Sex-related Differences in Exercise Capacity Trends and Determinants after Cardiac Rehabilitation in Patients with Acute Myocardial Infarction.

Abstract

This study aimed to investigate whether longitudinal changes in exercise capacity in patients with acute myocardial infarction (AMI) differ by sex and clarified what contributed to these differences. We retrospectively examined the differences in each variable between men and women in 156 patients with AMI (mean age: 65 ± 12 years; 82.0% male) who participated in a 3-month cardiac rehabilitation (CR) program and could be followed-up for exercise capacity 12-months after AMI onset. Sex-related differences in the change in peak oxygen uptake (peak VO2) at baseline, 3-months, and 12-months after AMI were analyzed. Male patients with AMI were younger and had higher body mass index and employment rate than women. The attendance of the CR program was higher in women (men vs. women; 10 [3-15] vs. 14 [11-24] sessions, p = 0.0002). Women showed a significant lower %change in peak VO2 after 12 months (men vs. women; 7.8% [-0.49% to 14.6%] vs. 1.3% [-5.7% to 7.5%], p = 0.013). In multiple linear regression analysis, age (β = -0.76, 95% confidence interval [CI] = -1.0 to -0.50, p <0.0001) and female sex (β = -6.3, 95% CI = -9.1 to -3.5, p <0.0001) were negative independent predictors of change in peak VO2 over 12 months, while CR attendance (β = 0.21, 95% CI = 0.0032-0.42, p = 0.047) and recommended exercise habit after the CR program (β = 2.1, 95% CI = 0.095-4.1, p = 0.040) were positive independent predictors of change in peak VO2 over 12 months. In female patients, exercise capacity improved during the CR program but decreased to AMI onset levels after 12 months.