Computed Tomography morphometric analysis of patients with Idiopathic Inflammatory Myopathy related Interstitial Lung Disease correlates with Forced Vital Capacity

Title: Computed Tomography morphometric analysis of patients with Idiopathic Inflammatory Myopathy related Interstitial Lung Disease correlates with Forced Vital Capacity
Author(s): O’Mahony A1, Henry P3, Coughlan P2, Crowley C1, Ryan D1, Moore N1, O’Connor OJ1, Maher M1, Henry MT2 1. Academic Department of Radiology, Cork University Hospital / University College Cork 2. Department of Respiratory Medicine, Cork University Hospital / University College Cork 3. School of Medicine, University College Cork
Institution: CUH/UCC
Poster: Click to view poster
Category: ILD
Abstract: Sarcopenia is a prognostic indicator in COPD and IPF. Identification of sarcopenic patients may enable intervention to improve prognosis. Interstitial lung disease (ILD) is the most common non-musculoskeletal manifestation of patients with Idiopathic Inflammatory Myopathies (IIMs). This study investigated muscle mass in IIM, and its relationship to ILD disease severity.

IIM patients with ILD attending Cork University Hospital were identified. Morphomic analysis of muscle mass on CT thorax was performed using CoreSlicer, a web-based tool which enables semi-automated segmentation of muscle and fat. Bilateral Erector Spinae Muscle (ESM) and Pectoralis Muscle (PM) cross-sectional areas (CSA) were calculated. All morphomic data were correlated with lung function including forced vital capacity (FVC).

Data from 31 patients (16 male, mean age 69.8 years) were analysed. No relationship was established between change in morphomics between diagnostic (first) and second CT scans and change in PFTs over the same interval.

There were significant correlations between baseline and follow-up PM CSA, ESM CSA and FVC (p=0.002 r=0.384, p=0.013, r=0.318 respectively) when treated as separate data points. A negative relationship between the patients’ albumin levels and their visceral fat at T12 was also found (p=0.022, r=0.0215).

ESM CSA and PM CSA may be an important parameter in patients with IIM related ILD due to their significant correlations with FVC.