Predictors of racial differences in weight loss: the PROPEL trial

OBJECTIVE

Studies have consistently shown that African American individuals lose less weight in response to behavioral interventions, but the mechanisms leading to this result have been understudied.

METHODS

Data were derived from the PROmoting Successful Weight Loss in Primary CarE in Louisiana (PROPEL) study, which was a cluster-randomized, two-arm trial conducted in primary care clinics. In the PROPEL trial, African American individuals lost less weight compared with patients who belonged to other racial groups after 24 months. In the current study, counterfactual mediation analyses among 445 patients in the intervention arm of PROPEL were used to determine which variables mediated the relationship between race and weight loss. The mediators included treatment engagement, psychosocial, and lifestyle factors.

RESULTS

At 6 months, daily weighing mediated 33% (p = 0.008) of the racial differences in weight loss. At 24 months, session attendance and daily weighing mediated 35% (p = 0.027) and 66% (p = 0.005) of the racial differences in weight loss, respectively. None of the psychosocial or lifestyle variables mediated the race-weight loss association.

CONCLUSIONS

Strategies specifically targeting engagement, such as improving session attendance and self-weighing behaviors, among African American individuals are needed to support more equitable weight losses over extended time periods.

Longitudinal Profiling of Fasting Plasma Metabolome in Response to Weight-Loss Interventions in Patients with Morbid Obesity

It is well recognized that patients with severe obesity exhibit remarkable heterogeneity in response to different types of weight-loss interventions. Those who undergo Roux-en-Y gastric bypass (RYGB) usually exhibit more favorable glycemic outcomes than those who receive adjustable gastric banding (BAND) or intensive medical intervention (IMI). The molecular mechanisms behind these observations, however, remain largely unknown. To identify the plasma metabolites associated with differential glycemic outcomes induced by weight-loss intervention, we studied 75 patients with severe obesity (25 each in RYGB, BAND, or IMI). Using untargeted metabolomics, we repeatedly measured 364 metabolites in plasma samples at baseline and 1-year after intervention. Linear regression was used to examine whether baseline metabolites or changes in metabolites are associated with differential glycemic outcomes in response to different types of weight-loss intervention, adjusting for sex, baseline age, and BMI as well as weight loss. Network analyses were performed to identify differential metabolic pathways involved in the observed associations. After correction for multiple testing (q < 0.05), 33 (RYGB vs. IMI) and 28 (RYGB vs. BAND) baseline metabolites were associated with changes in fasting plasma glucose (FPG) or glycated hemoglobin (HbA1c). Longitudinal changes in 38 (RYGB vs. IMI) and 38 metabolites (RYGB vs. BAND) were significantly associated with changes in FPG or HbA1c. The identified metabolites are enriched in pathways involved in the biosynthesis of aminoacyl-tRNA and branched-chain amino acids. Weight-loss intervention evokes extensive changes in plasma metabolites, and the altered metabolome may underlie the differential glycemic outcomes in response to different types of weight-loss intervention, independent of weight loss itself.

DNA methylation is differentially associated with glycemic outcomes by different types of weight-loss interventions: an epigenome-wide association study

BACKGROUND

Alterations in DNA methylation (DNAm) have been reported to be a mechanism by which bariatric surgeries resulted in considerable metabolic improvements. Previous studies have mostly focused on change in DNAm following weight-loss interventions, yet whether DNAm prior to intervention can explain the variability in glycemic outcomes has not been investigated. Here, we aim to examine whether baseline DNAm is differentially associated with glycemic outcomes induced by different types of weight-loss interventions.

METHODS

Participants were 75 adults with severe obesity who underwent non-surgical intensive medical intervention (IMI), adjustable gastric band (BAND) or Roux-en-Y gastric bypass (RYGB) (n = 25 each). Changes in fasting plasma glucose (FPG) and glycated hemoglobin (HbA1c) were measured at 1-year after intervention. DNAm was quantified by Illumina 450 K arrays in baseline peripheral blood DNA. Epigenome-wide association studies were performed to identify CpG probes that modify the effects of different weight-loss interventions on glycemic outcomes, i.e., changes in FPG and HbA1c, by including an interaction term between types of intervention and DNAm. Models were adjusted for weight loss and baseline clinical factors.

RESULTS

Baseline DNAm levels at 3216 and 117 CpGs were differentially associated with changes in FPG and HbA1c, respectively, when comparing RYGB versus IMI. Of these, 79 CpGs were significant for both FPG and HbA1c. The identified genes are enriched in adaptive thermogenesis, temperature homeostasis and regulation of cell population proliferation. Additionally, DNAm at 6 CpGs was differentially associated with changes in HbA1c when comparing RYGB versus BAND.

CONCLUSIONS

Baseline DNAm is differentially associated with glycemic outcomes in response to different types of weight-loss interventions, independent of weight loss and other clinical factors. Such findings provided initial evidence that baseline DNAm levels may serve as potential biomarkers predictive of differential glycemic outcomes in response to different types of weight-loss interventions.

Weight Loss in Underserved Patients - A Cluster-Randomized Trial

BACKGROUND

Evidence of the effectiveness of treatment for obesity delivered in primary care settings in underserved populations is lacking.

METHODS

We conducted a cluster-randomized trial to test the effectiveness of a high-intensity, lifestyle-based program for obesity treatment delivered in primary care clinics in which a high percentage of the patients were from low-income populations. We randomly assigned 18 clinics to provide patients with either an intensive lifestyle intervention, which focused on reduced caloric intake and increased physical activity, or usual care. Patients in the intensive-lifestyle group participated in a high-intensity program delivered by health coaches embedded in the clinics. The program consisted of weekly sessions for the first 6 months, followed by monthly sessions for the remaining 18 months. Patients in the usual-care group received standard care from their primary care team. The primary outcome was the percent change from baseline in body weight at 24 months.

RESULTS

All 18 clinics (9 assigned to the intensive program and 9 assigned to usual care) completed 24 months of participation; a median of 40.5 patients were enrolled at each clinic. A total of 803 adults with obesity were enrolled: 452 were assigned to the intensive-lifestyle group, and 351 were assigned to the usual-care group; 67.2% of the patients were Black, and 65.5% had an annual household income of less than $40,000. Of the enrolled patients, 83.4% completed the 24-month trial. The percent weight loss at 24 months was significantly greater in the intensive-lifestyle group (change in body weight, -4.99%; 95% confidence interval [CI], -6.02 to -3.96) than in the usual-care group (-0.48%; 95% CI, -1.57 to 0.61), with a mean between-group difference of -4.51 percentage points (95% CI, -5.93 to -3.10) (P<0.001). There were no significant between-group differences in serious adverse events.

CONCLUSIONS

A high-intensity, lifestyle-based treatment program for obesity delivered in an underserved primary care population resulted in clinically significant weight loss at 24 months. (Funded by the Patient-Centered Outcomes Research Institute and others; PROPEL ClinicalTrials.gov number, NCT02561221.).

HEADS UP: Design and Methods of a Louisiana State-Funded Surgical and Non-Surgical Weight Loss Program

This paper describes the methodology, design and procedures used in the HEADS UP Project, an observational study to examine the feasibility of a state-funded weight loss program. HEADS UP offered two weight loss approaches: bariatric surgery or a non-surgical intervention composed of medical management, a low-calorie liquid diet and lifestyle change promotion. Participants were recruited through a multi-stage screening process, in-person interviews, and an initial low-calorie diet program. Eligible participants were entered into a lottery system, with 100 participants selected for the surgical group and 200 selected for the non-surgical group annually for five years. Anthropometric, clinical, and psychosocial assessments were completed at baseline and follow-ups. More than 6800 individuals completed the initial web screening. Screening procedures yielded 1412 participants (490 surgical and 922 non-surgical). Approximately 84% of the total participant population were female and 38% were Black. Participants had an average body mass index of 47.9 and 43 kg/m² in the surgical and non-surgical groups, respectively. Recruitment and enrollment results of the HEADS UP study demonstrated significant interest in both the surgical and non-surgical treatment programs for obesity. These results support the feasibility of providing a state-funded weight loss program within a healthcare setting.

Promoting Successful Weight Loss in Primary Care in Louisiana (PROPEL): Rationale, design and baseline characteristics

Underserved and minority populations suffer from a disproportionately high prevalence of obesity and related comorbidities. Effective obesity treatment programs delivered in primary care that produce significant weight loss are currently lacking. The purpose of this trial is to test the effectiveness of a pragmatic, high intensity lifestyle-based obesity treatment program delivered within primary care among an underserved population. We hypothesize that, relative to patients who receive usual care, patients who receive a high-intensity, health literacy- and culturally-appropriate lifestyle intervention will have greater percent reductions in body weight over 24 months. Eighteen clinics (N = 803 patients) serving low income populations with a high proportion of African Americans in Louisiana were randomized to the intervention or usual car. Patients in the intervention participate in a high-intensity lifestyle program delivered by health coaches employed by an academic health center and embedded in the primary care clinics. The program consists of weekly (16 in-person/6 telephone) sessions in the first six months, followed by sessions held at least monthly for the remaining 18 months. Primary care practitioners in usual care receive information on weight management and the current Centers for Medicare and Medicaid Services reimbursement for obesity treatment. The primary outcome is percent weight loss at 24 months. Secondary outcomes include absolute 24-month changes in body weight, waist circumference, blood pressure, fasting glucose and lipids, health-related quality of life, and weight-related quality of life. The results will provide evidence on the effectiveness of implementing high-intensity lifestyle and obesity counseling in primary care settings among underserved populations.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT02561221.

Family PArtners in Lifestyle Support (PALS): Family-based weight loss for African American adults with type 2 diabetes

OBJECTIVE

To develop and test a family-centered behavioral weight loss intervention for African American adults with type 2 diabetes.

METHODS

In this randomized trial, dyads consisting of an African American adult with overweight or obesity and type 2 diabetes (index participant) paired with a family partner with overweight or obesity but not diagnosed with diabetes were assigned in a 2:1 ratio to a 20-week special intervention (SI) or delayed intervention (DI) control group. The primary outcome was weight loss among index participants at the 20-week follow-up.

RESULTS

One hundred eight participants (54 dyads-36 (SI) and 18 (DI) dyads) were enrolled: 81% females; mean age, 51 years; mean weight,103 kg; and mean BMI, 37 kg/m² . At post-intervention, 96 participants (89%) returned for follow-up measures. Among index participants, mean difference in weight loss between groups was -5.0 kg, P <0.0001 (-3.6 kg loss among SI; 1.4 kg gain in DI). SI index participants showed significantly greater improvements in hemoglobin A1c, depressive symptoms, family interactions, and dietary, physical activity, and diabetes self-care behaviors. SI family partners also had significant weight loss (-3.9 kg (SI) vs. -1.0 kg (DI), P = 0.02).

CONCLUSIONS

A family-centered, behavioral weight loss intervention led to clinically significant short-term weight loss among family dyads.

The Ways of Religious Coping Scale: Reliability, Validity, and Scale Development

Ample evidence suggests stress can have serious effects on both physical and mental health. This has motivated researchers to investigate which coping strategies lead to more adaptive responses. One such strategy receiving an increasing amount of attention is religious coping. However, the measurement of religious coping needs further development. The present study reports the development and preliminary reliability and validity studies of the Ways of Religious Coping Scale (WORCS). This scale is a self-report instrument for assessing the degree and kind of religious cognitions and behaviors people use to cope with stress. Results indicate the WORCS is psychometrically sound and may be a useful tool for future research in the area of religious coping.

Predicting Medical Regimen Adherence: The Interactions of Health Locus of Control Beliefs

The present study examined the interactions between five dimensions of health locus of control beliefs and their relationships with medical regimen adherence in low-income individuals diagnosed with type 2 diabetes. One hundred and nine patients were administered an expanded Multidimensional Health Locus of Control (MHLC) scale. HbA1c was used as a biological indicator of medical regimen adherence. Multivariate regression analyses demonstrated that three interactions were significantly related to HbA1c. The present findings suggest that HLOC may be meaningfully related to medical outcomes. However, these relationships may not be captured through the examination of main effects and may be only found when interactions are considered.

The impact of continued intervention on weight: Five-year results from the weight loss maintenance trial

OBJECTIVE

In the Weight Loss Maintenance (WLM) Trial, a personal contact (PC) intervention sustained greater weight loss relative to a self-directed (SD) group over 30 months. This study investigated the effects of continued intervention over an additional 30 months and overall weight change across the entire WLM Trial.

METHODS

WLM had 3 phases. Phase 1 was a 6-month weight loss program. In Phase 2, those who lost ≥4 kg were randomized to a 30-month maintenance trial. In Phase 3, PC participants (n = 196, three sites) were re-randomized to no further intervention (PC-Control) or continued intervention (PC-Active) for 30 more months; 218 SD participants were also followed.

RESULTS

During Phase 3, weight increased 1.0 kg in PC-Active and 0.5 kg in PC-Control (mean difference 0.6 kg; 95% CI:-1.4 to 2.7; P = 0.54). Mean weight change over the entire study was -3.2 kg in those originally assigned to PC (PC-Combined) and -1.6 kg in SD (mean difference -1.6 kg; 95% CI:-3.0 to -0.1; P = 0.04).

CONCLUSIONS

After 30 months of the PC maintenance intervention, continuation for another 30 months provided no additional benefit. However, across the entire study, weight loss was slightly greater in those originally assigned to PC.

Psychosocial predictors of weight loss by race and sex

This paper examined the psychosocial predictors of weight loss among race and sex subgroups. Analyses included overweight and obese participants from the PREMIER study, a previously published randomized trial that examined the effects of two multi-component lifestyle interventions on blood pressure among pre-hypertensive and stage 1 hypertensive adults. Both intervention conditions received behavioural recommendations for weight loss and group sessions. Weight and psychosocial measures of self-efficacy and social support for diet and exercise were assessed at baseline and at 6 months. There were 157 African-American (AA) women, 46 AA men, 203 non-AA women and 182 non-AA men with an average age of 50 years and average body mass index of 34 at baseline. Multiple predictor regression models were performed individually by race and sex subgroup. Among AA women, increases in diet self-efficacy were associated with weight loss. Among AA men, increases in diet-related social support and self-efficacy, along with increases in family support to exercise, were associated with weight loss (all Ps <0.05). Among non-AA women, increases in friends' support to exercise and exercise-related self-efficacy were associated with weight loss, and among non-AA men only increases in diet self-efficacy were associated with weight loss (all Ps <0.05). These results emphasize the need for targeted interventions based on race and sex to optimize the impact of lifestyle-based weight loss programmes.

Why patients seek bariatric surgery: does insurance coverage matter?

Despite increasing prevalence of bariatric surgery, little is known about why patients seek out this treatment option. Heads Up is an observational study sponsored by a large benefits management group that examines surgical and nonsurgical approaches to weight management in obese adults. This study examined patients' reasons for choosing surgery. The sample included 360 adult obese patients seeking bariatric surgery who were invited to volunteer for a surgical or a medical weight loss program by their insurer. Participants rank ordered their top three reasons as a deciding factor for choosing to consider surgery. The top three reasons were concerns regarding health (52%), current obesity-related medical conditions (28%), and improved physical fitness (5%). Overall, 13% endorsed insurance coverage as one of their top three choices. When insurance coverage is assured, health and functionality issues were the major reasons reported for obese adults choosing to undergo bariatric surgery.

Application of Latent Class Analysis to Identify Behavioral Patterns of Response to Behavioral Lifestyle Interventions in Overweight and Obese Adults

BACKGROUND

Examining responders and non-responders to behavioral lifestyle interventions among overweight/obese adults with additional comorbidities may aid in refining and tailoring obesity treatment.

PURPOSE

The purpose of this study is to demonstrate the use of latent class analysis to identify patterns of response to behavioral lifestyle interventions based on adherence to diet and exercise recommendations.

METHOD

Repeated measures latent class analysis was applied to two clinical trial datasets, combination of two active interventions in the PREMIER Trial (n = 501) and phase 1 of the Weight Loss Maintenance Trial (WLM; n = 1685), to identify patterns of response to behavioral lifestyle interventions. Treatment response was based on adherence to daily recommendations for fruit/vegetable, fat, saturated fat, sodium, and exercise at baseline and 6 months.

RESULTS

In PREMIER, three distinct latent classes emerged: responders (45.9%), non-responders (23.6%), and early adherers (30.5%). Responders and Early Adherers had greater weight loss at 6 and 18 months and were more likely to meet behavioral recommendations at 18 months than Non-responders. For WLM, there were four latent classes: partial responders (16%), non-responders (40%), early adherers (2%), and fruit/veggie only responders (41%). Non-responders in WLM had significantly less weight loss at 6 months compared to that of the other three latent classes.

CONCLUSION

Latent class analysis is a useful method to apply to clinical trial data to identify distinct patterns of response to behavioral interventions. Overweight/ obese participants who respond to behavioral lifestyle treatment (i.e., meet behavioral recommendations) have significantly greater weight loss than that of participants who do not make behavioral changes.

Predictors for selection of insurance-funded weight loss approaches in individuals with severe obesity

OBJECTIVE

To determine whether there are differences in baseline psychological and behavioral characteristics between individuals with severe obesity who chose a surgical or nonsurgical intervention for weight loss.

METHODS

The current study utilized data from a larger study funded by a state insurance company and is unique in that the insurance company funded the weight loss interventions. Participants indicated their preferred method of weight loss, and completed several self-report psychological questionnaires, as well as demographic information.

RESULTS

Participants (N = 605) were 58.8% Caucasian and mostly (86%) female. Logistic regression results indicated that an increased number of weight loss attempts, and select other measures of eating behavior and quality of life may influence individuals' selection for either surgical or nonsurgical treatments for weight loss.

CONCLUSIONS

Practitioners should pay particular attention to these baseline characteristics that influence choice to examine potential characteristics that may influence the success of these weight loss treatments.

Predictors of dietary change among those who successfully lost weight in phase I of the Weight Loss Maintenance Trial

AIM

Dietary changes occurring during weight loss interventions can vary. The present study tested if pretreatment psychosocial, dietary and demographic factors were associated with changes in fat intake and fruit and vegetable intake during a weight loss intervention.

METHODS

This analysis includes participants who lost at least four kilograms during the initial six month weight loss phase (phase I) of the Weight Loss Maintenance Trial, a group format behavioural intervention emphasising a low-fat diet and increased physical activity. Multiple linear regression was used to determine associations between pretreatment psychosocial, dietary, physical activity, and demographic variables and changes from pretreatment to six months in fat intake and fruit and vegetable intake.

RESULTS

Participants (n = 1032) were 63.4% female, 62.4% non-African American, and had a mean age of 55.6 and BMI of 34.1 kg/m². Being African American (P < 0.0001) and higher baseline kilojoule intake (P < 0.01) were associated with smaller reductions in fat intake. Being African American (p < 0.001) and older age (P = 0.02) were associated with smaller increases in fruit and vegetable intake, whereas a history of 10 or more past weight loss episodes of at least 10 lb (4.5 kg; P < 0.01) was associated with greater increases.

CONCLUSIONS

Few psychosocial factors examined contributed to variability in dietary change. Even when achieving meaningful weight losses during a behavioural weight loss intervention, African Americans may make fewer beneficial changes in fat and fruit and vegetable intake than non-African Americans.

Five-Year Medical and Pharmacy Costs after a Medically Supervised Intensive Treatment Program for Obesity

Purpose.

The financial impact of intensive medical interventions for weight loss has not been fully studied.

Design.

A randomized pragmatic clinical trial.

Setting.

Seven primary care clinics and one research center in Louisiana.

Subjects.

Severely obese individuals (body mass index 40–60 kg/m2) randomized to usual care (n = 190) or intensive medical management (n = 200). Forty-seven percent of participants completed year 2 follow-up and were included in the analyses.

Intervention.

Physician-monitored intervention with recommendations for 12 weeks of liquid diet followed by 4 months of group behavioral therapy, structured diet, and option of pharmacotherapy, and an additional 16 months of maintenance strategies. Measures. Two-year preintervention and 5-year postintervention measures were computed from claims data and included (1) medical costs excluding pharmacy, (2) pharmacy costs only, (3) total medical and pharmacy costs, and (4) medical and pharmacy subcategory costs.

Analysis.

Differential categories for preintervention and postintervention were created using total sample 75th percentiles. Chi-square tests were employed to compare the intervention groups both preintervention and postintervention with respect to the proportion of subjects above the 75th percentile for each of the cost categories.

Results.

Medical costs excluding pharmacy did not differ between groups. The intensive medical intervention group had a significantly smaller percentage of subjects above the 75th percentile for pharmacy costs only (p = .0125), and for antidiabetic agents (p = .0464), antihypertensives (p = .0075), and dyslipidemic subcategories (p = .0197).

Conclusion.

An intensive medical intervention may reduce pharmaceutical expenditures in severely obese individuals. These results must be viewed with caution given the high attrition of study participants.

Psychosocial predictors of weight regain in the weight loss maintenance trial

This study's purpose was to identify psychosocial predictors of weight loss maintenance in a multi-site clinical trial, following a group-based weight loss program. Participants (N = 1025) were predominately women (63%) and 38% were Black (mean age = 55.6 years; SD = 8.7). At 12 months, higher SF-36 mental health composite scores were associated with less weight regain (p < .01). For Black participants, an interaction existed between race and friends' encouragement for exercise, where higher exercise encouragement was related to more weight regain (p < .05). At 30 months, friends' encouragement for healthy eating was associated with more weight regain (p < .05), whereas higher SF-36 mental health composite scores were related to less weight regain (p < .0001). Perceived stress and select health-related quality of life indices were associated with weight regain; this relationship varied across gender, race, and treatment conditions. Temporal changes in these variables should be investigated for their impact on weight maintenance.

Examining behavioral processes through which lifestyle interventions promote weight loss: results from PREMIER

OBJECTIVE

To examine the behavioral processes through which lifestyle interventions impacted weight loss.

METHODS

The analyses were limited to overweight and obese Black and White adults randomized to a PREMIER lifestyle intervention (N = 501). Structural equation modeling was conducted to test the direct and indirect relationships of session attendance, days of self-monitoring diet and exercise, change in diet composition and exercise, and 6-month weight change.

RESULTS

Greater session attendance was associated with increased self-monitoring, which was in turn significantly related to reduction in percent energy from total fat consumed. Change in percent energy from fat and self-monitoring was associated with 6-month percent change in weight. Both a decrease in fat intake and increase in self-monitoring are potential mediators of the relationship between attendance and weight change.

CONCLUSIONS

The findings provide a reasonable model that suggests regular session attendance and use of behavioral strategies like self-monitoring are associated with improved behavioral outcomes that are associated with weight loss.

Greater weight loss with increasing age in the weight loss maintenance trial

OBJECTIVE

To determine the effect of age on weight loss and weight loss maintenance in participants in the Weight Loss Maintenance trial (WLM).

DESIGN AND METHODS

Secondary analysis of a randomized controlled trial of overweight/obese adults with CVD risk factors was conducted. Participants were 1685 adults with baseline BMI 25-45 kg m(2) with hypertension and/or dyslipidemia. Those who lost at least 4kg in an initial 6-month behavioral weight loss intervention (N = 1,032) were randomly assigned to a 30-month maintenance phase of self-directed control (SD), monthly personal counseling (PC), or unlimited access to an internet-based intervention (IT). Age groups were defined post-hoc and weight change was compared among age groups.

RESULTS

Participants ≥60 years old initially lost more weight than younger individuals, and sustained greater weight loss in IT and PC but not in SD (P value for trend 0.024, 0.002, and 0.36, respectively).

CONCLUSIONS

In WLM, adults age ≥60 years had greater initial weight loss and greater sustained weight loss over 3 years, compared to younger adults. Older adults had greater weight loss maintenance with either personal counseling or internet-based intervention. Future research should determine optimal implementation strategies and effects of weight loss on health outcomes in older adults.

Impact of 5-year weight change on blood pressure: results from the Weight Loss Maintenance trial

In this secondary analysis of the Weight Loss Maintenance trial, the authors assessed the relationship between blood pressure (BP) change and weight change in overweight and obese adults with hypertension and/or dyslipidemia who were randomized to 1 of 3 weight loss maintenance strategies for 5 years. The participants were grouped (N=741) based on weight change from randomization to 60 months as: (1) weight loss, (2) weight stable, or (3) weight gain. A significant positive correlation between weight change and systolic BP (SBP) change at 12, 30, and 60 months and between weight change and diastolic BP (DBP) change at 30 months was observed. From randomization to 60 months, mean SBP increased to a similar degree for the weight gain group (4.2±standard error=0.6 mm Hg; P<.001) and weight stable group (4.6±1.1 mm Hg; P<.001), but SBP did not rise in the weight loss group (1.0±1.7 mm Hg, P=.53). DBP was unchanged for all groups at 60 months. Although aging may have contributed to rise in BP at 60 months, it does not appear to fully account for observed BP changes. These results suggest that continued modest weight loss may be sufficient for long-term BP lowering.

Self-Efficacy as a Predictor of Weight Change in African-American Women

OBJECTIVE

Although self-efficacy has received increasing attention for its role in weight loss, there is less research examining this relationship in minority samples. The purpose of this study was to determine whether self-efficacy for weight loss was predictive of weight change in a sample of African-American women.

RESEARCH METHODS AND PROCEDURES

Subjects were 106 overweight or obese, low-income African-American women participating in a weight management intervention that involved either personalized monthly sessions with their primary care physician or standard care. Weight and self-efficacy for weight loss were assessed at baseline and at the end of the 6-month treatment.

RESULTS

For subjects in the personalized intervention, baseline self-efficacy was predictive of subsequent weight change, such that higher levels of self-efficacy before treatment were associated with less weight loss. In contrast, improvements in self-efficacy during treatment were associated with greater weight loss for the personalized intervention group.

DISCUSSION

Results suggest high self-efficacy for weight loss before treatment may be detrimental to success, whereas treatments that improve participants' self-efficacy may result in greater weight loss. High pretreatment self-efficacy may be indicative of overconfidence or lack of experience with the difficulties associated with weight loss efforts. Whereas replication is needed, our results suggest that self-efficacy is an important variable to consider when implementing weight loss interventions.

Predictors of long-term weight loss in adults with modest initial weight loss, by sex and race

Effective weight management interventions could reduce race-sex disparities in cardiovascular disease (CVD), yet little is known about factors associated with successful weight loss maintenance in race-sex subgroups. In the Weight Loss Maintenance trial (WLM), overweight/obese (BMI 25-45 kg/m(2)) adults who lost ≥4 kg in a 6-month behavioral weight loss intervention (phase I) were randomized into one of three 30-month maintenance interventions (phase II). To investigate predictors in subgroups, randomized groups were combined for this analysis. Of 1,685 phase I participants, 1,032 (61%) entered phase II, including 12% black men (BM), 26% black women (BW), 25% white men (WM), and 37% white women (WW). Weight change over the 36-month study ranged from -2.3% (95% confidence interval = -3.1 to -1.5%) in BW to -4.5% (95% confidence interval = -5.7 to -4.0%) in WM, the result of differential weight loss during phase I. Within race, men lost significantly more weight than women, but within sex group, weight loss did not differ significantly between races. Although participants regained weight during phase II, regain did not differ by race-sex group, and mean weight at the end of the study was significantly lower than phase I entry weight for each subgroup. In regression models, phase I weight loss predicted overall 36-month weight loss in all race-sex groups. Healthy dietary pattern at entry, improvement in dietary pattern, or both were predictive in three of four race-sex groups. Few other variables other than initial weight loss and dietary pattern were predictive. Future research should identify additional modifiable influences on long-term maintenance after a modest weight loss.

Branched-chain amino acid levels are associated with improvement in insulin resistance with weight loss

AIMS/HYPOTHESIS

Insulin resistance (IR) improves with weight loss, but this response is heterogeneous. We hypothesised that metabolomic profiling would identify biomarkers predicting changes in IR with weight loss.

METHODS

Targeted mass spectrometry-based profiling of 60 metabolites, plus biochemical assays of NEFA, β-hydroxybutyrate, ketones, insulin and glucose were performed in baseline and 6 month plasma samples from 500 participants who had lost ≥4 kg during Phase I of the Weight Loss Maintenance (WLM) trial. Homeostatic model assessment of insulin resistance (HOMA-IR) and change in HOMA-IR with weight loss (∆HOMA-IR) were calculated. Principal components analysis (PCA) and mixed models adjusted for race, sex, baseline weight, and amount of weight loss were used; findings were validated in an independent cohort of patients (n = 22).

RESULTS

Mean weight loss was 8.67 ± 4.28 kg; mean ∆HOMA-IR was -0.80 ± 1.73, range -28.9 to 4.82). Baseline PCA-derived factor 3 (branched chain amino acids [BCAAs] and associated catabolites) correlated with baseline HOMA-IR (r = 0.50, p < 0.0001) and independently associated with ∆HOMA-IR (p < 0.0001). ∆HOMA-IR increased in a linear fashion with increasing baseline factor 3 quartiles. Amount of weight loss was only modestly correlated with ∆HOMA-IR (r = 0.24). These findings were validated in the independent cohort, with a factor composed of BCAAs and related metabolites predicting ∆HOMA-IR (p = 0.007).

CONCLUSIONS/INTERPRETATION

A cluster of metabolites comprising BCAAs and related analytes predicts improvement in HOMA-IR independent of the amount of weight lost. These results may help identify individuals most likely to benefit from moderate weight loss and elucidate novel mechanisms of IR in obesity.

Lifestyle factors and ghrelin: critical review and implications for weight loss maintenance

Ghrelin, the only known appetite-stimulating hormone in humans, may be one factor involved in increased appetite, cravings and food intake following weight loss. Innovative strategies for suppressing ghrelin and decreasing appetite during weight loss maintenance are needed. Recent research has highlighted relationships between ghrelin, stress and lifestyle factors. The purposes of the current review are to (i) describe the current status of knowledge about ghrelin and lifestyle factors; (ii) critically examine research in this area, highlighting inconsistencies and methodological issues and (iii) discuss future directions and implications for obesity treatment. Based on Literature search using PsycINFO and Medline databases, we reviewed experimental studies on relationships between ghrelin, stress, exercise and sleep. Ghrelin levels are positively related to stress hormones, and stress management interventions including exercise and sleep may help to reduce acylated ghrelin and corresponding appetite. Behavioural interventions may offer a practical, cost-effective alternative for reducing or stabilizing ghrelin levels after initial weight loss. Adding behavioural techniques designed to reduce ghrelin to traditional weight loss maintenance protocols may help individuals to maintain weight loss. Future directions for investigating relationships between ghrelin and behavioural factors, examining the efficacy of behavioural programmes in reducing ghrelin and improving weight loss maintenance are discussed.

Development and Implementation of a Tailored Self-assessment Tool in an Internet-based Weight Loss Maintenance Program

BACKGROUND

Using the Internet to replicate client/counselor interactions provides a tremendous opportunity to disseminate interventions at relatively low cost per participant. However, there are substantial challenges with this approach. The Weight Loss Maintenance Trial (WLM) compared two long-term weight-maintenance interventions: (1) a personal contact arm and (2) an Internet arm, to a third self-directed control arm. The Internet arm focused on use of an interactive website for support of long-term weight maintenance. This paper describes a highly interactive self-assessment tool developed for use in the WLM trial Internet intervention arm.

METHODS

The Tailored Self-Assessment (TSA) website tool was an interactive resource for those WLM participants assigned to the Internet arm to review their personal weight-management progress and make choices about future weight-management actions. The TSA was highly tailored and ended with a suggested list of personalized action plans. While the participant could complete the TSA at any time, criteria-based reminder messages prompted participation.

RESULTS

The TSA was one of 27 interactive tools on the WLM website. Over the course of the 28 months, the TSA was completed 800 times by the 348 randomized participants. Fifty-three percent of the participants (185/348) used the TSA at least once (range: 0, 110) and 72% of the 185 participants who did complete the TSA at least once, completed it more than once.

CONCLUSION

The Internet has great potential to impact health behavior by attempting to replicate personal counseling. We learned that while development is complex and appears costly, tailored strategies based on client feedback are likely worthwhile and should be formally tested.

Family functioning and weight loss in a sample of african americans and whites

BACKGROUND

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.

PURPOSE

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.

METHODS

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.

RESULTS

Participants were on average 61 years of age with BMI of 34 kg/m(2); 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).

CONCLUSIONS

These findings suggest that family context factors influence weight loss behaviors.

Effects of the PREMIER interventions on health-related quality of life

BACKGROUND

Health-related quality of life (HRQOL) is an important aspect of well-being that may improve with health behavior interventions. However, health behavior change is difficult with pressure to maintain status quo.

PURPOSE

This report examines the effects of two lifestyle interventions and an advice-only condition on HRQOL. Effects of meeting behavioral goals and weight loss also were examined.

METHODS

Participants were 295 men and 467 women (34% African American) with pre-hypertension or stage 1 hypertension from the PREMIER trial. HRQOL was assessed by the Short Form-36. Participants were assigned randomly to (1) advice only (ADVICE), (2) established guidelines for blood pressure control (EST), or (3) established guidelines plus the Dietary Approaches to Stop Hypertension (DASH) dietary pattern (EST + DASH).

RESULTS

Assignment to EST resulted in improvement in three HRQOL subscales at 6 months and one at 18 months relative to ADVICE. EST + DASH improved in two subscales at 6 and 18 months compared with ADVICE. Across conditions, total fat, saturated fat, fruit, and vegetable intake change, along with ≥ 4-kg weight loss, resulted in HRQOL improvements at 6 and 18 months. No improvement was found for change in physical activity, and only a few HRQOL subscales were associated with change in sodium and low-fat dairy intake.

CONCLUSIONS

Intensive lifestyle interventions can result in improvements in HRQOL. Change in dietary intake and weight loss is also important.

Associations of internet website use with weight change in a long-term weight loss maintenance program

Background

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.

Objective

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.

Methods

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.

Results

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).

Conclusion

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.

Trial Registration

NCT00054925; http://clinicaltrials.gov/ct2/show/NCT00054925 (Archived by WebCite at http://www.webcitation.org/5rC7523ue)

Dietary salt reduction in rural patients with albuminurea using family and community support: the Mima study

BACKGROUND

Residents of rural communities are often more socially connected compared to urban dwellers. Using family and community support to motivate health behavior change may be useful in rural settings. The objective of this study was to pilot a salt reduction (SR) intervention for rural albuminuria patients using support from family and neighborhood residents compared to a usual care condition. The primary outcome was change in urine albumin-creatinine ratio (ACR).

METHODS

All consecutive outpatients with an ACR >= 30 mg/gCr were recruited from the Koyadaira Clinic. Patients self-selected their participation in the intervention group (IG) or the control group (CG) because the rural population expressed concern about not being treated at the same time. In the IG, patients and their families were educated in SR for 30 minutes in their home by experienced dieticians. In addition, patients, families and neighborhood residents were also educated in SR for 2 hours at a public town meeting hall, with educational content encouraging reduction in salt intake through interactive activity. The CG received conventional treatment, and ACR and blood pressure (BP) were measured after 3 months.

RESULTS

Of the 37 subjects recruited (20 male, 16 female, mean age; 72.8 +/- 9.2 years), 36 completed the 3-month follow up and were analyzed. In the IG, ACR decreased significantly from baseline (706 +/- 1,081 to 440 +/- 656; t = 2.28, p = 0.04) and was reduced compared to the CG (213 +/- 323 to 164 +/- 162; F = 3.50, p = 0.07), a treatment effect approaching significance. Systolic BP in the IG (145 +/- 14 to 131 +/- 13 mmHg; t = 3.83, p = 0.002) also decreased significantly compared to the CG (135 +/- 13 to 131 +/- 14; F = 4.40, p = 0.04).

CONCLUSIONS

Simultaneous education of patients, their families and neighborhood residents may be important in rural areas for treatments and interventions requiring health behavior change.

TRIAL REGISTRATION

UMIN000001972.

Nonsurgical weight loss for extreme obesity in primary care settings: results of the Louisiana Obese Subjects Study

BACKGROUND

Effective primary care practice (PCP) treatments are needed for extreme obesity. The Louisiana Obese Subjects Study (LOSS) tested whether, with brief training, PCPs could effectively implement weight loss for individuals with a body mass index (BMI) (calculated as weight in kilograms divided by height in meters squared) of 40 to 60.

METHODS

The LOSS, a 2-year (July 5, 2005, through January 30, 2008) randomized, controlled, "pragmatic clinical trial" trained 7 PCPs and 1 research clinic in obesity management. Primary outcome measure was year-2 percentage change from baseline weight. Volunteers (597) were screened and randomized to intensive medical intervention (IMI) (n = 200) or usual care condition (UCC) (n = 190). The UCC group had instruction in an Internet weight management program. The IMI group recommendations included a 900-kcal liquid diet for 12 weeks or less, group behavioral counseling, structured diet, and choice of pharmacotherapy (sibutramine hydrochloride, orlistat, or diethylpropion hydrochloride) during months 3 to 7 and continued use of medications and maintenance strategies for months 8 to 24.

RESULTS

The mean age of participants was 47 years; 83% were women, and 75% were white. Retention rates were 51% for the IMI group and 46% for the UCC group (P = .30). After 2 years, the results were as follows: (1) among 390 randomized participants, 31% in the IMI group achieved a 5% or more weight loss and 7% achieved a 20% weight loss or more, compared with 9% and 1% of those in the UCC group. (2) The mean +/- SEM baseline observation carried forward analysis showed a weight loss of -4.9% +/- 0.8% in IMI and -0.2 +/- 0.3% in UCC. (3) Last observation carried forward analysis showed a weight loss of -8.3% +/- 0.79% for IMI, whereas UCC was -0.0% +/- 0.4%. (4) A total of 101 IMI completers lost -9.7% +/- 1.3% (-12.7 +/- 1.7 kg), whereas 89 UCC completers lost -0.4% +/- 0.7% (-0.5 +/- 0.9 kg); (P < .001 for all group differences). Many metabolic parameters improved.

CONCLUSION

Primary care practices can initiate effective medical management for extreme obesity; future efforts must target improving retention and weight loss maintenance.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00115063.

The multidimensional health locus of control scales: testing the factorial structure in sample of African American medical patients

OBJECTIVE

A fifth subscale was recently added to the widely used multidimensional health locus of control (MHLC) measure, and little is known about the factor structure of the MHLC with the new scale among African Americans from disadvantaged backgrounds. Also, few studies have examined differences in Health Locus of Control (HLOC) beliefs across medical patients from similar demographic backgrounds.

METHODS

We asked participants to complete a survey about HLOC beliefs and extracted biological markers from their medical charts. Participants were drawn from patients of internal medicine and infectious disease clinics at a charity hospital in Baton Rouge, Louisiana. In total, we surveyed 186 African American patients who were diagnosed with HIV/AIDS or type 2 diabetes.

RESULTS

Confirmatory factor analysis could not confirm a 5-factor structure; however, a new 3-factor structure was produced that includes 1) internal health beliefs, 2) external health beliefs, and 3) God health beliefs. Patients with HIV/AIDS reported more external and God HLOC beliefs than did patients with type 2 diabetes.

CONCLUSIONS

The factor structures that emerged from previous research may not be appropriate to use when conducting research with individuals from a low SES who are also from an ethnic/racial minority background. Our findings suggest a new 3-factor structure for the MHLC. Future research should examine whether patients with HIV/AIDS may benefit from interventions that target external beliefs to improve health behavior.

Weight loss maintenance following a primary care intervention for low-income minority women

Although the primary care setting offers an innovative option for weight loss interventions, there is minimal research examining this type of intervention with low-income minority women. Further, there is a lack of research on the long-term effects of these programs. The purpose of this investigation was to examine the weight loss maintenance of low-income African-American women participating in a primary care weight management intervention. A randomized controlled trial was conducted with overweight and obese women (N = 144) enrolled at two primary care clinics. Women received a 6-month tailored weight loss intervention delivered by their primary care physician and completed follow-up assessments 9, 12, and 18 months following randomization. The weight loss maintenance of the tailored intervention was compared to a standard care comparison group. The weight loss of intervention participants (-1.52 +/- 3.72 kg) was significantly greater than that of standard care participants (0.61 +/- 3.37 kg) at month 9 (P = 0.01). However, there was no difference between the groups at the 12-month or 18-month follow-ups. Participants receiving a tailored weight loss intervention from their physician were able to maintain their modest weight loss up to 3-6 months following treatment. Women demonstrated weight regain at the 18-month follow-up assessment, suggesting that more intensive follow-up in the primary care setting may be needed to obtain successful long-term weight loss maintenance.

Weight loss during the intensive intervention phase of the weight-loss maintenance trial

BACKGROUND

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).

METHODS

Eligible adults were aged > or =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.

RESULTS

Participants were 44% African American and 67% women; 79% were obese (BMI> or =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.

CONCLUSIONS

The WLM behavioral intervention successfully achieved clinically significant short-term weight loss in a diverse population of high-risk patients.

The psychosocial vulnerability model of hostility as a predictor of coronary heart disease in low-income African Americans

The current study examined social support and stress as mediators of the hostility-coronary heart disease (CHD) relationship as suggested by the psychosocial vulnerability model in a sample of low-income African Americans. Among 95 CHD patients and 30 healthy controls, hostility was negatively correlated with social support, but was not related to minor stress. CHD patients endorsed higher levels of hostility; however, the relationship between hostility and CHD status was diminished once stress and social support were included in the model. This study lends partial support for the psychosocial vulnerability model of hostility in African Americans, but suggests that the relationship between hostility and stress may be impacted by socioeconomic status.

Comparison of strategies for sustaining weight loss: the weight loss maintenance randomized controlled trial

CONTEXT

Behavioral weight loss interventions achieve short-term success, but re-gain is common.

OBJECTIVE

To compare 2 weight loss maintenance interventions with a self-directed control group.

DESIGN, SETTING, AND PARTICIPANTS

Two-phase trial in which 1032 overweight or obese adults (38% African American, 63% women) with hypertension, dyslipidemia, or both who had lost at least 4 kg during a 6-month weight loss program (phase 1) were randomized to a weight-loss maintenance intervention (phase 2). Enrollment at 4 academic centers occurred August 2003-July 2004 and randomization, February-December 2004. Data collection was completed in June 2007.

INTERVENTIONS

After the phase 1 weight-loss program, participants were randomized to one of the following groups for 30 months: monthly personal contact, unlimited access to an interactive technology-based intervention, or self-directed control. Main Outcome Changes in weight from randomization.

RESULTS

Mean entry weight was 96.7 kg. During the initial 6-month program, mean weight loss was 8.5 kg. After randomization, weight regain occurred. Participants in the personal-contact group regained less weight (4.0 kg) than those in the self-directed group (5.5 kg; mean difference at 30 months, -1.5 kg; 95% confidence interval [CI], -2.4 to -0.6 kg; P = .001). At 30 months, weight regain did not differ between the interactive technology-based (5.2 kg) and self-directed groups (5.5 kg; mean difference -0.3 kg; 95% CI, -1.2 to 0.6 kg; P = .51); however, weight regain was lower in the interactive technology-based than in the self-directed group at 18 months (mean difference, -1.1 kg; 95% CI, -1.9 to -0.4 kg; P = .003) and at 24 months (mean difference, -0.9 kg; 95% CI, -1.7 to -0.02 kg; P = .04). At 30 months, the difference between the personal-contact and interactive technology-based group was -1.2 kg (95% CI -2.1 to -0.3; P = .008). Effects did not differ significantly by sex, race, age, and body mass index subgroups. Overall, 71% of study participants remained below entry weight.

CONCLUSIONS

The majority of individuals who successfully completed an initial behavioral weight loss program maintained a weight below their initial level. Monthly brief personal contact provided modest benefit in sustaining weight loss, whereas an interactive technology-based intervention provided early but transient benefit.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00054925.

Promoting physical activity for low-income minority women in primary care

OBJECTIVE

To examine the effects of a primary-care weight management intervention on physical activity (PA) among overweight/obese women.

METHODS

This randomized controlled trial included 139 women (92% African American). The effects of a physician-delivered tailored intervention were compared with standard care. Repeated measures analyses of variance (ANOVA) were used to examine changes in PA (measured by a 7-day physical activity recall) and physical fitness (measured by heart rate recovery following exercise).

RESULTS

Although the intervention group demonstrated an increase in PA, this did not differ significantly from standard care. A significantly greater proportion of intervention participants (90%) achieved current PA recommendations compared with standard care (77%), P<.03.

CONCLUSION

These results provide novel information suggesting that a physician-delivered intervention may have limited effectiveness for increasing PA among this at-risk population.

Botanicals and the metabolic syndrome

Metabolic syndrome describes the human condition characterized by the presence of coexisting traditional risk factors for cardiovascular disease, such as hypertension, dyslipidemia, glucose intolerance, and obesity, in addition to nontraditional cardiovascular disease risk factors, such as inflammatory processes and abnormalities of the blood coagulation system. Although the specific etiology for metabolic syndrome is not known, insulin resistance--a clinical state in which a normal or elevated insulin concentration reflects an impaired biological response--is present and is considered a key pathophysiologic abnormality. As such, metabolic syndrome can be considered to be a prediabetic state and contributes greatly to increased morbidity and mortality in humans. Given the public health significance of metabolic syndrome, successful strategies are direly needed to intervene in its development. As such, nutritional supplementation with botanicals that effectively address pathogenic mechanisms, combined with the acceptance and widespread use of botanical supplements by the general public, represents an attractive, novel, and potentially effective approach to the problem. Thus, the overall goal of our botanical research center is to comprehensively evaluate botanicals in addressing the pathophysiologic mechanisms that lead to the development of insulin resistance and metabolic syndrome. Currently, each of the 3 research projects evaluates a specific botanical [Russian tarragon (Artemisia dracunculus L), shilianhua (Sinocrassula indica), and grape (Vitus vinifera) anthocyanins] and assesses the effect on pathogenic mechanisms leading to the development of insulin resistance. With the completion of our research, we anticipate a better understanding of the cellular mechanisms by which insulin resistance develops and the role of botanicals in modulating the progression to metabolic syndrome.

Effect of group racial composition on weight loss in African Americans

OBJECTIVE

We do not know how racial composition of a group influences behavior change for African Americans (AAs) in group-based weight loss programs. We tested the hypothesis that AA who participate in all AA weight loss intervention groups will lose more weight than AA who participate in mixed race groups.

METHODS AND PROCEDURES

This observational study was ancillary to Phase 1 of the Weight Loss Maintenance Study, a multi-center trial of strategies to maintain weight loss after a 20-week behavior modification program. Three of four centers recruited several all-AA intervention groups. Remaining groups were combinations of AA and non-AA participants. All participants received the same weight loss intervention. Change in weight was the primary outcome, comparing participants of all-AA groups with AA participants of mixed race groups conducted by the same AA interventionists. Secondary outcomes included measures of intervention adherence and behavior change.

RESULTS

Participants of all-AA groups (n = 271) were comparable to other AA participants (n = 106). The mean proportion of AA in mixed race groups was 56%. All-AA group participants had similar weight loss as those in mixed groups (-4.2 vs. -4.2 kg, P = 0.97). There were no differences between the groups in mean number of sessions attended or changes in dietary intake.

DISCUSSION

Significant weight loss was observed in both groups, with no effect of group composition on adherence or weight loss outcomes. Special logistics to accommodate all-AA groups may not be necessary. Despite varying instructional environments, AA appeared to respond positively to intervention messages with significant changes in dietary intake, physical activity (PA), and weight.

Design and implementation of an interactive website to support long-term maintenance of weight loss

Background

For most individuals, long-term maintenance of weight loss requires long-term, supportive intervention. Internet-based weight loss maintenance programs offer considerable potential for meeting this need. Careful design processes are required to maximize adherence and minimize attrition.

Objective

This paper describes the development, implementation and use of a Web-based intervention program designed to help those who have recently lost weight sustain their weight loss over 1 year.

Methods

The weight loss maintenance website was developed over a 1-year period by an interdisciplinary team of public health researchers, behavior change intervention experts, applications developers, and interface designers. Key interactive features of the final site include social support, self-monitoring, written guidelines for diet and physical activity, links to appropriate websites, supportive tools for behavior change, check-in accountability, tailored reinforcement messages, and problem solving and relapse prevention training. The weight loss maintenance program included a reminder system (automated email and telephone messages) that prompted participants to return to the website if they missed their check-in date. If there was no log-in response to the email and telephone automated prompts, a staff member called the participant. We tracked the proportion of participants with at least one log-in per month, and analyzed log-ins as a result of automated prompts.

Results

The mean age of the 348 participants enrolled in an ongoing randomized trial and assigned to use the website was 56 years; 63% were female, and 38% were African American. While weight loss data will not be available until mid-2008, website use remained high during the first year with over 80% of the participants still using the website during month 12. During the first 52 weeks, participants averaged 35 weeks with at least one log-in. Email and telephone prompts appear to be very effective at helping participants sustain ongoing website use.

Conclusions

Developing interactive websites is expensive, complex, and time consuming. We found that extensive paper prototyping well in advance of programming and a versatile product manager who could work with project staff at all levels of detail were essential to keeping the development process efficient.

Trial Registration

clinicaltrials.gov NCT00054925

Effects of PREMIER Lifestyle Modifications on Participants With and Without the Metabolic Syndrome

Lifestyle modification can reduce blood pressure and lower cardiovascular risk. Established recommendations include weight loss, sodium reduction, and increased physical activity. PREMIER studied the effects of lifestyle interventions based on established recommendations alone and with the addition of the Dietary Approaches to Stop Hypertension (DASH) dietary pattern. This analysis aimed to assess the interventions’ impact on cardiometabolic variables in participants with, compared with those without, metabolic syndrome. The primary outcome was 6-month change in systolic blood pressure. Participants with prehypertension or stage-1 hypertension were randomly assigned to an advice only control group, a 6-month intensive behavioral intervention group of established recommendations (EST), or an established recommendations plus DASH group (EST+DASH). Metabolic syndrome was defined per National Cholesterol and Education Program Adult Treatment Panel III. We used general linear models to test intervention effects on change in blood pressure, lipids, and insulin resistance (homeostasis model assessment), in subgroups defined by the presence or absence of metabolic syndrome. Of 796 participants, 399 had metabolic syndrome. Both EST and EST+DASH reduced the primary outcome variable, systolic blood pressure. Within the EST+DASH group, those with and without metabolic syndrome responded similarly ( P =0.231). However, within EST, those with metabolic syndrome had a poorer response, with a decrease in systolic blood pressure of 8.4 mm Hg versus 12.0 mm Hg in those without metabolic syndrome ( P =0.002). Thus, metabolic syndrome attenuated the systolic blood pressure reduction of EST, but this attenuation was overcome in EST+DASH. Finally, diastolic blood pressure, lipids, and homeostasis model assessment responded similarly to both interventions regardless of metabolic syndrome status. Our data suggest that strategies for lowering BP in individuals with metabolic syndrome may be enhanced by recommendations to adopt the DASH dietary pattern.

Attitudes Toward Health Care Providers and Appointment Attendance in HIV/AIDS Patients

Patients with HIV/AIDS are likely to have numerous interactions with health care providers (HCPs) during the course of their disease. Research has shown that satisfaction with one's HCP is related to better medication adherence in patients with HIV/AIDS. Although a patient's attitude toward his or her HCP is important, little has been done to assess how it relates to appointment attendance. The current study assessed how attitudes toward HCPs as well as social support and depression relate to outpatient appointment attendance. Further, this study used a newly developed, psychometrically valid scale to assess specific patient attitudes toward HCPs including those related to disease stigma. Participants were predominantly low-income African American men (N = 109) recruited from a public southern HIV clinic. Analyses indicated that attitudes toward HIV HCPs, social support, and medication status but not depression or satisfaction with social support were associated with appointment attendance.

A stage-targeted physical activity intervention among a predominantly African-American low-income primary care population

PURPOSE

To examine the efficacy of a stage-targeted physical activity intervention among low-income African-Americans.

METHODS

207 participants were randomly assigned to groups and administered baseline measures. Intervention participants were mailed stage-targeted physical activity information, whereas control participants received low-sodium diet brochures. Measures were readministered by phone 1 and 6 months later, with response rates of 69% and 46%, respectively.

RESULTS

69% of participants were African-American and 64% had a monthly household income of < $1000. A doubly-multivariate analysis of variance indicated that intervention participants reported more physical activity than control participants at 1 month (F(1, 204) = 4.03, p < .05). Unlike control participants, intervention participants reported significant stage progression at 1 month, according to a McNemar chi2 test. Gains attenuated by 6 months.

CONCLUSIONS

The current study supports the use of this intervention among low-income African-Americans. Limitations include use of self-report measures and small sample size.

Cultural characteristics of African Americans: implications for the design of trials that target behavior and health promotion programs

OBJECTIVE

To identify African American cultural characteristics that may be used to modify clinical trial designs and behavioral programs aimed at losing weight and maintaining weight loss.

DESIGN

Focus group discussions.

SETTING

University-affiliated biomedical research center.

PARTICIPANTS

Thirty-one African American men and women who completed the screening process, but were ineligible for the Weight Loss Maintenance (WLM) trial, participated in one of five focus group sessions. WLM is a randomized controlled trial that compares two lifestyle interventions for preventing weight regain in individuals who have successfully lost weight in a group-based behavioral weight loss program.

RESULTS

Nine themes emerged as cultural characteristics specific to African Americans seeking participation in a lifestyle change program: (1) religion is a powerful force; (2) family structure; (3) integration dismantled the African American family; (4) general mistrust of Caucasians; (5) African Americans are undervalued and not respected as a people; (6) limited resources equal limited ability to make lifestyle changes; (7) preservation of an explicit ethnic identity; (8) education is the key to success as an African American; and (9) communication skills are vital.

CONCLUSIONS

Identifying cultural characteristics specific to African Americans may help investigators design clinical trials that will enhance outcomes and improve the generalizability of results in ethnic minority populations.

A primary care weight management intervention for low-income African-American women

OBJECTIVE

To determine whether a tailored weight management program, addressing the needs of obese, low-income African-American women, would produce greater weight loss than standard medical care.

RESEARCH METHODS AND PROCEDURES

A randomized, controlled trial was conducted between 1999 and 2003 with 144 overweight or obese women (predominantly African-American) enrolled at two primary care clinics. Four physicians at each clinic were randomly assigned to provide either tailored weight management interventions or standard care. The tailored condition consisted of six monthly outpatient visits lasting approximately 15 minutes each, which included personalized materials and messages. The main outcome was body weight change.

RESULTS

The intervention group lost more weight than the standard care group (p = 0.03). The tailored group lost a mean (standard deviation) of 2.0 (3.2) kg by Month 6. The standard care group gained 0.2 (2.9) kg. More participants in the tailored group lost weight (79% vs. 47%; p = 0.04).

DISCUSSION

Obese, low-income, African-American women provided with 90 minutes of physician-delivered, tailored weight management instruction over 6 months achieved greater weight loss than those receiving standard medical care. The primary care physician can be effective in delivering weight loss interventions, and the primary care clinic may be a useful setting to implement weight management interventions.