Comparison of Functional Exercise Capacity, Muscle Oxygenation, Respiratory Muscle Strength, and Physical Activity Level in Pediatric Cystic Fibrosis and Primary Ciliary Dyskinesia
Comparison of Functional Exercise Capacity, Muscle Oxygenation, Respiratory Muscle Strength, and Physical Activity Level in Pediatric Cystic Fibrosis and Primary Ciliary Dyskinesia
Cystic fibrosis (CF) and primary ciliary dyskinesia (PCD) are genetic diseases characterized by chronic respiratory tract infections. In both diseases, impaired mucociliary clearance, recurrent respiratory infections, and persistent inflammation lead to progressive deterioration in respiratory function. This condition limits patients' activities of daily living, leading to physical inactivity and exercise intolerance. Functional exercise capacity in patients with CF and PCD is reduced due to increased respiratory load, musculoskeletal involvement, and nutritional deficiencies. In exercise tests involving the upper and lower extremities, both patient groups exhibited significantly lower performance compared to healthy individuals. Muscle oxygenation is particularly reduced in patients with cystic fibrosis and is associated with inadequate oxygen delivery to peripheral muscles, mitochondrial dysfunction, and increased muscle fatigue. Although studies on muscle oxygenation in PCD patients are limited, it is thought to be affected by similar pathophysiological mechanisms. Respiratory muscle strength is weakened in both patient groups due to chronic cough, hyperinflation, and increased respiratory effort. This is particularly evident in a significant decrease in inspiratory and expiratory muscle strength. The number of studies in the literature evaluating muscle oxygenation, respiratory muscle strength, and physical activity levels in patients with CF and PCD is limited. There are no studies comparing muscle oxygenation between patients with CF and PCD.
In patients with cystic fibrosis (CF) and primary ciliary dyskinesia (PCD), lower extremity exercise capacity, skeletal muscle function, respiratory muscle strength, and physical activity levels are limited by various pathophysiological mechanisms. In CF patients, lower extremity exercise capacity is significantly reduced due to ventilation limitation, respiratory muscle fatigue, and mitochondrial dysfunction. Early fatigue findings such as delayed oxygen uptake and lactate accumulation have been reported in lower extremity-specific exercise tests. In PCD patients, respiratory workload increases due to ventilation-perfusion mismatch and impaired mucociliary clearance, which can limit muscle oxygen utilization during exercise. Recent studies have shown that PCD patients have lower resting muscle oxygen saturation compared to healthy individuals, but these values are relatively maintained during exercise. In CF, respiratory muscle strength is weakened, particularly at the diaphragm and intercostal muscles, leading to a decrease in ventilatory reserve during exercise. Similarly, submaximal respiratory muscle fatigue and decreased inspiratory muscle strength have been reported in patients with PCD. Regarding physical activity levels, daily activity levels in both patient groups are significantly lower than in healthy peers, and this has been associated with disease progression, muscle dysfunction, and exercise intolerance. Objectively measured studies in children and adolescents with CF have reported that they fall below the recommended daily activity level, and this inadequacy negatively impacts muscle function over time. A similar tendency toward physical inactivity is also found in PCD patients, and this is considered directly related to exercise capacity. The number of studies in the literature evaluating muscle oxygenation, respiratory muscle strength, and physical activity levels in patients with CF and PCD is limited. There are no studies comparing muscle oxygenation in patients with CF and PCD. The aim of our study was to compare functional exercise capacity, muscle oxygenation, respiratory muscle strength, and physical activity in children with CF, PCD, and healthy children.
Inclusion Criteria:
Cystic fibrosis patients;
Primary ciliary dyskinesia patients;
Healthy controls;
Exclusion Criteria:
Patients;
Healthy controls;