Gender differences in blood lipids and the risk of ischemic stroke among the hypertensive adults in rural China

Background: Though large epidemiological studies have not established associations between blood lipids and ischemic stroke, increasing evidences have suggested that lipid-modifying agents may reduce cerebrovascular events. Aims: To determine whether blood lipids are risk factors for ischemic stroke among hypertensive rural adults in China. Settings and Design: A cross-sectional survey was conducted during 2004-2006, which underwent cluster multistage sampling to a hypertensive resident group in the countryside of China. Materials and Methods: A total of 6,412 individuals (2,805 men, 3,607 women) with age ≥ 35 years were included. At baseline, lifestyle and other factors were obtained and blood lipids were assessed at a central study laboratory. Ischemic stroke was defined according to the criteria established by the National Survey of Stroke and all cases were further classified into lacunar infarction and other ischemic strokes. Statistical Analysis: Univariable and multivariable logistic regression were used. Results: In the univariable logistic regression model, LDL cholesterol (LDLc) in men and total cholesterol (TC), LDLc and TC-to-HDL cholesterol (TC: HDLc ratio) in women were risk factors for other ischemic strokes, with OR 1.42 (95% CI , 1.16-1.75), 1.31 (95% CI , 1.11-1.55), 1.47 (95% CI , 1.16-1.88) and 1.67 (95% CI , 1.28-2.14), respectively. After adjusting for independent variables, an increase in non-HDL cholesterol (non-HDLc) was associated with a significant increased risk of other ischemic strokes in women, with adjusted OR 1.45 (95% CI, 1.08-1.93). Conclusions: LDLc was the common risk factor for ischemic stroke in men and women, whereas Non-HDLc, TC and TC: HDLc ratio levels were related to ischemic stroke as risk factors only in women.