An overview and investigation of relapse predictors in anorexia nervosa: A systematic review and meta-analysis

An extensive number of predictors has been examined across the literature to improve knowledge of relapse in anorexia nervosa (AN). These studies provide various recovery and relapse definitions, follow-up durations and relapse rates. The current study summarizes these values and predictors of relapse in AN in a review and meta-analysis.

The study was executed according to PRISMA guidelines. Different databases were searched and studies in which participants did not receive an official clinical diagnosis were excluded. A quality analysis was performed using the National Institute of Health's Study Quality Assessment Tool. Random-effects meta-analyses were conducted to summarize data.

Definitions of relapse and recovery were diverse. During an average follow-up period of 31 months an average relapse rate of 37% was found. Predictive variables from 28 studies were grouped in six categories: age and sex, symptoms and behaviors, AN subtype and duration, weight or weight change, comorbidity, and personality. The studies were characterized by non-significant and contradictory results. Meta-analyses were performed for the predictors age, AN duration, pre-treatment BMI, post-treatment BMI and depression. These yielded significant effects for post-treatment BMI and depression: higher pre-treatment depression (SMD = .40 CI [.21-.59] and lower post-treatment BMI (SMD = -.35 CI [-.63 to -.07]) increased relapse chances in AN.

Our results emphasized a lack of sufficiently powered studies, consistent results, and robust findings. Solely post-treatment BMI and pre-treatment depression predicted relapse. Future research should use uniform definitions, larger samples and better designs, to improve our understanding of relapse in AN.

Knowledge about predictors is important to understand high relapse rates. Our study performed a review and meta-analysis of relapse predictors in AN. Related to the heterogeneity in studies examining predictors, an overview of relapse and recovery definitions, follow-up durations and relapse rates for AN was provided. Significant effects were found for post-treatment BMI and pre-treatment depression. More studies with uniform definitions are needed to improve clinical implications.