Premature mortality in patients with Addison's disease: a population-based study.

BACKGROUND: The survival rate of patients with primary adrenal insufficiency (Addison's disease) undergoing currently accepted replacement therapy is not known, although well-informed patients are considered to have a normal survival rate. In this study, we evaluated the mortality of patients with Addison's disease in Sweden.

METHODS: A population-based, retrospective, observational study was performed, using the National Swedish Hospital and Cause of Death Registers, covering the period from 1987-2001. After a diagnosis of Addison's disease, each patient was followed until the end of follow-up or death. Mortality was compared with that of the Swedish background population.

FINDINGS: We identified 1675 patients (995 women and 680 men) diagnosed with primary adrenal insufficiency. The average follow-up from initial diagnosis was 6.5 yr. Five hundred seven patients died during the study period compared with an expected 199. The risk ratio for all-cause mortality was 2.19 (confidence interval 1.91-2.51) for men and 2.86 (confidence interval 2.54-3.20) for women. The excess mortality in both men and women was attributed to cardiovascular, malignant, and infectious diseases. Concomitant diabetes mellitus was observed in 12% of the patients, but only contributed to the increased mortality to a minor extent.

INTERPRETATION: Compared with the background population, we observed that the risk ratio for death was more than 2-fold higher in patients with Addison's disease. Cardiovascular, malignant, and infectious diseases were responsible for the higher mortality rate.