Cardiovascular risk factors for and prevalence of silent brain infarcts in the elderly: the Rotterdam Scan Study
Background Silent brain infarcts are commonly seen on MRI in patients with a first stroke, and in healthy elderly as well. They seem to be associated with an increased risk of stroke. It is unclear whether risk factors for silent infarcts are identical to those for symptomatic stroke. We investigated the prevalence of and cardiovascular risk factors for silent brain infarcts. Methods The Rotterdam Scan Study is a population based cohort study among 1077 participants, aged 60–90 years. All participants underwent cerebral MRI. Infarcts were scored blind to history of stroke and TIA. We assessed cardiovascular risk factors by interview and physical examination. We analysed the associations between risk factors and presence of infarcts by logistic regression, adjusted for age, sex and relevant confounders. Results In 262 participants (24%) infarcts showed on MRI. Of them, 216 persons had silent and 46 symptomatic infarcts. Prevalence of both silent and symptomatic infarcts increased with age (OR 1.08 per year (95%CI 1.06–1.10) and 1.08 (1.03–1.12), respectively). Silent infarcts were more frequent in women than men (OR 1.4 (1.0–1.9)). We found no sex difference for symptomatic infarcts. Hypertension was associated with silent infarcts (OR 2.3 (1.6–3.2)), as was pulse pressure (OR 1.2 per 10 mm Hg increase (1.1–1.3)). Diabetes mellitus, smoking and myocardial infarction tripled the odds only of symptomatic infarcts. Conclusions Prevalence of silent brain infarcts is higher with increasing age and in women. Hypertension and high pulse pressure are associated with silent infarcts. Other cardiovascular risk factors are related only to symptomatic infarcts.