Risk factors for silent cerebral infarction in the elderly

BACKGROUND: A silent cerebral infarction (SCI) is often found in the elderly. However, studies on SCIs focusing on an elderly population are sparse. Our objective was to evaluate risk factors of SCIs in healthy elderly individuals. METHODS: One hundred seventy-five neurologically normal community-dwelling Japanese people aged >/=65 years (128 men and 47 women; 77.5 +/- 8.7 years) were studied. Among them we assessed the demographic data and detected SCIs on brain magnetic resonance imaging scans. RESULTS: Eighty four subjects had at least one SCI. Hypertension and low body mass index (BMI) were the significant risks for SCIs in multivariate analysis adjusted for age, sex and other risk factors. Mean BMI in subjects with SCIs was significantly lower than those without SCIs (20.8 +/- 3.2 kg/m(2) vs. 22.1 +/- 3.2 kg/m(2)). In the subgroup analysis by age stratum regarding hypertension and BMI, hypertension was a significant risk factor in subjects aged 65-75 years. Lower BMI had a significant risk in subjects aged >/=81 years. CONCLUSIONS: Hypertension and increasing age have been recognized as risk factors for SCIs, and low BMI might be a significant risk especially in superelderly subjects. Further data with a larger sample size is needed to confirm the relationship between BMI and SCIs among the elderly.