Association of coronary artery ectasia with plasma insulin levels in Japanese men of heterozygous familial hypercholesterolemia with the low-density lipoprotein receptor gene mutation K790X

Background: Hyperinsulinemia is widely believed to be an important coronary risk factor. We investigated the effect of plasma insulin levels on the development of coronary ectasia in Japanese men with heterozygous familial hypercholesterolemia (FH). Methods: A cross-sectional study was conducted in 20 FH men with the LDL receptor mutation (K790X) [age 42.3 +/- 2.8 years old, body mass index (BMI) 24.6 +/- 0.7 kg/m(2), total cholesterol (TC) 8.68 +/- 0.36 mmol/l, triglycerides (TG) 1.76 +/- 0.23 mmol/l, high-density lipoprotein cholesterol (RDL-C) 0.977 +/- 0.065 mmol/l]. Subjects with diabetes mellitus were excluded. Plasma insulin levels, either fasting or during oral glucose tolerance test, were compared between subjects with and without coronary artery ectasia. Results: FH subjects with coronary ectasia had significantly higher fasting plasma insulin levels than those without (12.6 +/- 1.4 vs. 7.7 +/- 0.5 mU/l;p < 0.05). Also, plasma insulin levels during oral glucose tolerance test tended to be higher in the former than in the latter. Conclusions: Plasma insulin level could be an important determinant of the development of coronary artery ectasia in Japanese heterozygous FH men. (c) 2004 Elsevier B.V. All rights reserved.