ABSTRACT
PURPOSE: Elevated circulating oxidized low density lipoprotein (Ox-LDL) levels are associated with increased risk of atherosclerosis, which may be due to high plasma homocysteine (Hcy) and low intakes of antioxidants. We investigated the contribution of dietary intakes of antioxidants to Hcy-induced LDL oxidation in atherosclerotic patients (AP) and controls. MATERIALS AND METHODS: Male AP (n = 101) who were confirmed by coronary angiography and 91 controls were evaluated by blood biochemistry and dietary intakes. To determine whether homocysteine is an independent risk factor for atherosclerosis, subjects were divided into three groups; low- ( or = 12.1 uM/L) Hcy. RESULTS: Plasm levels of homocysteine and LDL were higher, but plasma apo A-I in HDL and folate were lower in the AP group. The odds ratio (OR) for the risk of atherosclerosis was 3.002 [95% confidence interval (CI), 1.27-7.09] for patients in the highest tertile with homocysteine > or = 12.1 uM/L. AP having high homocysteine levels had low intakes of vitamin A, beta-carotene and vitamin C. By logistic regression analysis, age, body mass index (BMI), plasma LDL, plasma folate, and low intakes of vitamin A and beta-carotene were found to be risk factors for atherosclerosis in patients with high-Hcy, but dietary B vitamins including folate were not. CONCLUSION: A high-Hcy level was a risk factor for atherosclerosis in patients with high Ox-LDL levels. High intakes of antioxidants appeared to be a protective factor for atherosclerosis, perhaps exerting a pro-oxidative effect on LDL when combined with high levels of Hcy and LDL. However, more evidence for the benefits of B vitamins as a homocysteine-lowering therapy is needed.
ABSTRACT
In 2005, the International Diabetes Federation (IDF) presented a new, clinically accessible worldwide definition of 'metabolic syndrome' in a global consensus statement. According to the criteria, central obesity is an essential, not optional, component of metabolic syndrome, which is assessed by ethnicity- and genderspecific cut-off values as measured by waist circumference (WC). Thus we need to have a Korean population-specific WC cut-off values. For this aim, we analyzed data from the 1998 Korean National Health and Nutrition Survey from 6562 participants (2930 men and 3632 women). We determined the appropriate WC cut-offs using receiver operator characteristic (ROC) curve analysis giving the optimal sensitivity and specificity. We estimated multivariate-adjusted odds ratios (ORs) for risk (> or =2metabolic risk factors assessed by IDF) according to the WC categories.The ROC curve analysis indicated that WC was better than BMI in predicting risks. Ageadjusted ORs for having > or =2metabolic risk factors increased abruptly for WC of 90cm in men and 85cm in women, indicating ORs greater than 5.0. WC-compatible 80th percentile was 90cm for men and 86.5cm for women. This analysis demonstrated the appropriate cut-off values of WC for abdominal obesity among Korean are 90cm for men and 85cm for women. These values may be updated, as new data become available.