Lipoprotein (a) and development of intermittent claudication and major cardiovascular events in men and women: the Edinburgh Artery Study.

ABSTRACT

Lipoprotein (a) may be an important risk factor for atherosclerosis. It is widely accepted that lipoprotein (a) levels are raised in patients with coronary heart disease, but there is some doubt about the causality of the relationship. In addition, little is known about the relationship between lipoprotein (a) and either stroke or peripheral arterial disease, nor about the role of lipoprotein (a) in women. Subjects aged 55-74 years (n=1592) were selected at random from 11 general practices in Edinburgh, Scotland and followed up for 5 years. The incidences of myocardial infarction, intermittent claudication and stroke were 13.4, 9.4 and 3.7%, respectively. Raised lipoprotein (a) levels at baseline were associated with an increased risk (95% confidence interval) of myocardial infarction RR 1.15 (1.00, 1.32), intermittent claudication RR 1.32 (1.10, 1.57) but not significantly for stroke RR 1.24 (0.93, 1.64). This increased risk persisted for intermittent claudication after adjustment for baseline cardiovascular disease and other risk factors RR 1.20 (1.00, 1.43), but for myocardial infarction became non-significant RR 1.06 (0.91, 1.23). The risk of disease associated with raised lipoprotein (a) was slightly higher in women than in men, especially for intermittent claudication (men RR 1.09 (0.87, 1.36) compared to women RR 1.37 (1.01, 1.87)). In conclusion, we found that lipoprotein (a) was an independent predictor of cardiovascular events in both sexes. The association between lipoprotein (a) and cardiovascular events may have been stronger in women than in men, and for peripheral arterial disease than myocardial infarction and stroke.