THE ROLE OF INSULIN-RESISTANCE IN KOREAN PATIENTS WITH CORONARY ATHEROSCLEROSIS

To determine whether dietary modification improves insulin resistance and coronary atherosclerosis, we randomly assigned 14 Korean patients to an experimental group (low-fat, low-cholesterol diet, high polyunsa turated/saturated fatty acid ratio, and calorie restriction) or to a c ontrol group (no dietary change). Coronary artery lesions were analyze d by quantitative coronary angiography, and postglucose insulin respon ses were measured. At baseline, there were no significant differences in body weight, BMI, waist-to-hip ratio (WHR), and plasma lipid and in sulin levels between the two groups. After completion of the 1-year di et program, the experimental group showed significant reductions in bo dy weight (66.0 +/- 3.2 to 61.6 +/- 3.8 kg [means +/- SE], P < 0.01) a nd WHR (0.96 +/- 0.01 to 0.93 +/- 0.01, P < 0.05). Total cholesterol ( 5.45 +/- 0.45 to 4.50 +/- 0.44 mmol/l, P < 0.05), LDL cholesterol (3.7 1 +/- 0.36 to 2.98 +/- 0.37 mmol/l, P < 0.05), and triglyceride (1.91 +/- 0.28 to 1.29 +/- 0.17 mmol/l, P < 0.05) were also significantly re duced in the experimental group. The mean insulin response during an o ral glucose tolerance test was also significantly decreased (258.6 +/- 26.4 to 181.8 +/- 6.6 pmol/l, P < 0.05). in contrast, there mere no s ignificant changes in these parameters in the control group. When only coronary artery lesions >50% stenosed were analyzed, the average perc entage diameter stenosis regressed from 63.2 to 56.8% in the experimen tal group, However, there were no significant changes in the control g roup. Our trial suggests that decreases in body weight and WHR and an improvement in insulin resistance with a low-fat, low-cholesterol diet and caloric restriction may reduce risk factors and reverse coronary atherosclerotic lesions in 1 year.