Gender differences in response to center-based cardiac rehabilitation: a retrospective study

Abstract Background Cardiac rehabilitation (CR) is an effective secondary prevention measure after a cardiovascular intervention. Yet, uptake and adherence are low with marked differences between men and women. Purpose To investigate whether gender differences exist in adherence to, and in responses in physical fitness after completion of a standard exercise-based supervised CR program. Methods We retrospectively collected data from a Cardiac Rehabilitation database, which includes all patients enrolling in the cardiac rehabilitation program of a University Hospital. For the purpose of this study we included only patients who underwent percutaneous transluminal coronary angioplasty (PTCA) or percutaneous coronary intervention (PCI) between 2008 and 2023, enrolled for the first time in the CR program, and who completed follow-up assessments after completion of CR. The CR program incorporated three sessions of supervised aerobic and strength exercise per week for 12 weeks, followed by two sessions per week for the final 4 weeks. Adherence to the program was expressed as the number of weeks trained and the average training frequency per week. Differences in baseline characteristics and adherence were compared using unpaired t-tests or Wilcoxon signed rank tests, depending on the normality of the data. Differences in responses in physical fitness among gender were evaluated using a mixed model ANOVA. Outcome measures were peak oxygen consumption (pVO2), peak load, respiratory exchange ratio (RER), Borg-score, resting systolic and diastolic blood pressure (SBP and DBP), and BMI. Associations between adherence and changes in physical fitness were calculated using Pearson correlation coefficients. All analyses were performed using R-software version 4.3.1 and statistical significance was set at p0.05 for both main and interaction effects. Results A total sample of 1 395 patients (1 144 men and 251 women) were included. Baseline differences between men and women were found for resting SBP, pVO2, peak load, RER and Borg-score. As shown in Table 1, men and women completed a similar number of training weeks, though men participated in a significantly higher number of sessions per week (p0.05). A significant increase in exercise capacity (pVO2 and peak load) was observed in both men and women (p-time 0.001 for both), though the improvement was larger in men (p-interaction 0.001). Only low correlations were found between adherence and changes in physical fitness (Figure 1). Conclusions Men show a higher training frequency and larger improvement in exercise capacity after center-based CR, compared to women. These findings are in line with previously published studies. No strong correlation was found between training frequency and changes in physical fitness. As such, further investigation is needed to elucidate the determinants of the differences in response among men and women. Overview of gender differences. Correlation adherence and fitness.