G. Ken Goodrick

Comparison of 2-Year Weight Loss Trends in Behavioral Treatments of Obesity: Diet, Exercise, and Combination Interventions

OBJECTIVE The effects of three cognitive-behavioral weight control interventions for adults were compared: diet only, exercise only, and a combination of diet and exercise. This article reports 2-year follow-up data. DESIGN The three interventions were compared in a randomized, experimental design. SUBJECTS A total of 127 men and women who were at least 14 kg overweight (according to height-weight tables) were recruited from an urban community and assigned randomly to the experimental conditions. INTERVENTION The dietary intervention was a low-energy eating plan adjusted to produce a 1 kg/week loss of weight. The exercise component involved training in walking and a home-based program of up to five exercise periods per week. There were 12 weekly instructional sessions, followed by 3 biweekly and 8 monthly meetings. All sessions were led by registered dietitians. OUTCOME MEASURES Changes in body weight. STATISTICAL ANALYSES Analysis of variance for weight changes and repeated measures analysis of variance for weight change trends. RESULTS At 1 year, no significant differences were noted among the three groups. The diet-only group lost 6.8 kg, the exercise-only group lost 2.9 kg, and the combination group lost 8.9 kg (P=.09). During the second year, the diet-only group regained weight--reaching 0.9 kg above baseline; the combination group regained to 2.2 kg below baseline; and the exercise-only group regained slightly to 2.7 kg below baseline (P=.36). Repeated measures analysis of variance showed a group-by-time interaction (P=.001); data for the dieting groups best fit a U-shaped regain curve (P=.001). APPLICATIONS The results suggest that dieting is associated with weight loss followed by regain after treatment ends, whereas exercise alone produced smaller weight losses but better maintenance. The large outcome variability and unequal difficulty of the regimens across groups limit the generalizability of the findings.

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.

Limitations of behavioral treatment of obesity: Review and analysis

Over 200 articles have been published describing behavior modification programs for weight reduction. We reviewed the group studies that reported weight data at least 1 year posttreatment. Evaluating these studies, we concluded that although changes in weight do occur, these changes are almost always clinically small, variability among patients is large, and further weight losses do not occur following the end of formal treatment. The weight lost during treatment may be explained by changes in specific eating behaviors caused by therapist contact rather than the effect of self-applied behavioral techniques on eating. Support for the effectiveness of each of the specific techniques to produce lasting weight loss or behavioral change was also lacking. Suggestions for future research in this area are given.

Psychological correlates of weight fluctuation

This investigation attempted to determine psychological correlates of weight fluctuation in a sample of 497 normal weight and obese adults who were enrolled in a prospective, natural history study. Subjects were stratified by gender, obesity, and age and classified as weight maintainers, gainers, or losers based on their changes in weight over a 1-year period. Subjects were further classified as either weight fluctuators or nonfluctuators based on historical self-report. Nonfluctuators reported significantly higher general well-being, greater eating self-efficacy, and lower stress than weight fluctuators, regardless of body weight. Weight maintainers had more favorable eating self-efficacy related to negative affect than weight gainers. Results suggest that weight fluctuation is strongly associated with negative psychological attributes in both normal weight and obese individuals. Future research should focus on the assessment and treatment of weight fluctuation and on weight maintenance, irrespective of weight status.

Factors common to successful therapy for the obese patient

The majority of patients treated for obesity regain lost weight after treatment. We speculate on what might be done to improve long-term success rates by examining the factors associated with success or relapse. An emphasis on exercise and prescribing more gradual changes in diet and exercise appears to be associated with better outcomes. There may be a need to conceptualize obesity as a food dependency disorder not amenable to self-control strategies. External social control through peer support groups may be indicated to help patients through temptations.

Attributes of successful approaches to weight loss and control

Abstract Most weight loss treatments result in only temporary losses, followed by slow regain. This paper examines those factors that are correlated with the most favorable results in terms of loss and maintenance of loss. Weight loss is positively related to self-monitoring, goal setting, social support, and length of treatment. Maintenance of weight loss is correlated with regular physical activity, self-monitoring, and continued contact with therapists. Regain is associated with inconsistent and restrictive dieting, life stress, negative coping style, and emotional or binge eating patterns. The implications drawn from these findings are (a) normalize eating patterns, (b) emphasize exercise, (c) ensure social support, (d) set realistic goal weights, (e) focus on health rather than appearance, (f) focus on self-esteem, and (g) target binge eating.

A Functional Food Product for the Management of Weight

Referee: Dr. Harold S. Solomon, Associate Clinical Professor of Medicine, Beth Israel-Deaconesss, 25 Boylston Street, #311, Chestnut Hill, MA 02467 More than half of Americans have a body mass index of 25 kg/m2 or more, which classifies them as overweight or obese. Overweight or obesity is strongly associated with comorbidities such as type 2 diabetes mellitus, hypertension, heart disease, gall bladder disease, and sleep apnea. Clearly, this is a national health concern, and although about 30 to 40% of the obese claim that they are trying to lose weight or maintain weight after weight loss, current therapies appear to have little effect. None of the current popular diets are working, and there is room for innovation. With the advancing science of nutrition, several nutrients—low-glycemic-index carbohydrates, 5-hydroxytryptophan, green tea extract, and chromium—have been identified that may promote weight loss. The first two nutrients decrease appetite, green tea increases the 24-h energy expenditure, and chromium promotes the composition of the weight lost to be fat rather than lean tissue. These have been assembled in efficacious doses into a new functional food product and described in this review. The product is undergoing clinical testing; each component has already been shown to promote weight loss in clinical trials.

Personality and the prediction of weight loss and relapse in the treatment of obesity

OBJECTIVE This prospective study examined whether stable personality traits, as measured by the Karolinska Scales of Personality (KSP), predicted initial weight loss or long-term maintenance in obesity patients. METHOD The KSP was administered to 102 obese patients prior to entering an 8-week weight loss program. Patients were weighed again at the end of treatment and at 3- and 12-month follow-up. RESULTS The KSP did not predict initial weight loss after the 8-week program. Several of the KSP scales (Muscle Tension, Monotony Avoidance, Suspicion, and Guilt) had weak associations with 12-month relapse status. Weight gain at the 3-month follow-up was the strongest predictor of 12-month relapse status (O.R. = 0.46; 95% C.I. = 0.32, 0.66). DISCUSSION Personality traits, as measured by the KSP, do not appear to be important predictors of initial weight loss or 12-month relapse status. Personality assessment may not substantially contribute to predicting treatment outcome in obesity research.

Effect of financial incentives on improvement in medical quality indicators for primary care

Purpose:The efficacy of rewarding physicians financially for preventive services is unproven. The objective of this study was to evaluate the effect of a physician pay-for-performance program similar to the Medicare Physician Quality Reporting Initiative program on quality of preventive care in a network of community health centers. Methods:A retrospective review of administrative data was done to evaluate a natural quasi-experiment in a network of publicly funded primary care clinics. Physicians in 6 of 11 clinics were given a financial incentive twice the size of the current Centers for Medicare and Medicaid Services’ incentive for achieving group targets in preventive care that included cervical cancer screening, mammography, and pediatric immunization. They also received productivity incentives. Six years of performance indicators were compared between incentivized and nonincentivized clinics. We also surveyed the incentivized clinicians about their perception of the incentive program. Results:Although some performance indicators improved for all measures and all clinics, there were no clinically significant differences between clinics that had incentives and those that did not. A linear trend test approached conventional significance levels for Papanicolaou smears (P = .08) but was of very modest magnitude compared with observed nonlinear variations; there was no suggestion of a linear trend for mammography or pediatric immunizations. The survey revealed that most physicians felt the incentives were not very effective in improving quality of care. Conclusion:We found no evidence for a clinically significant effect of financial incentives on performance of preventive care in these community health centers. Based on our findings and others, we believe there is great need for more research with strong research designs to determine the effects, both positive and negative, of financial incentives on clinical quality indicators in primary care.

Response of free-living adults to behavioral treatment of obesity: Attrition and compliance to exercise

The effects of a behavior modification program were studied in a free-living population of mildly obese adults over a one-year period. A total of 165 subjects were randomly assigned to control or to exercise-only, diet-only, or exercise-plus-diet behavior modification groups. The diet plan consisted of a prudent, reduced-fat regimen. Most subjects chose brisk walking for exercise. After the first 3 months, diet intervention was associated with a significant reduction in weight, percent body fat, and waist circumference. After 12 months, mean weight of the exercise-plus-diet group was lower than that of the exercise-only group. Interpretation of these results is difficult, because many of the subjects failed to adhere to the behavioral recommendations. Problems in treating obese adults without close therapist scrutiny are discussed.