Lipoprotein (a) levels and outcomes in stable outpatients with symptomatic artery disease

Abstract

Background and aims: Although genetic and epidemiological studies support that people with high lipoprotein (a) [Lp(a)] levels are at an increased risk for arterial disease, its prognostic value in patients with established artery disease has not been consistently evaluated.

Methods: FRENA is a prospective registry of consecutive outpatients with coronary, cerebrovascular or peripheral artery disease. We assessed the risk for subsequent myocardial infarction, ischemic stroke or limb amputation according to Lp(a) levels at baseline.

Results: As of December 2016, 1503 stable outpatients were recruited. Of these, 814 (54%) had levels <30 mg/dL, 319 (21%) had 30-50 mg/dL and 370 (25%) had ≥50 mg/dL. Over a mean follow-up of 36 months, 294 patients developed subsequent events (myocardial infarction 122, ischemic stroke 114, limb amputation 58) and 85 died. On multivariable analysis, patients with Lp(a) levels of 30-50 mg/dL were at a higher risk for myocardial infarction (hazard ratio [HR]: 4.67; 95%CI: 2.77-7.85), ischemic stroke (HR: 8.27; 95%CI: 4.14-16.5) or limb amputation (HR: 3.18; 95%CI: 1.36-7.44) than those with normal levels. Moreover, patients with levels ≥50 mg/dL were at increased risk for myocardial infarction (HR: 19.5; 95%CI: 10.5-36.1), ischemic stroke (HR: 54.5; 95%CI: 25.4-116.7) or limb amputation (HR: 22.7; 95%CI: 9.38-54.9).

Conclusions: Stable outpatients with symptomatic artery disease and Lp(a) levels >30 mg/dL were at a 5-fold higher risk for subsequent myocardial infarction, stroke or limb amputation. Those with levels >50 mg/dL were at an over 10-fold higher risk.

Keywords: Lipoprotein (a); Recurrent cardiovascular outcomes; Secondary prevention.