Effects of 3 months of detraining following cardiac rehabilitation in patients with atrial fibrillation

BACKGROUND: Atrial fibrillation negatively impacts physical fitness and health-related quality of life. We recently showed that 3 months of physiotherapist-led exercise-based cardiac rehabilitation improves physical fitness and muscle function in elderly patients with permanent atrial fibrillation and concomitant diseases. Little is, however, known about the consequences for physical fitness, physical activity level, and health-related quality of life after ending the rehabilitation period. METHODS: Prospective 3 months follow-up study of 38 patients out of 40 eligible (10 women) who, as part of a randomized controlled trial, had completed a 3 months physiotherapist-led cardiac rehabilitation resulting in improved physical fitness,. In the current study, the participants were instructed to refrain from exercise for 3 months after completion of the rehabilitation period. Primary outcome measure was physical fitness measured as highest achieved workload using an exercise tolerance test. Secondary outcome measures were muscle function (muscle endurance tests), physical activity level (questionnaire and accelerometer), and health-related quality of life, (Short Form-36), as in the preceding intervention study. We used the Wilcoxon Signed Rank test to analyse differences between the end of rehabilitation and at follow-up. The effect size was determined using Cohen's d . RESULTS: Exercise capacity and exercise time significantly decresead between end of rehabilitation and at follow-up (p < .0001 for both). A significant reduction in shoulder flexion repetitions (p = .006) was observed as well as reduced health-related quality of life in the Short Form-36 dimensions Physical Function (p = .042), Mental Health (p = .030), and Mental Component Score (p = .035). There were, however, no changes regarding objective and subjective physical activity measurements. CONCLUSION: In older patients with permanent atrial fibrillation, previously achieved improvements from physiotherapist-led exercise-based cardiac rehabilitation in physical fitness and muscle function were lost, and health-related quality of life was impaired after ending the rehabilitation period. A strategy for conserving improvements after a rehabilitation period is essential.