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/aims: Racial differences in lipid and cardiovascular risk profiles are well-established, including for Asians. We compared cardiovascular treatment effects of ω-3 carboxylic acid (CA) between Asians and non-Asians in this post-hoc analysis of the STRENGTH trial.

Methods: The STRENGTH trial was a double-blinded randomized controlled trial of 13,078 high cardiovascular risk patients enrolled at 675 global centers. Efficacy and interactions of ω-3 CA for Asians (n = 1355) and non-Asians (n = 11,723) were assessed. The primary endpoint is a 5-point composite of cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, coronary revascularization, and unstable angina hospitalizations.

Results: In Asians, ω-3 CA was associated with significantly reduction in the primary endpoint during 3.6 ± 0.7 years follow-up with 81/698 (Kaplan-Meier estimate (KME): 14.8 %) events in the ω-3 CA group, 103/657 (KME: 20.4 %) events in the corn oil group, hazard ratio (HR) 0.72, 95 %CI 0.54-0.96, p = 0.03. In non-Asians, there was not a significant difference in primary endpoint rates, 704/5841 (KME: 15.6 %) events in the ω-3 CA group, 692/5882 (KME: 15.9 %) events in the corn oil group, HR 1.03 95 %CI 0.93-1.14, p = 0.60. There were significant interactions between race (Asian vs non-Asian) and treatment group for the primary endpoint (p = 0.02) and non-fatal stroke (p = 0.02).

Conclusion: In this exploratory analysis from the neutral STRENGTH trial, ω-3 CA was associated with significant reduction in the primary endpoint in Asians but not in non-Asian patients with high cardiovascular risk. Further, ideally randomized, research is necessary to assess these hypothesis-generating findings and elucidate potential mechanisms for beneficial effects of ω-3 CA in Asians.