Very low lipoprotein(a) and increased mortality risk after myocardial infarction

Abstract

Background: Inconclusive data exist on risk associated with Lp(a) in patients after myocardial infarction (MI). Aims of the present study were to evaluate the association of Lp(a) level with total mortality and recurrent cardiovascular events.

Design and methods: Single center prospective registry of consecutive patients hospitalized for acute myocardial infarction between June 2017 and June 2020 at a large tertiary cardiac center with available blood samples drawn <24h of admission.

Results: Data from 851 consecutive patients hospitalized for MI were evaluated. During the median follow-up of 19 months (interquartile range 10-27), 58 (6.8%) patients died. Nonlinear modelling revealed a U-shaped association between Lp(a) and total mortality risk. Compared to patients with Lp(a) ranging between 10-30 nmol/L and after multivariate adjustment, total mortality risk was increased both in patients with Lp(a)<7 nmol/L (hazard ratio (HR) 4.08, 95% confidence interval (CI) 1.72-9.68) and Lp(a) ≥125 nmol/L (HR 2.92, 95% CI 1.16-7.37), respectively. Similarly, the risk of combined endpoint of acute coronary syndrome recurrence or cardiovascular mortality was increased both in patients with low (sub-HR 2.60, 95% CI 1.33-5.08) and high (sub-HR 2.10, 95% CI 1.00-4.39) Lp(a). Adjustment for heart failure signs at the time of hospitalization weakened the association with total mortality and recurrent cardiovascular events.

Conclusions: In the present analysis, both high and low concentrations of Lp(a) were associated with an increased risk of total mortality and recurrent cardiovascular events after MI. The excess of mortality associated with Lp(a) was partially attributable to more prevalent heart failure.

Keywords: Cholesterol; Lipoprotein(a); Myocardial infarction; Secondary prevention.