Coronary Artery Disease-Based Polygenic Risk Score in Early-Onset Acute Myocardial Infarction Subtypes.
BACKGROUND: The coronary artery disease-based polygenic risk score (PRS-CAD) estimates risk of acute myocardial infarction (AMI), but its performance across AMI subtypes in younger individuals, especially women, remains uncertain. OBJECTIVES: The authors assessed PRS-CAD's performance in AMI subtypes. METHODS: We included 2,079 AMI patients aged 18 to 55 years with a 2:1 female-to-male ratio from the VIRGO (Variation in Recovery: Role of Gender on Outcomes of Young Acute Myocardial Infarction Patients) study and 3,761 controls from the MESA (Multi-Ethnic Study of Atherosclerosis) study. AMI subtypes were classified using the VIRGO taxonomy. We evaluated PRS-CAD's association with AMI subtypes using multinomial logistic regression and with 1-year outcomes in AMI subtypes using Cox regression. RESULTS: PRS-CAD was significantly associated with MI due to coronary artery disease (N = 1,876; OR: 1.82 per 1-SD increase; 95% CI: 1.67-1.97; P < 0.001) but not with MI with nonobstructive coronary artery disease (N = 188; OR: 1.13 per 1-SD increase; 95% CI: 0.96-1.34; P = 0.14). PRS-CAD's performance did not differ by sex. A 1-SD increase in PRS-CAD was associated with higher risk of 1-year hospitalization or death in patients with MI with nonobstructive coronary artery disease (HR: 1.50; 95% CI: 1.08-2.10; P = 0.02) but not in patients with MI due to coronary artery disease (HR: 0.98; 95% CI: 0.91-1.07; P = 0.67). CONCLUSIONS: PRS-CAD's association with AMI varied by subtype but not by sex in young adults, warranting caution in application.