Association of obesity with cerebral microbleeds in neurologically asymptomatic elderly subjects

Obesity is associated with an increased risk of cardiovascular disease, but few studies have investigated the effects of obesity on subclinical cerebrovascular disease. Cerebral microbleeds (CMBs) are radiological markers of cerebral small vessel disease and reflect underlying vasculopathy. In this context, we assessed whether obesity was related to CMBs and to CMB subtypes categorized by location. Neurologically asymptomatic elderly subjects (n = 1,251; age ≥ 65 years) who visited for routine health check-ups were included in this study. Cerebral microbleeds were evaluated through T2*-weighted gradient-recalled echo MRI. The subjects were categorized into two groups depending on CMB location: strictly lobar and deep or infratentorial microbleeds. Body mass index was calculated, and obesity was defined using the World Health Organization Western Pacific Regional Office criteria. A total of 120 (9.6 %) subjects were found to have CMBs. As the severity of obesity increased, the prevalence of CMBs increased. Compared with the normal weight group and after controlling possible confounders, the risk of deep or infratentorial microbleeds was significantly increased in the overweight group [odds ratio (OR) 2.32, 95 % confidence interval (CI) 1.19-4.53], and the obese group (OR 2.17, 95 % CI 1.14-4.13). However, the ORs for the strictly lobar microbleeds were not increased in either the overweight or obese groups. Obesity was associated with deep or infratentorial microbleeds. This finding suggests that obesity affects cerebral small vessels through arteriosclerotic vasculopathy. Based on our findings, we postulate that obesity is associated with the presence of subclinical and bleeding-prone cerebrovascular disease in the elderly.