Sex difference in the risk factor distributions and outcomes after coronary artery bypass graft surgery in the young population.

OBJECTIVES Coronary artery disease is becoming a major health concern in the young population. Male and female patients may experience different journeys after coronary artery disease events. We aimed to evaluate risk factors and compare outcomes between young male and female patients undergoing coronary artery bypass graft surgery (CABG). METHODS In this registry-based large sample size study, patients undergoing isolated CABG at a young age (premature isolated CABG) between 2007 and 2016 were included and followed up until 2020. Premature was defined as women and men younger than 55 years old. The main end points of the study were 7-year all-cause mortality and 7-year major adverse cardiovascular and cerebrovascular events (MACCEs). RESULTS Of a total of 24 428 patients who underwent CABG, 7217 patients (men-to-women ratio ≈4:1) with premature isolated CABG were included. The median follow-up duration was 78.5 months (75.2-81.6 months). The prevalence rates of diabetes mellitus, hypertension, dyslipidaemia and obesity were significantly higher in women than in men (58.3% vs 28.6%, 64.2% vs 38.5%, 69.7% vs 55.3% and 44.7 vs 23.9, respectively; all Ps < 0.05). The risk factor burden (mean of the risk factor count per year) was also higher among the female population. Diabetes mellitus was the common mortality predictor between men and women. In the subgroup analysis (interaction analysis in the adjusted model), hypertensive females had a higher rate of MACCE and a higher rate of mortality than hypertensive males; however, this difference was not significant in the non-hypertensive population. Opium addiction was a strong predictor of MACCE and all-cause mortality among men. Female patients had a higher rate of 7-year MACCE (hazard ratio, 1.33; 95% confidence interval, 1.16-1.51) and a higher rate of 7-year all-cause mortality (hazard ratio, 1.23; 95% confidence interval, 0.98-1.53). CONCLUSIONS The risk factor profile and predictors of outcomes were different between our female and male patients. Women carried a higher risk of events and mortality after CABG at a young age.