Walker S. Carlos Poston

Pharmacotherapy for obesity: a quantitative analysis of four decades of published randomized clinical trials

AIM: This article provides the first comprehensive meta-analysis of randomized clinical trials of medications for obesity.METHOD: Based on stringent inclusionary criteria, a total of 108 studies were included in the final database. Outcomes are presented for comparisons of single and combination drugs to placebo and for comparisons of medications to one another.RESULT: Overall, the medications studied produced medium effect sizes. Four drugs produced large effect sizes (ie d>0.80; amphetamine, benzphetamine, fenfluramine and sibutramine). The placebo-subtracted weight losses for single drugs vs placebo included in the meta-analysis never exceeded 4.0 kg. No drug, or class of drugs, demonstrated clear superiority as an obesity medication. Effects of methodological factors are also presented along with suggestions for future research.

Nondieting Versus Dieting Treatment for Overweight Binge-Eating Women

This study evaluated the effectiveness of nondieting versus dieting treatments for overweight, binge-eating women. Participants (N = 219) were randomly assigned to 1 of 3 groups: diet treatment (DT), nondiet treatment (NDT), or wait-list control (WLC). DT received a balanced-deficit diet reinforced with behavioral strategies. NDT received therapy designed to help participants break out of their dieting cycles. Treatment in both conditions was administered in weekly groups for 6 months, followed by 26 biweekly maintenance meetings, for a total of 18 months of contact. At 6 months posttreatment, DT lost 0.6 kg while NDT gained 1.3 kg. Both treatment groups reduced their Binge Eating Scale scores significantly more than WLC. At 18-month follow-up, both treatment groups experienced weight gain but maintained similar reductions in binge eating. Results indicate that neither intervention was successful in producing short- or long-term weight loss. Therapist biases, which may have affected treatment integrity, and other methodological issues are discussed in relation to the small weight losses achieved.

Weight Management Using the Internet: A Randomized Controlled Trial

BACKGROUND Most weight-loss research targets obese individuals who desire large weight reductions. However, evaluation of weight-gain prevention in overweight individuals is also critical as most Americans become obese as a result of a gradual gain of 1-2 pounds per year over many years. METHOD This study evaluated the efficacy of an Internet-based program for weight-loss and weight-gain prevention with a two-group, prospective, randomized controlled trial. A military medical research center with a population of 17,000 active-duty military personnel supplied 446 overweight individuals (222 men; 224 women) with a mean age of 34 years and a mean BMI of 29. Recruitment and study participation occurred 2003-2005 and data were analyzed in 2006. Participants were randomly assigned to receive the 6-month behavioral Internet treatment (BIT, n=227) or usual care (n=224). Change in body weight, BMI, percent body fat, and waist circumference; presented as group by time interactions, were measured. RESULTS After 6 months, completers who received BIT lost 1.3 kg while those assigned to usual care gained 0.6 kg (F((df=366))=24.17; I<0.001). Results were similar for the intention-to-treat model. BIT participants also had significant changes in BMI (-0.5 vs +0.2 kg/m(2); F((df=366))=24.58); percent body fat (-0.4 vs +0.6%; F((df=366))=10.45); and waist circumference (-2.1 vs -0.4 cm; F((df=366))=17.09); p<0.001 for all. CONCLUSIONS Internet-based weight-management interventions result in small amounts of weight loss, prevent weight gain, and have potential for widespread dissemination as a population health approach. TRIAL REGISTRATION NCT00417599.

Depression predicts disability in long-term chronic pain patients.

Purpose : Investigators have examined factors that predict treatment outcome and disability status in chronic pain patients, including psychopathology and personality characteristics with equivocal results. The purpose of this study was to evaluate the usefulness of personality characteristics, depression, and personality disorders in predicting disability status in pain patients with long-term follow-up. The setting was a rehabilitation hospital in Southern Sweden. Method : Subjects were 184 pain patients (mean age=43.4 (10.8) years; 72.8% female) who had no more than 365 sick leave days (Mean sick leave days=132.7 (128.2)) prior to the baseline personality and psychiatric evaluation. The baseline evaluation consisted of a psychiatric interview that included the administration of the Structured Clinical Interview for DSM-IV Screen Questionnaire (SCID-II), the Montgomery-Åsberg Depression Rating Scale (MADRS), and the Karolinska Scales of Personality (KSP). Disability status was assessed by insurance record review a minimum of two-and-a-half years after baseline evaluation. Results : Multivariate logistic regression suggests that age (OR=1.09, 95% CI=1.02-1.18; p =0.013), number of sick leave days prior to evaluation (OR=1.01, 95% CI=1.01-1.02; p =0.018), and baseline diagnosis of depression significantly predicted subsequent disability status (OR=7.04, 95% CI=1.15-42.93; p =0.034). Baseline personality traits and the diagnosis of a personality disorder were not useful predictors of disability status in our sample. Conclusions : These data suggest that depression, but not personality disorders characteristics, was an important disability predictor in chronic pain patients with extended follow-up.

The prevalence of overweight, obesity, and substandard fitness in a population-based firefighter cohort.

Objective: To examine the prevalence of overweight and obesity in firefighters. Methods: Body mass index (BMI), waist circumference, and body fat percentage (BF%) were assessed in 478 career and 199 volunteer male firefighters from randomly selected departments. Results: High prevalence rates of overweight + obesity (BMI ≥ 25 kg/m2) and obesity (BMI ≥ 30 kg/m2) were found in career (79.5%; 33.5%) and volunteer firefighters (78.4%; 43.2%). False-positive obesity misclassification based on BMI, compared to waist circumference and BF%, was low (9.8% and 2.9%, respectively). False negatives were much higher: 32.9% and 13.0%. Obese firefighters demonstrated unfavorable cardiovascular disease (CVD) profiles. Conclusions: The prevalence of overweight and obesity exceeded that of the US general population. Contrary to common wisdom, obesity was even more prevalent when assessed by BF% than by BMI, and misclassifying muscular firefighters as obese by using BMI occurred infrequently.

Blood pressure and symptoms of depression and anxiety: a prospective study

This study investigated whether symptoms of depression and anxiety were related to the development of elevated blood pressure in initially normotensive adults. The studys hypothesis was addressed with an existing set of prospective data gathered from an age-, sex-, and weight-stratified sample of 508 adults. Four years of follow-up data were analyzed both with logistic analysis, which used hypertension (blood pressure > or =140 mm Hg systolic or 90 mm Hg diastolic) as the dependent variable, and with multiple regression analysis, which used change in blood pressure as the dependent variable. Five physical risk factors for hypertension (age, sex, baseline body mass index, family history of hypertension, and baseline blood pressure levels) were controlled for in the regression analyses. Use of antidepressant/antianxiety and antihypertensive medications were controlled for in the study. Of the 433 normotensive participants who were eligible for our study, 15% had missing data in the logistic regression analysis focusing on depression (n = 371); similarly, 15% of the eligible sample had missing data in the logistic regression using anxiety as the psychological variable of interest (n = 370). Both logistic regression analyses showed no significant relationship for either depression or anxiety in the development of hypertension. The multiple regression analyses (n = 369 for the depression analysis; n = 361 for the anxiety analysis) similarly showed no relationship between either depression or anxiety in changes in blood pressure during the 4-year follow-up. Thus, our results do not support the role of depressive or anxiety symptoms in the development of hypertension in our sample of initially normotensive adults.

Weight loss in overweight Mexican American children: a randomized, controlled trial.

OBJECTIVES. Childhood overweight has increased significantly in the past 20 years, with the highest rates noted among Mexican Americans. Although this minority group is in significant need of intervention, few programs have demonstrated actual decreases in weight. In this study we evaluated an intensive healthy lifestyle program designed to result in weight reduction for overweight Mexican American children. We hypothesized that children randomly assigned to an intensive intervention would significantly reduce their standardized BMI when compared with children randomly assigned to a self-help condition. PATIENTS AND METHODS. A total of 60 children (33 boys; 55%) between the ages of 10 and 14 years at or above the 85th percentile for BMI were randomly assigned to a 6-month intensive-intervention or self-help condition. RESULTS. Children in the intensive-intervention condition significantly reduced their standardized BMI when compared with the children in the self-help condition. The change in standardized BMI was significantly different at both 3 and 6 months, with intensive-intervention participants showing greater decreases in weight. CONCLUSIONS. Overall, the results were promising, suggesting that an intensive, individualized intervention may be an effective means for promoting weight loss in overweight Mexican American children.

How Does the Built Environment Relate to Body Mass Index and Obesity Prevalence Among Public Housing Residents

Purpose. This study examined associations of environmental variables with obesity prevalence and individual body mass index (BMI) among impoverished residents of public housing developments. Design. Cross-sectional data were drawn from two studies in the same Midwestern metropolitan area of participants within neighborhoods. Setting. Pathways to Health interviewed housing development residents and Understanding Neighborhood Determinants of Obesity assessed built environment factors in the surrounding neighborhoods (i.e., 800–m radius from center of housing development). Subjects. Four hundred twenty-one residents participated (mean age = 43.8 years; 72.0% women, 59.6% high school degree, 79.6% African-American). Fifty-five physical activity resources were identified and assessed. Measures. Demographics and measured weights and heights were obtained for participants. The Physical Activity Resource Assessment measured the type, accessibility, features, amenities, qualities, and incivilities of neighborhood physical activity resources. Neighborhood street connectivity was also measured. Results. Average age-adjusted BMI was 31.4 (SD = 1.3), with 45% of residents obese. High negative correlations were found between BMI and street connectivity (p = .05) and between obesity prevalence and resource accessibility (p = .09), number of amenities (p = .04), and amenity quality (p = .04). Higher resource accessibility, feature quality, number of amenities, and fewer incivilities per resource accounted for 71% of obesity variance (p < .05). Male gender and higher feature quality, F(11, 407)37.19 and 12.66, p < .001, predicted lower BMI among residents. Conclusion. Supportive neighborhood environments were related to lower obesity prevalence and lower BMI among residents.

Associations between the built environment and physical activity in public housing residents

BackgroundEnvironmental factors may influence the particularly low rates of physical activity in African American and low-income adults. This cross-sectional study investigated how measured environmental factors were related to self-reported walking and vigorous physical activity for residents of low-income public housing developments.MethodsPhysical activity data from 452 adult residents residing in 12 low-income housing developments were combined with measured environmental data that examined the neighborhood (800 m radius buffer) around each housing development. Aggregated ecological and multilevel regression models were used for analysis.ResultsParticipants were predominately female (72.8%), African American (79.6%) and had a high school education or more (59.0%). Overall, physical activity rates were low, with only 21% of participants meeting moderate physical activity guidelines. Ecological models showed that fewer incivilities and greater street connectivity predicted 83% of the variance in days walked per week, p < 0.001, with both gender and connectivity predicting days walked per week in the multi-level analysis, p < 0.05. Greater connectivity and fewer physical activity resources predicted 90% of the variance in meeting moderate physical activity guidelines, p < 0.001, and gender and connectivity were the multi-level predictors, p < 0.05 and 0.01, respectively. Greater resource accessibility predicted 34% of the variance in days per week of vigorous physical activity in the ecological model, p < 0.05, but the multi-level analysis found no significant predictors.ConclusionThese results indicate that the physical activity of low-income residents of public housing is related to modifiable aspects of the built environment. Individuals with greater access to more physical activity resources with fewincivilities, as well as, greater street connectivity, are more likely to be physically active.

Evaluation of a culturally appropriate intervention to increase physical activity.

OBJECTIVE To evaluate a culturally appropriate intervention to increase activity in overweight Mexican American women. METHODS Participants were randomly assigned to a physical activity program or wait-list control. RESULTS Treated participants were not more active than controls at 6 or 12 months. In addition, we found no significant differences in the proportion of individuals who met an objective criterion for physical activity from baseline to 6 months in the treatment or control groups. CONCLUSION The intervention did not increase physical activity in this population. Differences in baseline activity and contamination of the control group may partially account for the outcome.