Background: Anorexia nervosa is a mental disorder with high mortality.
Aims: To estimate standardised mortality ratios (SMRs) and to investigate potential prognostic factors.
Method: Six thousand and nine women who had in-patient treatment for anorexia nervosa were followed-up retrospectively using Swedish registers.
Results: The overall SMR for anorexia nervosa was 6.2 (95% CI 5.5-7.0). Anorexia nervosa, psychoactive substance use and suicide had the highest SMR. The SMR was significantly increased for almost all natural and unnatural causes of death. The SMR 20 years or more after the first hospitalisation remained significantly high. Lower mortality was found during the last two decades. Younger age and longer hospital stay at first hospitalisation was associated with better outcome, and psychiatric and somatic comorbidity worsened the outcome.
Conclusions: Anorexia nervosa is characterised by high lifetime mortality from both natural and unnatural causes. Assessment and treatment of psychiatric comorbidity, especially alcohol misuse, may be a pathway to better long-term outcome.