Relationship of respiratory muscle strength, pulmonary function, and functional capacity with quality of life in patients with atrial fibrillation

Objective To examine the relationship of pulmonary parameters and functional capacity with quality of life (QoL) in patients with atrial fibrillation (AF). Methods Thirty-six patients with chronic AF were included in this cross-sectional study. QoL was assessed with the Medical Outcomes Survey 36-item Short Form (SF-36) and Minnesota Living with Heart Failure Questionnaire (MLHFQ). Respiratory muscle strength and pulmonary function were also measured. Functional capacity was assessed with the 6-min walk test (6MWT). The Borg CR10 Scale was used to determine the resting dyspnea and fatigue levels. Results The SF-36 physical component summary score was correlated with the maximum inspiratory pressure (r=0.517), maximum expiratory pressure (r=0.391), 6MWT distance (r=0.542), resting Borg dyspnea score (r=-0.692), and resting Borg fatigue score (r=-0.727). The MLHFQ total score was correlated with the maximum inspiratory pressure (r=-0.542), maximum expiratory pressure (r=-0.384), 6MWT distance (r=-0.535), resting Borg dyspnea score (r=0.641), and resting Borg fatigue score (r=0.703). The resting Borg fatigue score was the significant independent predictor of the SF-36 physical component score and the MLHFQ total score. Conclusion Respiratory muscle strength, functional capacity measured with the 6MWT, and resting symptoms including dyspnea and fatigue may have an impact on QoL in patients with AF.