Abstract Body: Background: Epidemiological and genetic data suggest that high levels of lipoprotein(a) [Lp(a)] are an independent risk factor for cardiovascular disease (CVD) and are associated with CVD risk even in patients with low LDL cholesterol levels. As a potential therapeutic target, understanding the interaction of Lp(a) with other risk factors in CVD pathogenesis is crucial.

Aim: To identify demographic and clinical variables that enhance the prediction of CVD risk in patients with high Lipoprotein (a) (≥125 nmol/L) [HLp(a)] in a diverse population.

Methods: A descriptive cross-sectional study was conducted in consecutive subjects with Lp(a) measurements in a community-based hospital. Lp(a) levels were measured using an immunoturbidimetry assay. We analyzed the association of HLp(a) with established CVD (history of myocardial infarction, stroke, or arterial vascular disease ≥ 70% stenosis) and used the chi-squared test to determine if the inclusion of additional clinical variables improved CVD prediction.

Results: Among 873 patients included, 22% (192 of 873) had HLp(a) with the highest prevalence observed in African Americans (AA) compared to other ethnic groups [50% (110 of 220) vs 15.4% (101 of 653), p < 0.001]. The HLp(a) group had a mean age of 64 ± 13 years, 48% (92 of 192) were female, and 43% (83 of 192) were AA. By univariate analysis, the prevalence of CVD was significantly higher in patients with a history of hyperlipidemia [97% (134 of 138) vs 87% (47 of 54), p < 0.007), hypertension [79% (109 of 138) vs 64% (35 of 54), p = 0.04], HDL ≤ 40 mg/dl [20% (28 of 138) vs 7% (4 of 54), p = 0.03], and coronary artery calcium (CAC) score > 50^th percentile [87% (39 of 45) vs 36% (9 of 25), p < 0.001]. The predictive value of CVD for patients with HLp(a) alone was 71.9% (138 of 192) and increased to 81.2% (39 of 48) and 87.5% (28 of 32) with inclusion of low HDL and CAC score > 50^th percentile respectively. When both HDL ≤ 40 mg/dl and CAC score > 50^th percentile were included, the predictive value of CVD was 100% (8 of 8).

Conclusion: CAC score > 50^th percentile and HDL ≤ 40 mg/dl enhance the identification of CVD in patients with high Lp(a) levels. These findings suggest that incorporating CAC score and HDL measurements may enhance risk stratification for patients with high Lp(a), informing personalized treatment strategies.