Serum Lipid Fractions and Cerebral Microbleeds in a Healthy Japanese Population.

BACKGROUND: Cerebral microbleeds (CMBs) are associated with focal hemosiderin deposits and represent a form of cerebral small vessel disease. To date, indefinite and inconsistent reports are available regarding the association between serum lipid fractions and CMBs. In addition, these previous studies did not include Asian populations, who may have a higher risk of cerebral hemorrhage. The purpose of this study was to examine the associations between serum lipid fractions and CMBs in healthy Japanese subjects.

METHODS: We performed a cross-sectional study involving 4,024 neurologically normal Japanese subjects (mean age 61.6 years). All the participants underwent 1.5-Tesla magnetic resonance imaging scan, and CMBs were classified into 3 groups based on their locations. The concentrations of lipid fractions were categorized into quartiles and the association between the lipid fractions and CMBs were investigated using logistic regression analysis.

RESULTS: CMBs were observed in 164 (4.1%) of participants. Of these participants with CMBs, 33 (20.1%) had lobar CMBs and 91 (55.5%) had deep CMBs. Subjects with deep CMBs had lower total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C) levels. After adjusting for confounding factors, lower TC and HDL-C levels were still associated with the presence of deep CMBs (OR for the highest vs. the lowest quartiles of TC and HDL-C was 2.28 [95% CI 1.05-4.94], and 1.93 [95% CI 1.02-3.65], respectively). The presence of subcortical infarcts and periventricular hyperintensities was more frequently observed in deep CMBs, whereas white matter hyperintensities were more frequently observed in lobar CMBs.

CONCLUSIONS: Our results suggest that low serum TC and HDL-C levels are closely associated with deep CMBs.