Nonpurging binge eaters versus nonbinge eaters and treatment retention for adult obesity

Dropout from obesity treatment has been a major factor associated with weight control failure, with few reliable predictors of dropouts or completers. Previous studies have tended to treat obese people as a homogeneous group with standard behavior modification-based interventions. Current research indicates there may be subgroups within the obese population, binge eaters and nonbinge eaters, who have different dropout rates. Current studies also recommend focusing on the subset of this subgroup that does not engage in purging (vomiting, laxative abuse, or excessive exercise) to compensate for binge eating. This research uses a secondary dataset (N = 156) from a prospective study in which participants were randomized to a Food Dependency (FD) and a Behavioral Self-Management (BSM) group for weight reduction. Criteria for subjects in the original study included (1) scoring higher on the existing Binge Eating Scale (BES) in order to ensure enrollment of more binge eaters and (2) no compensatory purging behavior for binge eating. Subjects were then reclassified in this study as binge eaters or nonbinge eaters using the more stringent proposed 1994 DSM-IV criteria for Binge Eating Disorder (BED). Subjects were followed for dropout. Variables studied were binge status, age at obesity onset, age at study baseline, class instructor, number of previous weight loss attempts, race, marital status, body mass index (BMI kg/m$\sp2$), type of intervention, work status, educational level, and social support. Stepwise backward regression Cox survival analysis indicated binge status had a consistent, statistically significant protective effect on dropout in which binge eaters were half as likely to dropout versus nonbinge eaters (p = 0.04). Cox proportional hazards analysis indicated no statistical difference in dropout by type of intervention (FD, p = 0.13; BSM, p = 0.80) when controlling for binge status. All other variables did not reach significance, which is consistent with the literature. Implications of these findings suggest that (1) the proposed 1994 DSM-IV criteria for BED is a more useful classification that the existing DSM-III-R criteria, and (2) the identification of subgroups among obese subjects is an important step in dropout and weight loss intervention research. Future research can confirm this finding. ^

Food intake in nonpurging obese women who binge eat before and after a behavioral weight loss program

Little is known about the impact of behavioral programs to decrease binge eating in obese persons who do not purge. This study was conducted to compare the amount of change in the reduction of binge days and selected nutrients in women who had joined a behavioral weight loss program. Forty-six women in the behavioral self management (BSM) group and thirty-six women in the Wait List Control (WLC) groups completed seven day food records at baseline and six months. These records were analyzed for calories, percentage of calories from protein, carbohydrate, fat and dietary fiber/ 1000 calories and were marked as "binge" or "nonbinge" days. Foods were also divided into 12 food groups but only six contributing to fat intake were chosen for analysis: dairy; fat; grains and starchy vegetables; meat, fish, and poultry; meat, fish, and poultry combinations; snacks and desserts. At six months, there was no difference in the amount of change in any of the selected nutrients between the BSM and WLC groups or in the amount of change within each food group except in the meat, fish, and poultry combination and in the snacks and desserts groups because both groups experienced similar changes at six months. Binge and nonbinge day nutrient analysis by BSM and WLC showed that at baseline and six months within the BSM group, calories increased significantly on binge days. Within the WLC group at six months, percentage of calories from protein was significantly decreased on binge days.^ The significant finding of this study was the reduction in the amount of change in the number of binge days at six months between the BSM and WLC groups ($-$2.2 versus $-$1.1 respectively). These data suggest that behavioral programs can successful reduce binge days, but that significant change in food intake may require more intensive treatment. ^