Prevalence and risk factors of asymptomatic intracranial arterial stenosis in a community-based population of Chinese adults

Background and purpose: Intracranial arterial stenosis (ICAS) is one of the most common causes of ischaemic stroke in Asia. Knowledge of the prevalence and risk factors of asymptomatic ICAS is limited. The prevalence of ICAS was therefore investigated and its risk factors in a Chinese community-based population were explored.

Methods: From 2010 to 2011, a stratified (by sex and age) random sample of 5440 participants aged 40 years or older were enrolled in the study. ICAS was assessed using transcranial Doppler. Logistic regression was used to evaluate potential risk factors associated with ICAS in participants.

Results: In total, 13.2% (95% CI 12.3-14.1) of the subjects had ICAS, and women were more likely than men to have ICAS in the 40-49 year age group. Hypertension [odds ratio (OR) = 2.23, 95% CI 1.87-2.66], diabetes (OR = 1.99, 95% CI 1.62-2.45), left ventricular hypertrophy (OR = 1.66, 95% CI 1.18-2.34) and elevated high-sensitivity C-reactive protein (OR = 1.55, 95% CI 1.19-2.02) were independently associated with higher prevalence of ICAS after adjusting for age, gender, body mass index, smoking status and other covariates. Of the 716 ICAS individuals, 90.6% had one or more of these risk factors. Amongst the subjects who had at least one risk factor, 15.2% had ICAS.

Conclusions: Intracranial artery stenosis is common in the Chinese population. Individuals who had one or more risk factors were more likely to have ICAS, suggesting more aggressive risk factor management.