effect of Physician Intervention on systolic blood pressure at 6 months, adjusted for baseline pressure, was 0.3 mmHg (95% CI −1.5 to 2.2; p = 0.72). The main effect of the Patient Intervention was −2.6 mmHg (95% CI −4.4, −0.7; p = 0.01). The interaction of the 2 interventions was significant (p = 0.03); the largest impact was observed with the combination of Physician and Patient Intervention (−9.7 ± 12.7 mmHg). Differences between treatment groups did not persist at 18 months. Combined physician and patient intervention lowers blood pressure; future research should focus on enhancing effectiveness and sustainability of these interventions.
Hypertension; blood pressure; behavioral intervention; quality improvement; lifestyle; DASH dietary pattern
The Take Control of Your Blood Pressure trial evaluated the effect of a multicomponent telephonic behavioral lifestyle intervention, patient self-monitoring, and both interventions combined compared with usual care on reducing systolic blood pressure during 24 months. The combined intervention led to a significant reduction in systolic blood pressure compared with usual care alone. We examined direct and patient time costs associated with each intervention.
We conducted a prospective economic evaluation alongside a randomized controlled trial of 636 patients with hypertension participating in each study intervention. Medical costs were estimated using electronic data representing medical services delivered within the health system. Intervention-related costs were derived using information collected during the trial, administrative records, and published unit costs.
During 24 months, patients incurred a mean of $6965 (SD, $22,054) in inpatient costs and $8676 (SD, $9368) in outpatient costs, with no significant differences among the intervention groups. With base-case assumptions, intervention costs were estimated at $90 (SD, $2) for home blood pressure monitoring, $345 (SD, $64) for the behavioral intervention ($31 per telephone encounter), and $416 (SD, $93) for the combined intervention. Patient time costs were estimated at $585 (SD, $487) for home monitoring, $55 (SD, $16) for the behavioral intervention, and $741 (SD, $529) for the combined intervention.
Our analysis demonstrated that the interventions are cost-additive to the health care system in the short term and that patients’ time costs are nontrivial.
Costs and Cost Analysis; Hypertension; Patient Compliance
Less than 40% of Americans with hypertension have adequate blood pressure (BP) control.
To compare two self-management interventions for improving BP control among hypertensive patients.
A 2 by 2 randomized trial stratified by enrollment site and patient literacy status with two-year follow-up (5/2004-1/2008).
Two university-affiliated primary care clinics.
636 patients were randomized (31% recruitment rate) among the 2060 eligible hypertensive patients.
Research assistants randomized eligible patients via a centralized blinded and stratified randomization algorithm to receive either: 1) usual care; 2) bi-monthly tailored nurse-administered telephone intervention targeting hypertension-related behaviors; 3) BP monitoring consisting of measuring BP three times per week, or; 4) a combination of the two interventions.
The primary outcome was BP control evaluated at six-month intervals over 24 months. 475 (75%) completed the 24-month BP follow-up.
Improvements in proportion of BP control for the intervention groups relative to the usual care group at 24 months were: behavioral group, 4.3% (95% CI: −4.5%, 12.9); home BP monitoring group, 7.6% (95% CI: −1.9%, 17.0%); and, combined interventions, 11.0% (95% CI: 1.9%, 19.8%). For systolic BP, relative to usual care, the 24 month difference was, +0.6 mmHg (95% CI: −2.2, 3.4) for the behavioral intervention group, −0.6 mmHg (95% CI: −3.6, 2.3) for the home monitoring group, and −3.9 mmHg (95% CI: −6.9, −0.9) for the combined interventions. Similar patterns were observed for diastolic BP at 24 months.
Changes in medication use and diet were only monitored in intervention participants; 25% lacked 24 month outcome data; 73% had adequate BP control at baseline; the study setting was an academic health center, all factors that potentially limit generalizability.
Combined home BP monitoring and tailored behavioral telephone intervention improved BP control, systolic BP, and diastolic BP at 24 months relative to usual care.
Hypertension; Lifestyle; Clinical Trial; Self-management; Adherence
Dietary studies designed to lower urinary albumin excretion rate (AER) typically reduce protein by increasing lower protein plant foods and reducing higher protein animal products.
We evaluated AER while increasing protein intake in the Dietary Approaches to Stop Hypertension (DASH) Trial (randomized, parallel group, 8 week controlled feeding).
Setting & Participants
378 individuals without diabetes with prehypertension or stage I hypertension.
The DASH diet, 18% energy from protein, emphasizes, among other features, lowfat dairy products; and the fruit/vegetable (FV) and Control diets, each with 15% energy from protein.
We measured AER by immunoassay and covariates at baseline and after 8 weeks.
Baseline AER had geometric mean ± standard error 4.0 ± 0.2 mg/24hr. Among 285 participants with baseline AER<7 mg/24hr, AER was unchanged by diet treatment (geometric mean 2.5 ± 0.2 mg/24hr in Control, 3.0 ± 0.2 mg/24hr in FV, 2.8 ± 0.2 mg/24hr in DASH). In contrast, among 93 participants with baseline AER ≥7 mg/24hr, end of feeding AER was lower in FV (6.6 ± 1.0 mg/24hr) than in Control (11.4 ± 1.8 mg/24hr (p=0.01) or DASH (11.7 ± 1.6 mg/24hr p = 0.005). The DASH and control diets were not different (p=0.9).
Long term AER change not studied.
Reduction in AER after 8 weeks occurred only in those with high normal baseline AER in FV, in a pattern distinct from blood pressure reduction. The DASH diet did not increase AER despite 3% increase in energy from protein.
Women with polycystic ovary syndrome (PCOS) commonly have insulin resistance. Insulin resistance is associated with marked abnormalities of lipoprotein size and subclass particle concentration. The purpose of this study was to examine the effects of a moderate-intensity exercise program without weight loss on lipoprotein profiles in women with PCOS.
Thirty-seven sedentary PCOS women were randomized to either an 8–12-week ramp-up followed by a12-week moderate-intensity exercise program (16–24 weeks total, ~228 min/wk at 40–60% peak VO2, n=21) or control (no change in lifestyle, n=16). PCOS was defined as < 8 menses per year and hyperandrogenism (biochemical or clinical with Ferriman-Gallwey score >8). Fasting lipoprotein profiles were obtained before and after the intervention. Nuclear magnetic resonance spectroscopy (NMR) was used to quantify the following: average particle size, total and subclass concentrations of HDL, LDL and VLDL particles, and calculated HDL cholesterol, triglycerides, and VLDL triglycerides. Wilcoxon exact rank sums tests were used to compare changes in these parameters in the exercise group relative to controls.
Twenty women (8 exercisers, 12 controls) completed the study. Comparing exercisers to controls, significant changes were seen in concentrations of the following lipoprotein parameters which are associated with decreased insulin resistance: decreased large VLDL (p=0.007), calculated triglycerides (p=0.003), VLDL triglycerides (p=0.003), and medium/small HDL (p=0.031); and increased large HDL (p=0.002) and average HDL size (p=0.001).
In this trial, moderate-intensity exercise without significant weight loss improved several components of the lipoprotein profiles of women with PCOS. These findings support the beneficial role of moderate exercise in this high-risk population.
PCOS; cholesterol; lipids; nuclear magnetic resonance spectroscopy
Prader-Willi syndrome (PWS) is associated with failure to thrive in infancy and progressive hyperphagia and obesity in childhood. This progressive weight gain is associated with hyperghrelinaemia and increased insulin sensitivity. The role of ghrelin excess in the pathogenesis of obesity is unclear.
To determine if high ghrelin levels precede the onset of obesity in young PWS children.
Design and methods
A cross-sectional study of 33 infants with PWS and 28 healthy control subjects (C). Fasting ghrelin and other satiety hormones were measured.
Median total serum ghrelin in young children with PWS trended higher, but did not differ significantly from those in C of similar age, weight-for-age z-score and sex. However, there was more variability in ghrelin concentrations of young PWS. Eleven of 33 PWS subjects had ghrelin levels greater than the 95th percentile for ghrelin values in the C subjects (> 2871 pg/ml). Six of the PWS subjects with high ghrelin levels had weight-for-age z-scores < 0. Ghrelin concentrations in PWS and C infants exceeded those in older children. In youngsters with PWS, leptin was higher, suggesting a relative excess of fat to lean body mass and plasma adiponectin was increased.
Young infants with PWS who have not yet developed hyperphagia or obesity have median fasting ghrelin levels similar to controls. However, a subset (33%) of young PWS is hyperghrelinaemic; approximately one-half of those with hyperghrelinaemia have BMI z-score < 0. The age-related decline in ghrelin is blunted in PWS.
Prader–Willi syndrome (PWS) is a genetic syndrome characterized by relative hypoinsulinaemia and normal or increased insulin sensitivity despite profound obesity. We hypothesized that this increased insulin sensitivity is mediated by increased levels of total and high molecular weight adiponectin and associated with changes in levels of satiety hormones.
Design, patients and measurements
We measured total adiponectin and its isoforms [high molecular weight (HMW), middle molecular weight (MMW) and low molecular weight (LMW) adiponectin] and satiety hormones in 14 children with PWS [median age 11.35 years, body mass index (BMI) Z-score 2.15] and 14 BMI-matched controls (median age 11.97 years, BMI Z-score 2.34).
Despite comparable BMI Z-scores and leptin levels, the PWS children exhibited lower fasting insulin and HOMA-IR (homeostasis model assessment of insulin resistance) scores compared to obese controls. For any given BMI Z-score, the PWS children showed higher concentrations of fasting total and HMW adiponectin and higher HMW/total adiponectin ratios. The HMW/total adioponectin ratio was preserved in children with PWS at high degrees of obesity. In PWS children, fasting plasma total adiponectin, HMW adiponectin and HMW/total adiponectin ratio correlated negatively with age (P < 0.05), HOMA-IR (P < 0.01), BMI Z-score (P < 0.05), insulin (P < 0.01) and leptin (P < 0.05). In addition to higher fasting ghrelin concentrations, the PWS children showed significantly higher fasting levels of total peptide YY (PYY) and gastric inhibitory polypeptide (GIP) compared to obese controls.
Relative to controls of similar age and BMI Z-score, the PWS children had significantly higher levels of total and HMW adiponectin, and increased ratios of HMW/total adiponectin. These findings may explain in part the heightened insulin sensitivity of PWS children relative to BMI-matched controls.
Results from the recent Dietary Approaches to Stop Hypertension (DASH)-Sodium trial provide the latest evidence concerning the effects of dietary patterns and sodium intake on blood pressure. Participants ate either the DASH diet (high in fruits, vegetables and low-fat dairy products, and reduced in saturated and total fat) or a typical US diet. Within each diet arm, participants ate higher, intermediate, and lower sodium levels, each for 30 days. The results indicated lower blood pressure with lower sodium intake for both diet groups. Although some critics would argue otherwise, these findings provide important new evidence for the value of the DASH diet and sodium reduction in controlling blood pressure.
blood pressure; Dietary Approaches to Stop Hypertension (DASH) trial; hypertension; salt; sodium
Changes in sex hormones with weight loss might have implications for breast cancer prevention but have not been examined extensively, particularly in African-American (AA) women.
We conducted a prospective study of 278 overweight/obese postmenopausal women (38% AA) not taking hormone therapy within the Weight Loss Maintenance Trial. All participants lost at least 4 kg after a 6-month weight-loss phase and attempted to maintain weight loss during the subsequent 12 months. We evaluated the percentage changes in estrone, estradiol, free estradiol, testosterone, free testosterone, androstenedione, dehydroepiandrosterone sulfate and sex hormone-binding globulin (SHBG) using generalized estimating equations.
In all study phases, AA women had higher levels of estrogen and testosterone concentrations, independent of adiposity. On average, participants lost 7.7 kg during the weight-loss phase, and concentrations of estrone (-5.7%, P = 0.006), estradiol (-9.9%, P <0.001), free estradiol (-13.4%, P <0.0001), and free testosterone (-9.9%, P <0.0001) decreased, while the SHBG concentration (16.2%, P <0.001) increased. Weight change did not significantly affect total testosterone or other androgen concentrations. Compared with non-AA women, AA women experienced less change in estrogens per kilogram of weight change (that is, per 1 kg weight loss: estrone, -0.6% vs. -1.2%, P-interaction = 0.10; estradiol, -1.1% vs. -1.9%, P-interaction = 0.04; SHBG, 0.9% vs. 1.6%, P-interaction = 0.006; free estradiol, -1.4% vs. -2.1%, P-interaction = 0.01).
To the best of our knowledge this is the first study to examine and compare the effects of intentional weight loss and maintenance on a panel of sex hormones in AA women and non-AA women. Although speculative, these data suggest hormonal differences may contribute to different racial patterns of breast cancer incidence and mortality and encourage further investigations to understand the long-term effects of weight loss on sex hormones in obese postmenopausal women.
Automated reporting of estimated glomerular filtration rate (eGFR) is a recent advance in laboratory information technology (IT) that generates a measure of kidney function with chemistry laboratory results to aid early detection of chronic kidney disease (CKD). Because accurate diagnosis of CKD is critical to optimal medical decision-making, several clinical practice guidelines have recommended the use of automated eGFR reporting. Since its introduction, automated eGFR reporting has not been uniformly implemented by U. S. laboratories despite the growing prevalence of CKD. CKD is highly prevalent within the Veterans Health Administration (VHA), and implementation of automated eGFR reporting within this integrated healthcare system has the potential to improve care. In July 2004, the VHA adopted automated eGFR reporting through a system-wide mandate for software implementation by individual VHA laboratories. This study examines the timing of software implementation by individual VHA laboratories and factors associated with implementation.
We performed a retrospective observational study of laboratories in VHA facilities from July 2004 to September 2009. Using laboratory data, we identified the status of implementation of automated eGFR reporting for each facility and the time to actual implementation from the date the VHA adopted its policy for automated eGFR reporting. Using survey and administrative data, we assessed facility organizational characteristics associated with implementation of automated eGFR reporting via bivariate analyses.
Of 104 VHA laboratories, 88% implemented automated eGFR reporting in existing laboratory IT systems by the end of the study period. Time to initial implementation ranged from 0.2 to 4.0 years with a median of 1.8 years. All VHA facilities with on-site dialysis units implemented the eGFR software (52%, p<0.001). Other organizational characteristics were not statistically significant.
The VHA did not have uniform implementation of automated eGFR reporting across its facilities. Facility-level organizational characteristics were not associated with implementation, and this suggests that decisions for implementation of this software are not related to facility-level quality improvement measures. Additional studies on implementation of laboratory IT, such as automated eGFR reporting, could identify factors that are related to more timely implementation and lead to better healthcare delivery.
Traditionally, weight management behavioral research has focused on individual-level influences, with little attention given to interpersonal factors that relate to the family behavioral context.
This research examines the association between baseline family functioning scores and weight loss success in a sample of African Americans and Whites enrolled in a 20-week weight loss program with a weight loss goal of ≥4 kg.
Baseline surveys measuring six family functioning constructs were completed by 291 participants in a trial of weight loss maintenance. Analysis was limited to 217 participants in households with at least one other family member, and providing final weight measurements. We evaluated associations of family functioning, family composition, and demographic variables with weight loss success defined as losing ≥5% of initial body weight. Baseline predictors of weight loss success were determined using logistic regression analysis.
Participants were on average 61 years of age with BMI of 34 kg/m2; 57% were female and 75% self-identified as African American. Sixty-two percent lost at least 5% of initial body weight. In bivariate analysis, weight loss success was associated with higher income and education (p<0.01 and p=0.05, respectively), ethnicity (p<0.01), and the presence of a spouse (p=0.01). After adjusting for socio-demographic covariates in a multivariable model, the odds of weight loss success were independently influenced by a significant interaction between ethnicity and family cohesion (p<0.01).
These findings suggest that family context factors influence weight loss behaviors.
Weight loss; Family functioning; African American; Family cohesion; Behavioral intervention
The Weight Loss Maintenance Trial (WLM) compared two long-term weight-maintenance interventions, a personal contact arm and an Internet arm, with a no-treatment control after an initial six-month Phase I weight loss program. The Internet arm focused on use of an interactive website for support of long-term weight maintenance. There is limited information about patterns of website use and specific components of an interactive website that might help promote maintenance of weight loss.
This paper presents a secondary analysis of the subset of participants in the Internet arm and focuses on website use patterns and features associated with long-term weight maintenance.
Adults at risk for cardiovascular disease (CVD) who lost at least 4 kilograms in an initial 20-week group-based, behavioral weight-loss program were trained to use an interactive website for weight loss maintenance. Of the 348 participants, 37% were male and 38% were African American. Mean weight loss was 8.6 kilograms. Participants were encouraged to log in at least weekly and enter a current weight for the 30-month study period. The website contained features that encouraged setting short-term goals, creating action plans, and reinforcing self-management habits. The website also included motivational modules, daily tips, and tailored messages. Based on log-in and weight-entry frequency, we divided participants into three website use categories: consistent, some, and minimal.
Participants in the consistent user group (n = 212) were more likely to be older (P = .002), other than African American (P = .02), and more educated (P = .01). While there was no significant difference between website use categories in the amount of Phase I change in body weight (P = .45) or income (P = .78), minimal website users (n = 75) were significantly more likely to have attended fewer Phase I sessions (P = .001) and had a higher initial body mass index (BMI) (P < .001). After adjusting for baseline characteristics including initial BMI, variables most associated with less weight regain included: number of log-ins (P = .001), minutes on the website (P < .001), number of weight entries (P = .002), number of exercise entries (P < .001), and sessions with additional use of website features after weight entry (P = .002).
Participants defined as consistent website users of an interactive behavioral website designed to promote maintenance of weight loss were more successful at maintaining long-term weight loss.
NCT00054925; http://clinicaltrials.gov/ct2/show/NCT00054925 (Archived by WebCite at http://www.webcitation.org/5rC7523ue)
Weight maintenance; Internet; intervention; weight loss; behavioral strategies
The Study of the Effects of Diet on Metabolism and Nutrition (STEDMAN) Project uses comprehensive metabolic profiling to probe biochemical mechanisms of weight loss in humans. Measurements at baseline, 2 and 4 weeks, 6 and 12 months included diet, body composition, metabolic rate, hormones, and 80 intermediary metabolites measured by mass spectrometry. In 27 obese adults in a behavioral weight loss intervention, median weight decreased 13.9 lb over the first 6 months, then reverted towards baseline by 12 months. Insulin resistance (HOMA) was partially ameliorated in the first 6 months and showed sustained improvement at 12 months despite weight regain. Ghrelin increased with weight loss and reverted to baseline, whereas leptin and PYY fell at 6 months and remained persistently low. NPY levels did not change. Factors possibly contributing to sustained improvement in insulin sensitivity despite weight regain include adiponectin (increased by 12 months), IGF-1 (increased during weight loss and continued to increase during weight regain), and visceral fat (fell at 6 months but did not change thereafter). We observed a persistent reduction in free fatty acids, branched chain amino acids, and related metabolites that may contribute to improved insulin action. These findings provide evidence for sustained benefits of weight loss in obese humans and insights into mechanisms.
To improve methods for long-term weight management, the Weight Loss Maintenance (WLM) trial, a four-center randomized trial, was conducted to compare alternative strategies for maintaining weight loss over a 30-month period. This paper describes methods and results for the initial 6-month weight-loss program (Phase I).
Eligible adults were aged ≥25, overweight or obese (BMI=25–45 kg/m2), and on medications for hypertension and/or dyslipidemia. Anthropomorphic, demographic, and psychosocial measures were collected at baseline and 6 months. Participants (n=1685) attended 20 weekly group sessions to encourage calorie restriction, moderate-intensity physical activity, and the DASH (dietary approaches to stop hypertension) dietary pattern. Weight-loss predictors with missing data were replaced by multiple imputation.
Participants were 44% African American and 67% women; 79% were obese (BMI≥30), 87% were taking anti-hypertensive medications, and 38% were taking antidyslipidemia medications. Participants attended an average of 72% of 20 group sessions. They self-reported 117 minutes of moderate-intensity physical activity per week, kept 3.7 daily food records per week, and consumed 2.9 servings of fruits and vegetables per day. The Phase-I follow-up rate was 92%. Mean (SD) weight change was −5.8 kg (4.4), and 69% lost at least 4 kg. All race–gender subgroups lost substantial weight: African-American men (−5.4 kg ± 7.7); African-American women (−4.1 kg ± 2.9); non–African-American men (−8.5 kg ± 12.9); and non–African-American women (−5.8 kg ± 6.1). Behavioral measures (e.g., diet records and physical activity) accounted for most of the weight-loss variation, although the association between behavioral measures and weight loss differed by race and gender groups.
The WLM behavioral intervention successfully achieved clinically significant short-term weight loss in a diverse population of high-risk patients.