Lipoprotein(a) as a Determinant of Coronary Heart Disease in Young Women

Abstract

Background Lipoprotein(a) [Lp(a)] appears to be a risk factor for coronary heart disease (CHD) in men. The role of Lp(a) in women, however, is less clear. Methods and Results We examined the ability of Lp(a) to predict CHD in a population-based case-control study of women 65 years of age or younger who lived in the greater Stockholm area. Subjects were all patients hospitalized for an acute CHD event between February 1991 and February 1994. Control subjects were randomly selected from the city census and were matched to patients by age and catchment area. Lp(a) was measured 3 months after hospitalization by use of an immunoturbidometric method (Incstar) calibrated to the Northwest Lipid Research Laboratories (coefficient of variation was <9%). Of the 292 consecutive patients, 110 (37%) were hospitalized for an acute myocardial infarction, and 182 were hospitalized (63%) for angina pectoris. The mean age for both patients and control subjects was 56±7 years. Of participants, 74 patients (25%) and 84 control subjects (29%) were premenopausal. The distributions of Lp(a) were highly skewed in both patients and control subjects, with a range from 0.001 to 1.14 g/L. Age-adjusted odds ratio for CHD in the highest versus the lowest quartile of Lp(a) was 2.3 (95% confidence interval [CI], 1.4 to 3.7). After adjustment for age, smoking, education, body mass index, systolic blood pressure, total cholesterol, triglycerides, and HDL, the odds ratio was 2.9 (95% CI, 1.6 to 5.0). The odds ratios were similar when myocardial infarction and angina patients were compared with their respective control subjects. The odds ratios were 5.1 (95% CI, 1.4 to 18.4) and 2.4 (95% CI, 1.3 to 4.5) in premenopausal and postmenopausal women, respectively. Conclusions These results suggest that Lp(a) is a determinant of CHD in both premenopausal and postmenopausal women.