Gender-related differences among patients with STEMI: A propensity score analysis

Abstract

Introduction and objectives: Female sex is believed to be a significant risk factor for mortality among patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary interventions (pPCI). Methods: We collected data on all consecutive STEMI patients treated with pPCI within 12 hours and compared the males vs the females. The primary endpoint was long-term mortality one month after hospital discharge. The secondary endpoint was 30-days mortality. Results: From March 2006 to December 2016, 1981 patients underwent pPCI at our hospital, 484 (24.4%) were females. Compared with men, women were older (mean age 71.3 ± 11.6 vs 62.9 ± 11.8 years, P < .001), less smokers (26.7% vs 72.7%; P < .001), more diabetic (28.0% vs 22.3%; P < .002), more hypertensive (69.6% vs 61.3%; P < .001), presented more often with shock at baseline (13.2% vs 9.0%; P = .006), had longer symptoms-to-balloon time frames (5.36 ± 3.97 vs 4.47 ± 3.67 hours; P < .001). Also, women were less likely to receive glycoprotein IIb-IIIa inhibitors (59.5% vs 71.4%; P < .001) and stents (79.5% vs 86.6%; P = .01). During the 30-day and long-term follow-up (mean 4.9 ± 3.2 years) the female sex was associated with a higher mortality rate (8.9% vs 4.0%, P < .001 and 23.8% vs 18.4%, P = .01, respectively). After propensity score matching, 379 men and 379 women were selected. Female sex continued to be associated with a higher death rate at 30 days (9.5% vs 5.5%; P = .039) but not in the long term among survivors (25.6% vs 21.4%; P = .170). Conclusions: Compared to men, women with STEMI undergoing pPCI had higher 30-day mortality rates. However, among survivors, the long-term mortality rate was similar. Even if residual confounding cannot be ruled out, this difference in the outcomes may be partially explained by biological sex-related differences.