Risk factors for cerebrovascular disease as correlates of cognitive function in a stroke-free cohort

We investigated the relationship between risk factors for cerebrovascular disease and cognitive function in 249 stroke-free community volunteers (age, 70.8 +/- 6.7 years; education, 12.3 +/- 4.6 years) who were given tests of memory, language, visuospatial, abstract reasoning, and attentional skills. Using logistic regression analyses, we examined hypertension, diabetes mellitus, myocardial infarction, angina, hypercholesterolemia, and cigarette smoking as potential correlates of performance within these cognitive domains. Controlling for demographic factors within the logistic models, diabetes mellitus was a significant independent correlate of abstract reasoning deficits (odds ratio, 10.9; 95% confidence interval, 2.2 to 54.9) and visuospatial dysfunction (odds ratio, 3.5; confidence interval, 1.2 to 10.7), while hypercholesterolemia was a significant independent correlate of memory dysfunction (odds ratio, 3.0; confidence interval, 1.4 to 6.6). Prolonged exposure to vascular risk factors such as diabetes mellitus and hypercholesterolemia may lead to atherosclerotic disease, possibly resulting in "silent" infarctions or impaired cerebral blood flow and a decline in cognitive functioning.