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Updated: Jul 17, 2025

Author Spotlight: Unraveling the Impact of Mechanical Ventilation on Diaphragm Function and Patient Outcomes
Published on: November 3, 2023
Relationship of muscle thickness, strength, and diaphragm function in adults with cystic fibrosis
Nazlı Zeynep Uslu1, Derya Kocakaya1, Şehnaz Olgun Yıldızeli1
1Pulmonary Medicine, Marmara University Medical Faculty, Istanbul, Türkiye.
Objectives:
This study aimed to evaluate the muscle thickness, strength, and diaphragmatic function and relate them with clinical findings.
Patients And Methods:
The cross-sectional study was conducted with 54 participants (27 males, 27 females; mean age; 24.5±5.3 years; range, 18 to 45 years) between January 2017 and October 2017. Of the participants, 31 were adult CF patients, and 23 were age-and sex-matched controls. Patient demographics, 6-min walk distance, body mass index (BMI), and fat-free mass index (FFMI) were evaluated. Each patient underwent pulmonary function tests. Quadriceps femoris thickness and diaphragm thickening fraction were assessed by ultrasonography. Upper extremity strength was measured with a handheld dynamometer.
Results:
There was no difference between the patients' and controls' BMI (p=0.052). However, patients' FFMI was lower than the controls' (p=0.010). The FFMI correlated with pulmonary function tests. Patients' both right and left quadriceps femoris muscles were thinner than the controls (p=0.001 and p=0.001, respectively). Patients with pancreatic insufficiency had thinner muscles than patients without pancreatic insufficiency. The control group had a stronger handgrip than CF patients (33.5±10.1 vs. 24.5±9.2 kg, p=0.003).
Conclusion:
Peripheral muscle wasting and weakness and lower functional capacity are highly prevalent in CF patients.
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