Alteration of lipoprotein(a) concentration with glycemic control in non-insulin-dependent diabetic subjects without diabetic complications

Abstract

Recently, a high plasma level of lipoprotein(a) [Lp(a)] has been considered an independent risk factor for atherosclerosis and its sequelae, particularly myocardial infarction. Patients with non-insulin-dependent diabetes mellitus (NIDDM) have an increased mortality rate from cardiovascular and cerebrovascular disease. Therefore, plasma concentrations of Lp(a) were determined and the relationship between fasting plasma Lp(a) level and diabetic control was investigated in NIDDM patients without any diabetic complications. Fasting plasma Lp(a) levels were measured using enzyme-linked immunosorbent assay kits [Terumo Medical Corp, Elkton, MD, Lp(a)] in 61 NIDDM subjects (30 men aged 56 ± 2.0 years, 31 women aged 53 ± 2.1 years [mean ± SEM]) who were without any diabetic macroangiopathy and microangiopathy such as retinopathy, nephropathy, and neuropathy and in 56 healthy age- and sex-matched controls. Plasma Lp(a) levels were significantly higher in the diabetic group than in the control group (23.5 ± 2.5 v 11.7 ± 1.4 mg/dL [mean ± SEM], P < .001). There was no significant correlation between log-transformed plasma Lp(a) levels and other factors such as age, sex, body mass index (BMI), blood pressure, duration of diabetes, fasting plasma glucose (FPG) level, glycosylated hemoglobin (HbA 1C) level, and plasma lipid levels except for low-density lipoprotein cholesterol (LDL-C) levels in diabetic patients. A significant positive correlation was noted in diabetic patients between the changes of log Lp(a) and HbA 1C levels after a 3-month follow-up period ( P < .05). Our data indicate that NIDDM patients without any diabetic complications have high concentrations of plasma Lp(a) compared with healthy control subjects, and that improved glycemic control may reduced plasma levels of Lp(a).