The prevalence of stroke and the association between stroke and depression among a very old population.

There are few studies comparing those who have had and have not had a stroke among those aged 80 years and over, the very old. The aim of this paper was to investigate the prevalence of stroke and the association between stroke and depression in a very old population. This paper is based on cross-sectional data from a population-based study performed between 2005 and 2007. Half of those aged 85 years, all 90-, and 95-year-olds and older in eight urban and rural municipalities in northern Sweden and Finland were invited to participate. A sample of 601 individuals who participated fully in the study was selected. Data were collected through assessments, structured interviews and investigation of medical charts. A specialist in geriatric medicine determined disease status for depression based on medical records and results from the Geriatric Depression Scale (GDS)-15, the Montgomery Åsberg Depression Rating Scale (MADRS) and the Organic Brain Syndrome (OBS) scale, and for stroke based on medical records and reported disease. The prevalence of stroke was 21.5%. The prevalence of depression was 50.4% among those with stroke compared to 34.3% among those without stroke (OR 1.944, p<0.001). In a logistic regression model adjusted for several demographic variables, diseases and functional level, stroke was independently associated with depression (OR 1.644, p=0.038). A large proportion of those with depression, both with and without stroke, were not receiving antidepressant medication. In conclusion, the stroke prevalence was high and stroke showed a strong association with depression among very old people.