Randomized Controlled Trial of Behavioral Weight Loss and Stepped Care for Binge-Eating Disorder: 12-Month Follow-up

Abstract

Objective: This study aimed to examine longer-term effects of behavioral weight loss (BWL) and Stepped Care for binge-eating disorder and obesity through 12-month follow-up after completing treatments.

Methods: A total of 191 patients with binge-eating disorder/obesity were randomized to 6 months of BWL (n = 39) or Stepped Care (n = 152). Within Stepped Care, patients began BWL (1 month), treatment responders continued BWL, nonresponders switched to cognitive behavioral therapy, and all were randomized (double-blind) to weight-loss medication or placebo (5 months). Patients were independently assessed throughout/after treatment and at 6- and 12-month follow-ups.

Results: Intent-to-treat analyses of remission rates revealed that BWL and Stepped Care did not differ significantly at posttreatment (74.4% vs. 66.5%), 6-month follow-up (38.2% vs. 33.3%), or 12-month follow-up (44.7% vs. 41.0%). Mixed models of binge-eating frequency indicated significant reductions through posttreatment but no significant changes or differences between BWL and Stepped Care during follow-up. Mixed models revealed significant weight loss with no differences between BWL and Stepped Care (5.1% vs. 5.8%) at posttreatment and significant time effects (larger percent weight loss at 6-month than at 12-month follow-up) with no differences between BWL and Stepped Care (-5.1% vs. -5.2% and -3.4% vs. -5.0%, respectively).

Conclusions: Binge-eating improvements and weight loss produced by BWL and adaptive Stepped Care did not differ significantly 12 months after completing treatments.

Trial registration: ClinicalTrials.gov NCT00829283.

Conflict of interest statement

Potential Conflicts of interest: The authors declare no conflicts of interest. Dr. Grilo reports broader interests, which did not influence this research, including: Consultant to Sunovion and Weight Watchers; Honoraria for lectures, CME activities, and lectures at scientific conferences, and Royalties from Guilford Press and Taylor & Francis Publishers for academic books.

© 2020 The Obesity Society.

Figures

Figure 1.. Flow of participants throughout study.

Note. *In Stepped Care, N=10 were not stratified (thus yielding N=142) because they were either withdrawn (n=1 due to pregnancy) or dropped out (n=4 due to time commitment, n=1 due to relocating out of state, n=1 due to dissatisfaction with weight loss, and n=3 for unknown reasons).

Figure 2.. Binge-eating remission rates for BWL (Standard) and Stepped Care across follow-up assessments.

Percentage of participants in the two overall acute treatment conditions (BWL (Standard) and Stepped Care)) who achieved remission from binge eating at post-treatment, 6-month follow-up, and 12-month follow-up assessments. Remission is defined as zero binge-eating episodes for the previous month based on the Eating Disorder Examination Interview. Intent-to-treat analysis for all randomized participants (n=191) with instances of missing data coded as non-remission. Note: BWL = behavioral weight loss.

Figure 3.. Binge-eating remission rates for BWL (Standard) and for the four arms within Stepped Care across follow-up assessments.

Percentage of participants in BWL (Standard) and in the four arms within Stepped Care who achieved remission from binge eating at post-treatment, 6-month follow-up, and 12-month follow-up assessments. Remission is defined as zero binge-eating episodes for the previous month based on the Eating Disorder Examination – Interview. Intent-to-treat analysis for all randomized participants with baseline carried forward method for instances of missing data (i.e., missing data coded as non-remission). Note: BWL = behavioral weight loss; CBTgsh = cognitive-behavioral therapy via guided self-help; Med = weight-loss medication

Figure 4.. Percent weight loss for BWL (Standard) and Stepped Care throughout treatment and follow-up assessments.

Left panel shows overall percent weight loss from baseline for BWL (Standard) and Stepped Care. Right panel shows overall percent weight loss from baseline for BWL (Standard) condition and for the four arms within Stepped Care. Note: BWL = behavioral weight loss; CBTgsh = cognitive-behavioral therapy via guided self-help; Med = weight-loss medication.