Abstract Body: Background
Lipoprotein(a) [Lp(a)] is associated with atherosclerotic cardiovascular disease (ASCVD). An Lp(a) threshold of ≥125 nmol/L is commonly used to identify those at higher risk, but there is paucity of data on Hispanic/Latino individuals.

Methods
We evaluated the association between Lp(a) and myocardial infarction (MI), ischemic stroke (IS), and all-cause mortality (ACM) among 16,117 self-identified Hispanic/Latino HCHS/SOL participants. Event rates were compared across Lp(a) quintiles and below/above median IQR. Multivariable Cox proportional hazard models assessed the relationship between events and Lp(a) (log-transformed, per quintiles and above/below 125 nmol/L). Kaplan-Meier curves showed outcome-free survival across quintiles. Sampling weights and survey methods were used to accommodate the stratified probability sampling of the cohort.

Results
Among HCHS/SOL participants (median age 41.1 years, 52.4% female), the median Lp(a) was 19.7 nmol/L (IQR 7.3-60.6), 11.4% had an Lp(a) over 125 nmol/L, and the highest quintile of Lp(a) was >77 nmol/L. Over a median of 9.8 years, 883 events (135 MI, 99 stroke, 649 ACM) occurred. Incident MI and ACM, but not IS, occurred more often in those in the highest quintile of Lp(a) compared with other quintiles. In multivariable models, continuous log-transformed Lp(a) and categorial Lp(a) (fifth quintile) were independently associated with incident MI but not IS or ACM. Lp(a) ≥125 nmol/L was associated with a higher risk of both incident MI and ACM. Outcome-free survival was significantly lower for the highest Lp(a) quintiles, Figure 1.

Conclusion
Hispanic/Latino individuals with elevated Lp(a) are at increased risk of MI and ACM. Although Lp(a) ≥125 nmol/L is a valid risk threshold, Hispanics/Latinos show an increased risk at a lower Lp(a) threshold.