Changes in Physical Performance and their Association with Health Related Quality of Life in a Mixed Non-ischemic Cardiac Population

Purpose: Exercise-based cardiac rehabilitation (CR) improves physical performance and healthrelated quality of life (HRQoL). However, whether improvements in physical performance are associated with changes in both generic and disease-specific HRQoL has not been adequately investigated in a non-ischemic cardiac population. Methods Patients who were ablated for atrial fibrillation, who underwent heart valve surgery or who were treated for infective endocarditis and who participated in one of three randomised control rehabilitation trials were eligible for the current study. Change in physical performance and HRQoL were measured before and after a 12-week exercise intervention. Physical performance was assessed using a cardiopulmonary exercise test, a 6-min walk test and a sit-to-stand test. HRQoL were assessed using the generic Short-Form-36 and the disease-specific HeartQoL questionnaire. Spearman’s correlation coefficient (rho) and linear regressions quantified the association between changes in physical outcome measures and changes in HRQoL. Results A total of 344 patients were included (mean age 60.8 (11.6) years and 77% males). Associations between changes in physical outcome measures and HRQoL ranged from very weak to weak (Spearman’s correlation coefficient = -0.056-0.228). The observed associations were more dominant within physical dimensions of the HRQoL compared to mental or emotional dimensions. Adjusted for sex, age and diagnosis changes in physical performance explained no more than 20% of the variation in the HRQoL. Conclusion Our findings show that the positive improvement in HRQoL from exercise-based CR cannot simply be explained by an improvement in physical performance.