Association with chest CT measured pectoralis muscle area and outcomes of non-tuberculosis mycobacterial pulmonary disease

This study evaluated the prognostic value of PMA measured on chest CT in predicting the radiological progression of patients with NTM-PD. Analyzing 77 patients from 2018 to 2023, the radiological progression group showed significantly smaller PMA compared to the non-progression group. The AVIEW Metrics (Coreline Soft, Korea) software was utilized to perform automated threshold-based segmentation of the pectoralis muscle on axial chest CT slices at the mid-T4 level and calculate its area and density. Multivariable logistic regression revealed a significant negative association between PMA and NTM-PD progression after adjusting for confounders. Mediation analysis further confirmed that part of the PMA's effect is indirectly transmitted through FEV1. In conclusion, a small PMA is an independent risk factor for the radiological progression of NTM-PD, serving as an indicator of sarcopenia and respiratory muscle status. These findings highlight the potential of CT-derived body composition metrics as imaging biomarkers, linking muscle status with disease progression and pulmonary function. In this study, AVIEW Metrics software was utilized to automatically segment the pectoralis muscle and quantify its area and density, supporting reproducible assessment from routine chest CT.