Extracardiac manifestation of elevated lipoprotein(a) levels--cumulative incidence of peripheral arterial disease and stenosis of the carotid artery

Abstract

Elevated lipoprotein(a) (Lp(a)) levels are an accepted risk factor for coronary heart disease. The role of Lp(a) in the development of extracardiac arteriosclerosis like peripheral arterial disease (PAD) and stenosis of the arteria carotis (ACIS) has hardly been documented so far. We aimed to investigate the incidence of extracardiac arteriosclerosis in individuals with elevated Lp(a) values. In our center, we measured Lp(a) levels in 31,734 consecutive patients over 5 years. Of these, 1411 patients were selected retrospectively for the presented analysis. Patients were matched according to age, sex, and other accepted cardiovascular risk factors and were assigned to 6 groups according to their Lp(a) values. Retrospectively, we analysed the incidence of PAD and ACIS. In the group with Lp(a) values <2mg/dl the incidence of PAD was 1.9% (ACIS 2.8%), in the group with Lp(a) 23-29mg/dl 7.3% (6.1%), 30-60mg/dl 9.0% (8.3%), 60-91mg/dl 11.4% (7.9%), 91-110mg/dl 8.6% (6.0%) and >110mg/dl 12.7% (10.9%). None of the patients had LDL levels >130mg/dl or HbA1c 6.1%. Elevated Lp(a) levels seem to be associated with an increased incidence of PAD and ACIS. Even Lp(a) concentrations between 23 and 29mg/dl show a threefold increased risk of PAD when compared to patients with Lp(a) <2mg/dl. However, these findings have to be verified in large prospective studies. In this context cut-off values have to be reevaluated as well.