Increasing prevalence of Addison's disease in German females: health insurance data 2008–2012

Abstract
Objective: Our objective was to investigate the epidemiology of autoimmune Addison's disease (AD) in Germany. Design: Routine data were analyzed from the Statutory Health Insurance (SHI) database of the Techniker Krankenkasse (TK) for an observation period from 01/01/2008 to 31/12/2012. The TK is one of the largest German health care insurance providers covering more than 10% of the German population. Subjects and methods: Between 2008 and 2012 a total of 2477 diagnoses of primary adrenal failure were recorded in the SHI database. After exclusion of secondary iatrogenic or other non-idiopathic forms and after adjustment for incomplete data sets 1364 diagnoses of autoimmune-mediated AD remained. Results: The prevalence of AD in our cohort showed a steady increase from 82 per million in 2008 to 87 per million in 2012. On average the prevalence rose about 1.8% per year and due to a pronounced increase (2.7%) in females. The prevalence was lower in men (63-68 per million) than in women (96-108 per million). Autoimmune comorbidities were found in 46.5% of AD patients. Adrenal crises were documented with a frequency of 14-17/100 patient years. Conclusions: These data provide a first epidemiological profile of this rare and perilous endocrine disease in Germany. Although the prevalence of AD appears lower than in the Scandinavian countries the increasing figures in females over the last 5 years warrant further investigations. Furthermore adrenal crises pose a considerable burden. Hereby we can show that health insurance data provide a valuable tool for epidemiological studies in the absence of national registries.