Epidemiology of depression in old age – results of the Leipzig Longitudinal Study of the Aged (LEILA 75+)

Background: Depression is one of the most common mental disorders in old age. In order to assess future needs of the health care system for prevention and treatment, information on epidemiology of depression among the highest age groups is re-quired. However, most previous studies just focused on prevalence and incidence rates of late life depression across the entire old age. Methods: For a population-based sample of 1,265 elderly individuals aged 75 years and older, prevalence and incidence rates as well as risk factors of depression were determined. Individuals were requested every 1.5 years over six waves. Depression was assessed dimen-sionally by the CES-D (Center of Epidemiologic Studies Depression Scale) and cate-gorically by the SCID (Structured Clinical Interview for DSM-IV). Results: The preva-lence rates were 1.0% for Major Depression, 2.5% for Minor Depression and 14.3% for subsyndromal depression. The rates increased for Minor and subsyndromal de-pression with rising age. Risk factors for depression were female gender, lack of so-cial support, and stressful life events. The incidence rates were 6.9 per 1000 person-years for Major Depression, 16.6 per 1000 person-years for Minor Depression and 33.9 per 1000 person-years for subsyndromal depression. Conclusion: Research findings suggest that latest-life depression may occur on a spectrum ranging from very mild subsyndromal forms to major depression, with the highest rates for subsyn-dromal forms. The future demographic change will lead to an increase in the burden of depression in old age. Therefore health policy should promote the development and use of effective treatment strategies.