Defining Recovery and Relapse in Bulimia Nervosa: A Systematic Review of the Literature.

Objective: Despite advances in understanding bulimia nervosa (BN), standardized definitions of outcome stages remain lacking. This review aims to synthesise definitions of recovery and relapse in BN to improve its assessment and comparability across study outcomes.

Methods: A systematic review was conducted using PRISMA guidelines. PubMed and PsycINFO were searched (October 2024) combining keywords 'recovery', 'remission' or 'relapse' with 'bulimia nervosa'.

Results: N = 76 studies were included. Recovery was most commonly defined using diagnostic (n = 30, 53%; For example, a Psychiatric Status Rating score ≤ 2 and absence of a DSM-based diagnosis) or behavioural criteria (n = 28, 49%; typically binge eating and compensatory behaviours assessed with the Eating Disorder Examination interview/questionnaire; EDE/EDE-Q). Fewer studies considered medical/physical (n = 17, 30%; That is, Body Mass Index ≥ 18.5) or psychological criteria (n = 10, 18%; For example, EDE/EDE-Q global or all subscales score within 1SD of community norms). N = 11 (14%) addressed partial recovery as a period of symptomatic improvement with residual symptoms. Relapse was defined using behavioural criteria (n = 18, 25%; That is, re-emergence of binge eating and compensatory behaviours) or meeting DSM-based diagnostic criteria after remission (n = 10, 14%).

Conclusions: Adopting multidimensional definitions of recovery and relapse, incorporating the most endorsed behavioural, diagnostic, medical/physical, and psychological criteria, may increase diagnostic accuracy, facilitate assessment and outcomes comparability.