Prevalence and Predictors of Lipoprotein(a) Measurement in Younger Patients Following ST-Elevation Myocardial Infarction.

BACKGROUND: Lipoprotein(a) [Lp(a)] level is a well established, independent risk factor for premature atherosclerotic cardiovascular disease. The 2021 Canadian Cardiovascular Society dyslipidemia recommendations advise that Lp(a) measurement be performed as part of cardiovascular risk stratification. However, little is known about the clinical adoption of this recommendation, particularly as undertaken for young patients presenting with acute coronary syndromes. METHODS: This study assessed the prevalence and predictors of Lp(a) measurement in a contemporary cohort of patients aged ≤ 65 years presenting with ST-elevation myocardial infarction (STEMI) in Vancouver, Canada between January 2016 and January 2023. The primary outcome was the proportion of such patients who had a measurement of Lp(a) prior to or within 1 year of index STEMI hospitalization. Secondary analyses explored predictors of Lp(a) measurement at any point in the lifetime, as well as measurement trends through years. RESULTS: A total of 1106 patients were studied (mean age 55.9 years; 88.1% male). Only 240 patients (21.7%) had Lp(a) level assessed within 1 year of STEMI. The rate of Lp(a) measurement increased from 15% to 39% during the interval from 2016-2023 (P < 0.01 for trend). Older age (OR 0.67; 95% confidence interval [CI] [0.60, 0.75], P < 0.01), prior history of smoking (OR 0.65; 95% CI [0.46, 0.91], P = 0.01), and earlier year of STEMI in the study period (OR 0.83; 95% CI [0.77, 0.90], P < 0.01) were independently associated with a lower likelihood of Lp(a) measurement. CONCLUSIONS: Although rates of measurement have increased from 2016 to 2023, Lp(a) testing remains underutilized among younger STEMI patients. Strategies are needed to increase the testing of Lp(a) level among younger patients with STEMI, especially with the development of novel targeted therapeutics.