Prevalence and cardiovascular risk factors of asymptomatic intracranial arterial stenosis: The Kongcun Town Study in Shandong, China.

BACKGROUND AND PURPOSE: This study was to investigate the prevalence and cardiovascular risk factors (CRFs) of asymptomatic intracranial atherosclerotic stenosis (aICAS) amongst middle-aged and older adults living in rural communities in China. METHODS: This population-based study included 2019 subjects (aged >/=40 years, 52.3% women) who were free of stroke and living in rural communities in China. From October 2017 to May 2018, data on demographics, CRFs and health conditions were collected through face-to-face interviews, physical examination and laboratory tests. Asymptomatic ICAS was detected through a two-phase procedure: a screening phase with transcranial Doppler ultrasound, followed by a diagnostic phase with magnetic resonance angiography examination. Multivariable logistic regression models were used to analyse CRFs associated with aICAS. RESULTS: Of the 2019 participants, aICAS was detected in 153 persons. The overall prevalence of aICAS was 7.6%, and the prevalence of moderate-to-severe aICAS was 5.0%. The multi-adjusted odds ratio (95% confidence interval) of aICAS associated with CRFs was 2.40 (1.56-3.69) for hypertension, 1.91 (1.32-2.76) for high hypersensitive C-reactive protein, 1.68 (1.14-2.49) for diabetes and 1.61 (1.08-2.41) for overweight or obesity. When these four CRFs were aggregated, compared with participants without any of these factors, the multi-adjusted odds ratios (95% confidence interval) of aICAS for persons concurrently having one, two and three or more of these factors were 1.14 (0.52-2.48), 2.91 (1.42-5.99) and 5.51 (2.64-11.50), respectively (P for linear trend <0.001). CONCLUSIONS: Asymptomatic ICAS is common amongst rural-dwelling middle-aged and older Chinese people. Hypertension, diabetes, overweight or obesity and high hypersensitive C-reactive protein, especially when coexisting, are strongly associated with aICAS.