Atherosclerosis. 2013 Jun;228(2):491-5.
Association of arterial stiffness and diabetes with triglycerides-to-HDL cholesterol ratio for Japanese men: the Nagasaki Islands Study.
Shimizu Y, Nakazato M, Sekita T, Kadota K, Yamasaki H, Takamura N, Aoyagi K, Maeda T.
Department of Community Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan. email@example.com
Although many studies have reported that elevated serum triglycerides to high-density lipoprotein cholesterol (TG-HDL) ratios constitute a risk for insulin resistance and increased arterial stiffness, no study has clarified as yet the association, in terms of the TG-HDL ratio, between diabetes and increased arterial stiffness evaluated by means of carotid intima-media thickness (CIMT) and cardio-ankle vascular index (CAVI). To investigate this association, we conducted a cross-sectional study of 1344 Japanese men aged 36-79 years undergoing a general health check.
We investigated the associations between atherosclerosis/arterial stiffness, evaluated by means of CIMT and CAVI, and diabetes for all subjects, who were divided into tertiles according to TG-HDL levels. Diabetes was defined as HbA1c (NGSP) ≥6.5%, and/or initiation of glucose-lowering medication or insulin therapy.
Of the 130 diabetes patients identified in the cohort, 56 patients had high TG-HDL (high TG-HDL diabetes) and 43 had low TG-HDL (low TG-HDL diabetes). We found that only diabetic patients with high TG-HDL were at a significant risk for atherosclerosis (diagnosed as CIMT ≥ 1.1 mm) and increased arterial stiffness (diagnosed as CAVI ≥ 8.0). The multivariable-adjusted odds ratios and 95% confidence intervals of atherosclerosis and increased arterial stiffness for diabetes were 2.67 (95%CI: 1.35-5.28) and 2.36 (95%CI: 1.01-5.50), for total TG-HDL diabetes 2.57 (95%CI: 1.32-5.02) and 3.56 (95%CI: 1.50-8.46) for high TG-HDL diabetes, and 1.17 (95%CI: 0.52-2.63) and 0.80 (95%CI: 0.33-1.90) for low TG-HDL diabetes, respectively.
Diabetes, especially high TG-HDL diabetes, constitutes a significant risk for increased arterial stiffness and atherosclerosis.
We also reported that hemoglobin levels were positively associated with arterial stiffness (CAVI≥9) for non-anemic non-overweight (BMI<25kg/m2) Japanese men (1) and in another sex-combined study of ours we found a positive association of hemoglobin levels with high TG-HDL diabetes and an inverse association with low TG-HDL diabetes (2). These findings suggest that diabetes categorized by TG-HDL levels may serve as an effective tool for estimating risk of atherosclerosis for diabetes patients.
Asian type 2 diabetes patients are reportedly characterized by lower body mass index (BMI) and lower serum insulin levels than their non-Asian counterparts. We also detected a significant inverse association of BMI with low-TG-HDL diabetes and a significant positive association with high TG-HDL diabetes (3). These results indicate that the risk of atherosclerosis for Asian diabetes patients is lower than that for their non-Asian counterparts.
However, the cut-off points for categorizing diabetes in terms of TG-HDL ratios has not yet been clarified. Further studies with different racial populations and direct insulin resistance data are therefore needed.
Furthermore, because our studies are cross-sectional study, we could not establish any causal relationships, so that longitudinal studies are also necessary.
- Shimiuz Y, et al. Association between hemoglobin levels and arterial stiffness for general Japanese population in relation to BMI status: The Nagasaki Islands Study. Geriatr Gerontol Int. 2013 in press.
- Shimizu Y, et al. Association between the hemoglobin levels and hypertension in relation to the BMI status in a rural Japanese population: The Nagasaki Islands study. Intern Med. 2013 in press.
- Shimizu Y, et al. Body mass index triglyceride-to-HDL-cholesterol ratio in relation to risk of diabetes: The Nagasaki Islands study. Acta Med Nagasaki. 2013 in press