Abstract P282: Pooled Cohort Equation Performance at Quantile Thresholds of African and European Ancestry Among Hispanic/Latino: Findings From Multi-Ethnic Study of Atherosclerosis (MESA)

Background: Current recommendations include using the non-Hispanic White (NHW) pooled cohort equation (PCE) for 10-year atherosclerotic cardiovascular disease (ASCVD) risk estimation among Hispanic individuals and the non-Hispanic Black (NHB) PCE when African ancestry is present. We studied PCE performance at thresholds of African and European ancestry among US Hispanics. Methods: Hispanic participants from the Multi-Ethnic Study of Atherosclerosis (MESA), ages 44-75 years without diabetes mellitus or prior cardiovascular disease were included. ADMIXTURE software was used to estimate quantile thresholds of continental genetic ancestry (African and European). We compared 10-year survival Kaplan-Meier estimates among Mexican Hispanics, Caribbean Hispanics and Other Hispanics using a log-rank analysis. We calculated the predicted-to-observed (P/O) ASCVD event ratios using the NHW and NHB PCE across quantile threshold of African and European ancestry. Results: 966 MESA Hispanics were stratified into: Mexican (n=504), Caribbean (n=284) or Other Hispanic (n=178). At 10-years, there were 179 ASCVD events [Mexicans (n=107), Caribbean (n=49), Other Hispanic (n=23)]. We observed overestimation using the NHW and NHB PCE as evidenced by P/O ratios >1. Both PCEs performed better (P/O ratios converge toward 1) with increasing quantiles of European Ancestry and performed worse (P/O ratios diverge from 1) with increasing quantiles of African Ancestry. At a greater than 0.7 quantile of African ancestry, a sharp increase in overestimation was recorded for both PCEs. (Fig1A). Though Mexican Hispanics had the lowest ASCVD-free survival probability at 10 years’ time mark, results were not statistically significant. (Fig 1B) Conclusion: We observed overestimation in the 10-year ASCVD risk estimation using the NHW and NHB PCE among Hispanics as evidenced by P/O ratios >1. Both PCEs performed better with increasing quantiles of European ancestry and performed poorly with increasing quantiles of African ancestry.