Eating disorder outcomes: findings from a rapid review of over a decade of research

BackgroundEating disorders (ED), especially Anorexia Nervosa (AN), are internationally reported to have amongst the highest mortality and suicide rates in mental health. With limited evidence for current pharmacological and/or psychological treatments, there is a grave responsibility within health research to better understand outcomes for people with a lived experience of ED, factors and interventions that may reduce the detrimental impact of illness and to optimise recovery. This paper aims to synthesise the literature on outcomes for people with ED, including rates of remission, recovery and relapse, diagnostic crossover, and mortality.MethodsThis paper forms part of a Rapid Review series scoping the evidence for the field of ED, conducted to inform the Australian National Eating Disorders Research and Translation Strategy 2021-2031, funded and released by the Australian Government. ScienceDirect, PubMed and Ovid/MEDLINE were searched for studies published between 2009 and 2022 in English. High-level evidence such as meta-analyses, large population studies and Randomised Controlled Trials were prioritised through purposive sampling. Data from selected studies relating to outcomes for people with ED were synthesised and are disseminated in the current review.ResultsOf the over 1320 studies included in the Rapid Review, the proportion of articles focused on outcomes in ED was relatively small, under 9%. Most evidence was focused on the diagnostic categories of AN, Bulimia Nervosa and Binge Eating Disorder, with limited outcome studies in other ED diagnostic groups. Factors such as age at presentation, gender, quality of life, the presence of co-occurring psychiatric and/or medical conditions, engagement in treatment and access to relapse prevention programs were associated with outcomes across diagnoses, including mortality rates.ConclusionResults are difficult to interpret due to inconsistent study definitions of remission, recovery and relapse, lack of longer-term follow-up and the potential for diagnostic crossover. Overall, there is evidence of low rates of remission and high risk of mortality, despite evidence-based treatments, especially for AN. It is strongly recommended that research in long-term outcomes, and the factors that influence better outcomes, using more consistent variables and methodologies, is prioritised for people with ED. Plain English summaryEating disorders are complex psychiatric conditions that can seriously impact a person's physical health. Whilst they are consistently associated with high mortality rates and significant psychosocial difficulties, lack of agreement on definitions of recovery, remission and relapse, as well as variations in methodology used to assess for standardised mortality and disability burden, means clear outcomes can be difficult to report. The current review is part of a larger Rapid Review series conducted to inform the development of Australia's National Eating Disorders Research and Translation Strategy 2021-2031. A Rapid Review is designed to comprehensively summarise a body of literature in a short timeframe to guide policymaking and address urgent health concerns. This Rapid Review synthesises the current evidence-base for outcomes for people with eating disorders and identifies gaps in research and treatment to guide decision making and future clinical research. A critical overview of the scientific literature relating to outcomes in Western healthcare systems that may inform health policy and research in an Australian context is provided in this paper. This includes remission, recovery and relapse rates, diagnostic cross-over, the impact of relapse prevention programs, factors associated with outcomes, and findings related to mortality.