A Sex-Based Examination of the Acute and Chronic Effects of Exercise Training on Physical and Mental Health Outcomes in Patients with Atrial Fibrillation

Abstract

Aims and Methods: This dissertation provides insights into the role of sex in the acute and chronic effects of exercise training (ET) in adults with atrial fibrillation (AF). Study 1 used a randomized crossover design to compare short-term changes in AF symptoms between females (F) and males (M) with symptomatic non-permanent AF, when they engaged in one week of high-intensity interval training (HIIT), moderate-intensity continuous training (MICT) or non-exercise Control. Studies 2 and 3 used data from two randomized controlled trials in patients with persistent and permanent AF. Study 2 cross-sectionally compared physical and mental health characteristics between sexes, whilst Study 3 examined sex differences in the effects of 12 weeks of HIIT or MICT on such outcomes. Study 4 was a systematic review comparing changes in physical and mental health outcomes following ET between sexes. Results: Study 1 enrolled 17 (35% F) patients. The preliminary findings showed that the overall symptom severity did not significantly differ across study conditions or sex. Study 2 included 78 (50% F) patients. Females had a 27% lower peak aerobic power (V̇O₂ₚₑₐₖ), and greater palpitations and resting heart rate. Study 3 included 111 (31% F) patients. Improvements in V̇O₂ₚₑₐₖ (F: +18%, M: +11%) and most outcomes (e.g., quality of life, functional capacity, heart rate, anxiety, depression) did not differ by sex. Study 4 included sex-specific exercise data from 18 studies (868 patients, 29% F). Changes in V̇O₂ₚₑₐₖ following ET did not differ between sexes. AF severity, general health and systolic blood pressure improved significantly less in females after ET. Conclusions: (i) exercise does not appear to worsen AF symptoms in the short term; (ii) some sex differences in palpitations and physical health were noted; (iii) improvements in V̇O₂ₚₑₐₖ and several patient-reported and health measures did not differ by sex following ET, yet, our meta-analyses showed that several health outcomes did not improve as much in females as in males following ET; and, (iv) future exercise trials in patients with AF must improve the representation of females.