Association of conventional risk factors for cardiovascular disease with IMT in middle-aged and elderly Chinese

To study the association between known risk factors for cardiovascular disease and intima-media thickness (IMT) in the carotid and popliteal arteries in middle-aged and elderly Chinese adults. 686 middle aged and elderly Chinese adults from the China Da Qing Diabetes Prevention Study who had full clinical, laboratory, ultrasound examination results were enrolled in the study. Common carotid artery (CCA) and popliteal artery (PA) IMT were obtained using high resolution ultrasound machine. Pearson's or Spearman's correlation analysis and logistic regression analysis were used to determine association between risk factors [age, gender, tobacco smoking, body mass index (BMI), diabetes mellitus (DM), systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol, total triglyceride, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol, glycosylated hemoglobin (HbA(1c))] and CCA- or PA-IMT. The age range of the study population was 45-87 years, 384 of them (56 %) were women. The prevalence of high blood pressure and DM was 60.6 and 68.8 %, respectively. Participants in DM group tended to be older, had greater value for SBP, HbA(1c) and PA-IMT, but smaller value for DBP than those in control group. Smoke status, BMI, blood lipids and CCA-IMT were not statistically different between groups. Pearson's or Spearman's rank correlation analysis showed that CCA-IMT had a positive correlation with age, gender, DM, SBP, BMI and HbA(1c), negative correlation with HDL-C. PA-IMT showed a positive correlation with age, gender and SBP. Univariate logistic regression analysis showed that elevation of age, SBP, BMI, HbA(1c) and having DM were significant predictors of CCA-IMT thickening, so was reduction of HDL-C. Risk factors that predicted significant thickening of PA-IMT were age, gender, tobacco smoking. After adjusted for age and gender, except HDL-C, the other four risk factors (SBP, BMI, HbA(1c) and having DM) that predicted CCA-IMT thickening remained significant; however none of the risk factors predicted PA-IMT thickening after adjusted for age and gender. The current results provide evidence that CCA-IMT is a superior marker for atherosclerosis compared with PA-IMT. Aggressive control of SBP, HbA(1c) and proper control of weight may postpone thickening of CCA-IMT.