Clinical characteristics and cardiovascular outcomes among young patients with acute myocardial infarction in Kerala, India: A secondary analysis of ACS QUIK trial

Background: Limited data exist on the risk profile and outcomes among young patients with acute myocardial infarction(AMI) in low-and middle-income countries(LMICs). This study explored differences in the clinical characteristics, medical care, and outcomes of AMI in young adults in India with a subanalysis focusing on sex disparities amongst the young.

Methods: Using the Acute Coronary Syndrome Quality Improvement in Kerala trial database, we compared baseline characteristics, management, and outcomes amongst the young patients(≤50 years) and their older counterparts. The primary outcomes were the rates of in-hospital and 30-day composite of in-hospital major adverse cardiovascular events(MACE).

Results: Of the 21,374 adults enrolled, 4762(22%) were young, of which 614 (12.9%) were females. Young patients with AMI were more likely to be smokers(41.9% vs. 27.8%;P < 0.001) and undergo coronary angiography (66.3%vs.57.3%;P < 0.001) and percutaneous coronary intervention (PCI)(57.5% vs. 47.0%;P < 0.001), compared to older patients. After adjustment for potential confounders, younger patients had a lower likelihood of in-hospital (RR = 0.49; 95%CI 0.40-0.61;P < 0.001) and 30-day MACE (RR = 0.54; 95%CI 0.46-0.64;P < 0.001). Subgroup analysis comparing young males and females revealed worse cardiovascular risk profile among young women except for smoking. In-hospital MACE(RR = 1.60; 95%CI, 1.0-2.45;P = 0.048) were higher for young women compared to men.

Conclusion: Young AMI patients had higher prevalence of modifiable risk factors, were more likely to receive reperfusion therapy, and had better short and intermediate outcomes, compared to older patients. Compared to young men with AMI, young women had worse cardiovascular risk profile, were less likely to be treated with diagnostic angiography or PCI and experienced higher in-hospital death and MACE.