Endocrine Abstracts

Background: The prevalence of type 1 diabetes mellitus (DM) among patients with primary adrenal insufficiency (Addison’s disease) is 3-4 times higher than the expected prevalence in the population. The mortality rate due to DM is more than 3-fold the mortality rate in the background population. The impact of DM on mortality rate in patients with Addison’s disease is not known.

Objectives: To study the frequency of DM and its impact on mortality rate in patients with Addison’s disease.

Study design: In a population-based retrospective observational study between the years 1987 and 2001 using the Swedish Hospital Register we followed patients from the first registered hospitalisation where the diagnosis of Addison’s disease appeared until end of follow-up or death. We looked for the concomitant presence of DM at the time of detection.

Results: We identified 1675 patients, 995 women and 680 men, diagnosed with primary adrenal insufficiency. Concomitant DM was observed in 199 (12%) of the identified patients. DM had a significant influence on total mortality with the relative risk (RR) for death 1.82 (CI 1.29–2.06) for men and 1.52 (CI 1.11–2.07) for women with Addison’s disease and DM compared with those patients with Addison’s disease without DM.

The impact of DM on the excess mortality in the whole group of Addison’s patients was limited since excluding patients with concomitant DM only decreased the RR for death by 7% in both men (2.19 vs 2.04) and women (2.86 vs. 2.68).

Conclusions: Having DM and Addison’s disease significantly increased the risk of death when compared with having Addison’s disease alone. However, the overall impact of concomitant DM on the total mortality in all patients with Addison’s disease was minor.