Excess mortality associated with eating disorders : a population-based cohort study.

Background Individuals with eating disorders (EDs) have a high mortality risk. Few population-based studies have estimated mortality risk in EDs other than anorexia nervosa. Aims To investigate all-cause mortality within a population-based cohort of individuals who received hospital-based care for any ED (anorexia nervosa, bulimia nervosa or ED not otherwise specified) in Ontario, Canada. Methods We conducted a retrospective-cohort study of 19,041 individuals with an ED from January 1, 1990, to December 31, 2013 using administrative healthcare data. The outcome of interest was death. Excess mortality was assessed using standardized mortality ratios (SMRs) and potential years of life lost (PYLL). Cox proportional hazards regression models were used to examine socio-demographic and medical comorbidities associated with greater mortality risk. Results The ED cohort had 17,108 females (89.9%) and 1,933 males (10.1%). The all-cause mortality for the entire ED cohort was five times higher than expected compared to the Ontario population (SMR = 5.06; 95% CI:4.82-5.30). SMRs were higher for males (SMR=7.24; 95% CI: 6.58- 7.96) relative to females (SMR=4.59; 95% CI: 4.34-4.85), overall and in all age groups in the cohort. For both sexes, the ED cohort PYLL was more than 6 times higher than the expected PYLL in the Ontario population. Conclusions and Relevance Patients with EDs experience five to seven times higher mortality rates compared to the overall population. There is an urgent need to understand the mortality risk factors to improve health outcomes among individuals with eating disorders.