Lipoprotein(a) Testing for Cardiovascular Risk Assessment and Use of Lipid-Lowering Therapy in a Large Midwest Cohort

The atherogenic lipoprotein(a) [Lp(a)] is recommended to be measured at least once in each adult person's lifetime. However, the testing frequency and its impact on lipid-lowering therapy is uncertain.

This retrospective analysis included patients 40-79 years old with at least two ambulatory clinic visits to a Midwestern healthcare system between 2018-2022. Within those patients, Lp(a) testing dates to 2004. Parameters included age, sex, race, traditional ASCVD risk factors, Lp(a) levels, and lipid-lowering therapy (LLT) prevalence. Lp(a) was considered elevated if Lp(a) ≥50 mg/dL or ≥125 nmol/L, respectively.

Patients (n = 419,812) in the sample had a median (IQ range) age of 61 (52 - 71) years, with 61 % with dyslipidemia and 11 % ASCVD. Over 18 years, only 1.4 % of those without prior ASCVD and 4.9 % of those with ASCVD were tested for Lp(a). Median (IQR) Lp(a) levels in patients with and without ASCVD in mass and particle number were 20 (8, 55) mg/dL and 47 (19, 129) nmol/L, and 27 (10, 76) mg/dL and 59 (20, 174) nmol/L, respectively. Compared to those with normal Lp(a) levels, the prevalence of LLT was higher in patients with elevated Lp(a) across ASCVD risk categories including low risk patients (59 % vs 47 %) and those with established ASCVD (88 % vs 85 %).

Although testing for Lp(a) has improved, there is room for significant improvement, particularly in those with ASCVD. The higher use of LLT in all risk categories indicate that Lp(a) testing may have influenced treatment decisions.