Computed tomography morphomics and antifibrotic therapy in idiopathic pulmonary fibrosis
A T O'Mahony1, M G Waldron1, P J Henry2
1Department of Radiology, Cork University Hospital, Cork, Ireland.
Aim:
Idiopathic pulmonary fibrosis (IPF) is a debilitating and fatal lung disease. Changes in body composition potentially correlate with outcomes in patients with IPF.
Materials And Methods:
Patients with IPF on antifibrotic treatment attending a single institution were identified and retrospectively evaluated (n=84). Three groups were formed based on antifibrotic treatment: pirfenidone group, nintedanib group and pirfenidone-nintedanib switch group. Morphomic analysis of muscle quantity (cross-sectional area in cm2) and quality (density in Hounsfield Units) on thoracic computed tomography (CT) was performed using a web-based morphomic segmentation tool. Bilateral erector spinae and pectoralis muscles were measured at pre-defined vertebral levels.
Results:
All three treatment groups showed a statistically significant decline in forced vital capacity (FVC), diffusion capacity of the lung for carbon monoxide (DLCO), pectoral muscle cross sectional area (PMA), and erector spinae muscle cross-sectional area (ESMA). Muscle density did not change significantly. Differences existed in analytic morphomics between treatment groups. Patients with a pretreatment body mass index (BMI) below 30 were found to have a significantly greater loss of PMA when treated with nintedanib instead of pirfenidone. FVC and DLCO did not differ between treatment groups.
Conclusion:
There were no direct correlations between pulmonary function and morphomic parameters in our entire group of IPF patients. However, between different treatment groups, the rate of muscle bulk loss differed. This is an important consideration for clinicians when deciding on an antifibrotic agent of choice.
