[Role of abdominal obesity in asymptomatic intracranial arterial stenosis: a community-based study]

To investigate the relationship between abdominal obesity and intracranial artery stenosis and the underlying mechanism.

By cluster sampling, 1405 adult Han people were selected from the residential communities. Among them, 1035 people conformed to the inclusion criteria. Medical history was documented and body height, body weight, waist circumference, hip circumference and blood pressure were measured. Venous blood samples were collected to detect the serum concentrations of fasting glucose, total cholesterol and triglycerides. Serum nitric oxide (NO) level was determined by cadmium reduction method. Middle cerebral artery stenosis (MCAS) was diagnosed by transcranial Doppler. The SPSS 11.0 software package was used for data analysis.

MCA stenosis was found in 66 subjects (6.4%). Univariate analysis showed history of hypertension, history of ischemic heart disease, systolic blood pressure and diastolic blood pressure were the risk factors for MCAS and waist-to-hip ratio (WHR) was a risk factor only in males. Logistic regression demonstrated history of hypertension was an independent risk factor for MCAS both in males and females (P = 0.011, P = 0.009) and WHR for MCAS only in males (P = 0.030). Among males and females over 55 years old, the NO levels were higher in people with a higher WHR and the difference was statistically significant (P = 0.042, P = 0.016); however the NO levels for people with a varying WHR showed statistically insignificant difference among females under 55 years old (P = 0.228).

Hypertension and abdominal obesity are important risk factors for MCAS. Endothelial cell dysfunction and an elevated level of oxidative stress may be involved in the atherogenetic mechanism of abdominal obesity while estrogen may play a protective role in it.