The roles of apo E genotype, gender and adipokines in blood plasma lipids in Caucasians with well-controlled type 2 diabetes

Abstract

Cape Breton Island has among the highest levels of type 2 diabetes in Canada and therefore the risk of associated coronary atherosclerosis-induced myocardial infarction is also very high. Fasting blood serum lipid concentrations are important measures of coronary atherosclerosis disease risk in type 2 diabetics. Apolipoprotein E alleles and genotypes, as well as the adipocytokines, leptin and adiponectin modify fasting blood serum lipid levels and thus the degree of atherosclerosis which may be assessed in part by c-reactive protein (CRP). Control of blood lipid levels is critical to reducing the risk of myocardial infarction. It was hypothesised that there would be no gender differences in myocardial infarction risk including CRP levels and at least some of the lipid levels including their modulating levels of apolipoprotein alleles and genotypes, leptin and adiponectin. The purpose of this study was to assess this hypothesis. Females had significantly higher levels of high density lipoprotein cholesterol (HDL-c) and its atherogenic subfraction HDL2-c while at the same time having higher levels of HDL3-c. Serum free fatty acids levels were significantly higher in females as was the leptin level. There were no gender differences in elevated total cholesterol (TC), low density lipoprotein-cholesterol (LDL-c), small dense (sd) LDL-c, triglycerides, lipoprotein(a), adiponectin and CRP and the ratios of HDL-c: TC and HDL-c: LDL-c. By trend or significantly, Apo E genotypes and allele presence correlated variously by gender with some lipid levels. Thus despite the higher degree of antiatherogenic HDL-c and HDL2-c in females, this was not manifested in lesser atherosclerotic severity as assessed by CRP. This may be due to the fact that HDL-c and HDL2-c were low as was ratio of HDL-c: TC and HDL-c: LDL-c. Thus it is concluded that apo E genotype, lipid levels and the ratios of HDL-c: TC and HDL-c: LDL-c equally favour atherosclerosis in both males and female type 2 diabetics in Cape Breton and more aggressive intervention is required to ameliorate the substantial risk of atherosclerosis induced myocardial infarction presented by these lipid profiles. However, this was only a small study and a larger study would more definitively address the risk of myocardial infarction in both males and females on Cape Breton.