The Prevalence and Risk Factors of Cerebral Microbleeds: A Community-Based Study in China

Introduction: Cerebral microbleeds (CMBs) are frequently found in the healthy elderly. However, data on the prevalence and risk factors of CMBs in the general population of China are lacking. Methods: A cross-sectional study focusing on the prevalence and risk factors of CMBs was conducted in stroke-free elderly from Shanghai Wuliqiao community. MRI was performed at 3Tesla and cardiovascular risk factors (eg, age, smoking history, and hypertension), cerebral small vessel disease (CSVD) markers (eg, white matter hyperintensities, lacunar infarction, and enlarged perivascular space) and genetic information (eg, APOE, CR1) were recorded. Poisson regression was used to analyze the risk factors of the presence and location of microbleeds. Results: A total of 199 participants (70.8 +/- 7.2 years old; male 31.2%) were finally included in our analysis. The overall prevalence of CMBs was 12.6% (25/199) and increased with age from 7.5% (55-64 years old) to 19.3% (over 75 years old). Of those with CMBs, most of them (16/25) located in the deep/mixed region and had 1-2 CMBs (18/25). Poisson regression analysis showed that white matter hyperintensities (OR=1.22, 95% CI: 1.16-1.29), APOE epsilon 4+ carrier (OR=2.16, 95% CI: 1.18-3.96) and CR1 non-F/F isoform (OR=7.78, 95% CI: 4.34-13.96) were associated with CMBs. Further analysis found that in addition to the above three risk factors, hypertension (OR=2.98, 95% CI: 1.16-7.64), lacunar infarction (OR=2.39, 95% CI: 1.19-4.81) also increased the risk of deep/mixed CMBs. Conclusion: The prevalence of cerebral microbleeds is similar to other countries. Cardiovascular risk factors, CSVD markers, and genetic factors (APOE epsilon 4, CR1 non-F/F isoform) were associated with CMBs, suggesting an interaction of multiple pathogenesis in Chinese stroke-free community population.