Purpose: The aim of the study was to correlate computed tomographic (CT) scoring systems for pulmonary sarcoidosis with cardiopulmonary exercise testing and evaluate which scoring system provides the most reliable information for assessing disease severity and predicting impairment of gas exchange during exercise.
Materials and methods: The institutional review board approved this retrospective study. All 62 patients underwent thin-section CT, pulmonary function tests, and cardiopulmonary exercise test. Two observers scored CT images according to scoring systems published by Remy-Jardin and colleagues. Spearman rank correlation coefficients were calculated between CT patterns and pulmonary functional impairment parameters, and multiple regression analyses were performed to evaluate which CT abnormalities were significantly associated with pulmonary functional impairment parameters.
Results: Regardless of scoring system, PaO2max was significantly associated with the subscores of ground-glass opacity, linear opacity, and total CT scores. Multiple regression analyses showed that subscores of ground-glass and linear opacity in the Leung scoring system appeared to explain a significant amount of variance in functional parameters at rest and at maximal exercise.
Conclusions: CT findings, particularly ground-glass opacity and linear abnormalities, can explain a significant amount of variance in cardiopulmonary exercise parameters. This suggests that CT-based scoring systems are valid measures of disease severity in sarcoidosis.