Temporal patterns of recovery across eating disorder subtypes

Objective: To compare patterns of recovery in individuals with index episodes of anorexia nervosa (AN) and bulimia nervosa (BN). Method: Using Kaplan-Meier methods and Cox proportional hazards models, comparisons were conducted that were conditional on duration of eating disorder from onset and included a conservative recovery criterion of 3 asymptomatic years. Data collection was retrospective and from two of the international Price Foundation genetic studies on 901 individuals with eating disorders. Results: Using Kaplan-Meier methods, 11% of those with index AN and 10% of those with index BN met recovery criteria at 10 years. At 15 years, 16% of those with index AN and 25% of those with index BN met recovery criteria. In a Cox proportional hazards model the index BN group had three times the rate of recovery at 10-14 years (p = 0.01) than the index AN group. Conclusions: Initially the probability of recovery was greater for those with index AN, but as the duration of the eating disorder lengthened those with BN had higher probabilities of recovery. Replication of these results with prospective data using similarly stringent recovery criteria and methods is required to confirm trends.