Depression in elderly patients with Alzheimer dementia or vascular dementia and its infl uence on their quality of life

Abstract
Background: Alzheimer dementia (AD) and vascular dementia (VD) are the most common causes of dementia in the elderly. Depression is an important co-morbid disorder in these diseases, which is often challenging to recognize. We investigated the prevalence of depression in patients with AD and VD and estimated the influence of depression on the health-related quality of life (HrQoL) in these patients. Materials and Methods: We evaluated prevalence of depression in consecutively recruited patients with AD or VD (n= 98). Depression was diagnosed according to criteria of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) and scored using the Geriatric Depression Scale. The EuroQol (EQ-5D and visual analogue scale) was applied to evaluate HrQoL. The severity of cognitive impairment was measured by the Mini-Mental State Examination (MMSE). Multiple regression analysis was used to identify factors predicting severity of depression. Results: The prevalence of depression in AD/VD was 87%. In comparison to the general population, HrQoL measured on the visual analogue scale was reduced by 54% in patients with AD/VD. In the dimension "anxiety/depression" of the EQ-5D, 81% of patients with AD/VD had moderate or severe problems. Depression showed significant association with reduced HrQoL (P<0.01). Independent predictors of more severe depression were older age, male gender, better MMSE scores and being not married. Conclusions: Depression is a prevalent psychiatric co-morbidity in patients with AD/VD, which is often under-diagnosed being masked by cognitive impairment. Depression is a predictor of reduced HrQoL in elder people with AD/VD. Therefore, they should be screened for presence of depressive symptoms and receive adequate antidepressant treatment.