Premature Mortality in Patients With Anorexia Nervosa: A Matched Cohort Study of Cause of Death

Abstract

Objective

To determine the extent to which anorexia nervosa is associated with premature mortality.

Method

We carried out a matched cohort study of 7332 male and female patients with anorexia nervosa and 73,215 patient controls who were admitted between 1989 and 2023 in hospital centers of Quebec, Canada. We tracked the patients longitudinally over time to identify premature deaths before age 75 years and determined the cause of death. We used stratified Cox regression models adjusted for patient characteristics to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between anorexia nervosa and premature mortality.

Results

Overall, 186 (2.5%) patients with anorexia nervosa and 615 (0.8%) matched controls died before age 75 years. Compared with no anorexia, anorexia nervosa was associated with 3.02 times the risk of premature mortality among females (95% CI 2.50–3.65) and 2.23 times the risk among males (95% CI 1.35–3.70). Patients with a first anorexia nervosa admission between age 20 and 29 years were most at risk of premature mortality (HR 8.00, 95% CI 4.30–14.88), as were patients hospitalized ≥ 3 times for anorexia nervosa (HR 4.72, 95% CI 3.25–6.84). Anorexia nervosa was associated with premature mortality due to metabolic and other endocrine disorders, suicide, and a range of other causes.

Discussion

Anorexia nervosa is associated with an elevated risk of premature mortality from metabolic disorders, suicide, and other causes. Patients who are female, hospitalized as young adults, or have repeated admissions for anorexia nervosa are most at risk.