Prognostic impact of erector spinae muscle cross-sectional area in patients with pleuroparenchymal fibroelastosis

Abstract

Abstract Pleuroparenchymal fibroelastosis (PPFE) progresses slowly but sometimes relatively quickly, leading to decreased activities of daily living (ADL) and muscle weakness. Skeletal muscle atrophy and muscle weakness in patients with chronic obstructive pulmonary disease (COPD) may be caused by cachexia and are associated with reduced ADLs and increased risk of death. However, the association between skeletal muscle mass and the prognosis of patients with PPFE remains unknown. We retrospectively analysed the clinical significance of the erector spinae muscle cross-sectional area (ESMCSA), a skeletal muscle index, and predictors of mortality within 3 years in 51 patients with PPFE and 62 patients with COPD. Patients with PPFE had significantly lower ESMCSA than those with COPD, and lower ESMCSA (< 22.57 cm2) was associated with prognosis within 3 years (log-rank test; p = 0.006), whereas lower body mass index (BMI) showed no association. Multivariate analysis showed that ESMCSA was an independent predictor of mortality within 3 years in patients with PPFE (hazard ratio, 0.900; 95% confidence interval: 0.834–0.964, p = 0.003). These results suggest the importance of monitoring ESMCSA in patients with PPFE and that assessing skeletal muscle mass in patients with PPFE could be a more useful prognostic indicator than BMI.