Sex differences in the change in cardiorespiratory fitness and additional physical and mental health outcomes after exercise training in adults with atrial fibrillation: a systematic review protocol

Background Patients with atrial fibrillation (AF), the most common sustained cardiac arrhythmia, often have a low cardiorespiratory fitness (CRF) and poor physical and mental health due to disabling AF symptoms. This is more pronounced in females, who also report worse AF symptoms and quality of life (QoL) than males. Improving CRF through exercise training is an important AF management target associated with lower hospitalization and mortality rates. Emerging research suggests smaller CRF improvements in females than males following the same exercise training program. Yet, this has not been systematically reviewed in the AF population. The primary purpose of this systematic review is to compare changes in CRF following exercise training between females and males with AF. Secondary aims will compare changes in AF symptoms, QoL and additional physical and mental health outcomes between sexes. Methods We will adhere to the reporting guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) statement. Five electronic bibliographic databases are being searched to identify studies with prospective cohort and experimental designs, implementing exercise training of any form (e.g. aerobic, strength) for at least 4 weeks, in adults (≥18 years old) with an AF diagnosis. Eligible studies must report a baseline and follow-up measure of at least one primary or secondary outcome. CRF (primary outcome) can be estimated or directly measured as peak oxygen consumption (VO 2 peak). When eligible results are not segregated by sex, authors will be contacted to obtain sex-specific data. Study quality and risk of bias will be assessed using the Tool for the assEssment of Study qualiTy and reporting in EXercise (TESTEX) scale and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Meta-analyses will be conducted to synthesize the measures of effect in studies with sufficient homogeneity. Discussion This review will address the lack of sex-based analyses in exercise studies in the AF population. By using a sex lens, we will provide evidence on the physical and mental health effects of exercise training in females and males with AF. Our findings will be of value to patients with AF, researchers and healthcare providers involved in AF management. Systematic review registration PROSPERO #CRD42022302310