Rapid response predicts binge eating and weight loss in binge eating disorder: findings from a controlled trial of orlistat with guided self-help cognitive behavioral therapy

Abstract

Objective: It is important to find ways to predict response to treatments as this may inform treatment planning. We examined rapid response in obese patients with binge eating disorder (BED) who participated in a randomized placebo-controlled study of orlistat administered with cognitive behavioral therapy delivered by guided self-help (CBTgsh) format.

Methods: Fifty patients were randomly assigned to 12-week treatments of either orlistat+CBTgsh or placebo+CBTgsh, and were followed in double-blind fashion for 3 months after treatment discontinuation. Rapid response, defined as 70% or greater reduction in binge eating by the fourth treatment week, was determined by receiver operating characteristic curves, and was then used to predict outcomes.

Results: Rapid response characterized 42% of participants, was unrelated to participants' demographic features and most baseline characteristics, and was unrelated to attrition from treatment. Participants with rapid response were more likely to achieve binge eating remission and 5% weight loss. If rapid response occurred, the level of improvement was sustained during the remaining course of treatment and the 3-month period after treatment. Participants without rapid response showed a subsequent pattern of continued improvement.

Conclusion: Rapid response demonstrated the same prognostic significance and time course for CBTgsh as previously documented for individual CBT. Among rapid responders, improvements were well sustained, and among non-rapid responders, continuing with CBTgsh (regardless of medication) led to subsequent improvements.

Figures

Figure 1. Receiver Operating Characteristic Curves Predicting Binge Remission

Receiver Operating Characteristics (ROC) curves predicting binge remission post-treatment based on percentage reduction in binge eating observed at weeks 1 to 4 and for total of weeks 1 through 4 (month 1). ROC curve for month 1 is most predictive and is in bold.

Figure 2. Receiver Operating Characteristic Curves Predicting Both Binge Remission and 5% Weight Loss

Receiver Operating Characteristics (ROC) curves predicting cases in which both binge remission and 5% weight loss occurred at post-treatment based on percentage reduction in binge eating observed at weeks 1 to 4 and for total of weeks 1 through 4 (month 1). ROC curve for month 1 is most predictive and is in bold.

Figure 3. Rapid Response and Outcomes at Post-Treatment (N=50)

Percentage of patients achieving remission from binge eating and 5% weight loss from baseline to post-treatment shown separately for patients with rapid response versus without rapid response. Data are for all randomized patients (N=50) in intent-to-treat analyses (baseline carried forward method for non-completers). Rapid response is defined as 70% or greater reduction in frequency of binge eating episodes by the fourth treatment week based on daily prospective self-monitoring. Binge remission is defined as zero binge episodes for the past month based on the Eating Disorder Examination interview.

Figure 4. Rapid Response and Outcomes at 3-Month Follow-Up (N=50)

Percentage of patients achieving remission from binge eating and 5% weight loss from baseline to three-month follow-up shown separately for patients with rapid response versus without rapid response. Data are for all randomized patients (N=50) in intent-to-treat analyses (baseline carried forward method for non-completers). Rapid response is defined as 70% or greater reduction in frequency of binge eating episodes by the fourth treatment week based on daily prospective self-monitoring. Binge remission is defined as zero binge episodes for the past month based on the Eating Disorder Examination interview.

Figure 5

Monthly frequency of binge eating by participants with rapid response versus without rapid response during the 12-week course of treatment. The data are based on daily prospective self-monitoring and are shown for treatment completers (n=39).

Figure 6

Monthly frequency of binge eating by participants with rapid response versus without rapid response at baseline, post-treatment, and again at the follow-up assessment conducted three months after completing treatments. The data are based on the Eating Disorder Examination interview and are shown for all N=50 participants (ITT with baseline carried forward).