Sex-Related Differences in Outcomes for Patients With ST Elevation Myocardial Infarction (STEMI): A Tamil Nadu-STEMI Program Subgroup Analysis

Background ST elevation myocardial infarction (STEMI) represents a large proportion of the clinical presentation of coronary artery disease in Indian people. Owing to multiple factors contributing to the sex difference, women with STEMI are thought to have a higher risk of adverse outcomes than men. The aim of this study was to evaluate sex-related differences in the clinical characteristics and prognosis of patients with STEMI within a system of care. Method This study was a subgroup analysis of the Tamil Nadu-STEMI (TN-STEMI) program, a multicentre, prospective, observational study of a quality-improvement program studying patients with STEMI at four hub-and-spoke clusters in the southern state of Tamil Nadu, India. In total, 2,420 patients were enrolled between 2012 and 2014, and the data from all four clusters, pre- and postimplementation of integrated STEMI systems, were combined for this analysis, with a 1-year follow-up. Results The mean +/- SD age of presentation of female patients (16%) was significantly later (60.1 +/- 10.9 years) compared with males (84%; 53.7 +/- 12 years). Diabetes was more prevalent in women (35.2% vs 23.8%; p<0.001), as was hypertension (35.2% vs 22.9%; p<0.001). Symptom to first medical contact in female patients was significantly delayed compared with males (193 mins vs 170 mins; p <= 0.009). Women had higher mortality, both in hospital (10.4% vs 4.8%; p <= 0.001) and at 1 year (26.7% vs 13%; p <= 0.001). This pattern was persistent, even in the younger STEMI (<45 years) population (in-hospital: 9.1% vs 3% [p <= 0.05]; at 1 year: 18.2% vs 3% [p <= 0.05]). In the regression model, females had a 1.8 times increased likelihood (p<0.04) of mortality after adjusting for confounders. Conclusions Among patients with STEMI, women have an unfavourable risk profile and adverse short- and long-term prognoses when compared to men.