Antihypertensive Treatment, High Triglycerides, and Low High-Density Lipoprotein Cholesterol and Risk of Ischemic Heart Disease Mortality: A 16-Year Follow-Up in the Copenhagen Male Study

Objective: The aim of this study was to test the hypothesis that metabolic syndrome dyslipidemia is a major risk factor for ischemic heart disease (IHD) mortality among men taking antihypertensive medication. Methods: This was a 16-year follow up of 2,986 men 53-75 years old without overt cardiovascular disease; 357 men used antihypertensive medicine. Potential risk factors were type of baseline medication, blood pressure, diabetes, fasting serum triglycerides (TG), high-density lipoprotein (HDL-C) and total cholesterol, glucosuria, electrocardiogram (ECG) changes, cancer history, body mass index, alcohol and tobacco use, leisure time physical activity, social class, and age. The main outcome was IHD mortality. Results: Men treated for hypertension had a two-fold higher cumulative incidence of IHD mortality during the follow up compared to other men (12.0% vs, 5.8%). Dyslipidemia was defined as TG >= 1.70 mmol/L or HDL-C <= 1.03 mmol/L. Among men without any dyslipidemia (n = 159 or 46%), in Cox analysis adjusted for age only, the hazard ratio (HR) with 95% confidence interval (CI) for IHD mortality was 1.2 (0.6-2.3) compared to untreated normotensives (n = 1,953). Among men with one dyslipidemia (n = 116 or 34%) HR was 2.2 (1.2-4.0), and among men with combined dyslipidemia (n = 71 or 20%) HR was 6.0 (3.5-10.2). Adjustment for relevant confounders attenuated the three HRs to 0.8 (0.4-1.7), 1.6 (0.9-3.1), and 4.5 (2.5-8.2), respectively. Measured blood pressure was not associated with IHD mortality risk among men on antihypertensive medication. Conclusions: TG and HDL-C dyslipidemia were strong effect modifiers. Men on antihypertensive medication had no increased risk of IHD mortality compared to untreated normotensive men, provided they were free from high TG and low HDL-C dyslipidemia.