Cognitive decline in a prospectively studied group of stroke survivors, with a particular emphasis on the >75's.

BACKGROUND Although cognitive decline is frequent after stroke, there has been very little work focussing upon older age groups, in whom the majority of strokes occur. OBJECTIVE To determine whether cognitive decline is more common in older (>75) compared to younger (<75) stroke survivors. METHOD A cohort of 360 stroke survivors of all ages from a stroke register in Newcastle, UK, were assessed prospectively at 3 time points over 1 year with a standardized battery. Dementia was diagnosed according to Diagnostic and Statistical Manual of Mental Disorders, fourth edition criteria. RESULTS The overall one year prevalence of dementia was 23%, but rose from 7% in the under 65's to 53% in over 85's. People over 75 were significantly more likely to have dementia (Odds Ratio 8.9, 95% Confidence Intervals 4.1-19.1). CONCLUSION The striking age related increase in the prevalence of dementia has important implications for service planning and clinical management.