Postdischarge Mortality in a Cohort Hospitalized With Anorexia Nervosa

To characterize mortality after hospital discharge in cohorts with and without anorexia nervosa (AN).

We obtained data for all hospitalizations for psychiatric reasons in Canada (except Quebec) between April 1, 2006, and March 31, 2021 (n = 1.3 million admissions). Cases of AN were identified using ICD-10 (F50.0 and F50.1) codes. First admissions during this interval for AN and other psychiatric conditions were linked to vital statistics data. Mortality was characterized through cross-tabulation, Cox proportional hazards models, and competing cause regression.

After adjustment for age and sex, there was no significant difference in mortality between AN and those with other psychiatric conditions (HR = 1.04; p = 0.644). Among AN admissions, 25% (95% CI 18.6-31.4) of deaths were attributed to psychiatric conditions (ICD-F codes), with 88% of these (comprising 22% of all deaths in the AN group) having AN itself identified as the underlying cause of death. In contrast, only 8% of deaths among non-AN admissions were attributed to a mental disorder.

Prevention of premature mortality in the general psychiatric population emphasizes modification of metabolic (e.g., hyperlipidemia) and lifestyle-related (e.g., sedentary behavior) risk factors. However, as AN itself makes a major contribution to mortality, specialized preventive strategies may be required.