Correlation of the Brody high resolution computed tomography scoring system with aerobic fitness and lung function in patients with cystic fibrosis

Abstract

<b>Background:</b> Patients with cystic fibrosis (CF) present airway obstruction leading to permanent structural lung damage, which may contribute to the decline in lung function and exercise intolerance. <b>Aims:</b> To evaluate the correlation between the Brody tomographic scoring system with aerobic fitness and lung function variables. <b>Methods:</b> Cross-sectional study including patients with a diagnosis of CF aged ≥6 years. All subjects underwent lung function (spirometry), cardiopulmonary exercise testing (CPET), and a high resolution computed tomography test in order to calculate the Brody score, following the ATS/ERS recommendations. A Pearson correlation test was used for statistical purposes. The study was approved by a research ethics committee. <b>Results:</b> Nineteen patients (63,2% male), mean age 13.9±5.2 years, were included. A mean forced expiratory volume in the first second (FEV1) of 78.3±27.7%, peak oxygen consumption of 35.7±6.2 mL.kg-1.min-1 and Brody score of 42.0±26.7 were found, describing a sample of mild-to-moderate lung impairment. As for aerobic fitness, an inverse and moderate correlation was found between peripheral oxygen saturation at peak exercise and the Brody score (r=-0.57, p=0.01), indicating that patients with the worst tomographic score presented more desaturation during exercise. Lung function also correlated inversely and moderately with the Brody score (forced vital capacity: r=-0.48, p=0.04; FEV1: r=-051, p=0.03). <b>Conclusion:</b> The Brody score correlates with both oxygen desaturation at peak exercise and lung function, highlighting the influence of structural lung damage on lung function impairment and exercise intolerance.