Abstract 4120785: Differential Cardiovascular Impact of ω-3 Fatty Acid in Patients at High Cardiovascular Risk in Asians versus non-Asians: Sub-analysis of the STRENGTH Randomized Clinical Trial

Background: Racial differences in lipid and cardiovascular risk profiles are well-established including for Asians. The STRENGTH trial found that ω-3 carboxylic acid (CA) formulation of eicosapentaenoic acid and docosahexaenoic acid did not result in significant changes in cardiovascular event rates compared with corn oil in statin-treated patients at high cardiovascular risk, however drug efficacy may vary by race. We evaluated and compared the cardiovascular treatment effect of ω-3 CA between Asians and non-Asians in this sub-analysis of the STRENGTH trial. Methods: The STRENGTH trial was a double-blinded 1:1 randomized controlled trial of 13,078 high cardiovascular risk patients enrolled during 10/30/2014-6/14/2017 at 675 centers. Efficacy of ω-3 CA for Asians (n=1,355) and non-Asians (n=11,723) and interactions between race and treatment effect were assessed. The primary endpoint is a composite of cardiovascular death, non-fatal myocardial infarction, stroke, coronary revascularization and unstable angina hospitalizations. Results: Key differences in baseline characteristics include Asians having significantly higher prevalence of men, secondary prevention, and lower total cholesterol, LDL, apoB100, and hsCRP. In Asians, ω-3 CA was associated with significantly lower primary endpoint during follow-up, with 81/698 events [Kaplan-Meier (KM) Estimate: 14.8%] in the ω-3 CA group, 103/657 events (KM Estimate: 20.4%) in the corn oil group, and hazard ratio (HR) 0.72, 95% CI 0.54-0.96, P=0.026 (Figure A). In non-Asians, there was not a significant difference in primary endpoint rates between the two groups, with 704/5841 events (KM Estimate: 15.6%) in the ω-3 CA group, 692/5882 events (KM Estimate: 15.9%) in the corn oil group, and HR 1.03 95% CI 0.93-1.14, P=0.60 (Figure B). There were significant interactions between race (Asian versus non-Asian) and treatment group for the primary endpoint (P=0.021) and non-fatal stroke (P=0.016) and remained significant after adjusting for other covariates. Conclusion: ω-3 CA was associated with significant reduction in major adverse cardiovascular events compared with corn oil in Asians but not in non-Asian patients with high cardiovascular risk. Further research is necessary to elucidate the mechanisms for potentially beneficial effects of ω-3 CA unique to Asian race.