Prevalence and risk factors for depression in non-demented primary care attenders aged 75 years and older.

BACKGROUND: Depression among the elderly is an important public health issue. The aims of this study were to report the prevalence of depression and to determine the impact of socio-demographic variables, functional impairment and medical diagnoses, lifestyle factors, and mild cognitive impairment on depression as part of the German Study on Ageing, Cognition and Dementia in Primary Care Patients (AgeCoDe Study).
METHODS: Included in the cross-sectional survey were 3327 non-demented subjects aged 75 and over attending general practitioners (GPs) (n=138) in an urban area of Germany. The GDS-15 Geriatric Depression Scale was used to measure depression with a threshold of <6/6+. Associations with social and clinical risk factors were assessed by means of multiple logistic regression models.
RESULTS: The prevalence of depression was 9.7% (95% confidence interval 8.7-10.7). In a univariate analysis, the following variables were significantly associated with depression: female gender, increasing age, living alone, divorce, lower educational status, functional impairment, comorbid somatic disorder, mild cognitive impairment, smoking, and abstinence from alcohol. After full adjustment for confounding variables, odds ratios for depression were significantly higher only for functional impairment, smoking, and multi-domain mild cognitive impairment. LIMITATIONS: Recruitment procedures might have led to an underestimation of current prevalence. The cross-sectional data did not allow us to analyze the temporal relationship between risk factors and depression.
CONCLUSIONS: The prevalence of depression in the elderly is high and remains high into old age. In designing prevention programs, it is important to call more attention to the impact of functional and cognitive impairment on depression.