Etiology and Level of Lung Derangement Do Not Affect the Beneficial Effect of Pulmonary Rehabilitation in Patients with Interstitial Lung Diseases

A growing body of literature suggests that comprehensive Pulmonary Rehabilitation (PR) improves symptoms and functional capacity also in patients with Interstitial Lung Disease. Aim of this study was to investigate whether the baseline level of functional capacity or lung derangement, and ILD etiology may predict and affect outcomes’ response to PR in these patients. MATERIALS AND METHODS Patients with ILD of different etiology were referred and prospectively admitted to PR, delivered according to a standardized protocol. Spirometry, Diffuse Lung Capacity for Carbon Monoxide [DLCO], incremental cyclo-ergometry test, Six Minutes Walking Distance Test [6MWDT], questionnaires on dyspnea and quality of life (St. George Respiratory Questionnaire-SGRQ, 5-point Medical Research Council scale-MRC) were assessed pre- and post- rehabilitation course; change from baseline of any measured variables was considered to assess the impact of PR on functional capacity, perceived symptoms and quality of life, respectively. Patients were stratified according to their level of DLCO, Forced Vital Capacity (FVC), 6MWTD, etiology (IPF or non-IPF), and GAP index (in IPF patients only). Analyses of changes from baseline and correlation test were conducted as appropriate. RESULTS Thirty-nine patients (mean age 66.87 ± 10.9 ys, IPF 62.5%) were enrolled and completed the PR course. 6MWDT (+54.3m, 95%CI 34.9-73.7, p < .0001), cycling time (+ 70.0%, p = .0009) and power (+60.4%, p= .008), iso-time dyspnea (-33.1%, p < .0001) and limb fatigue (-40.8%, p < .0001), SGRQ, MRC (p < .0001) significantly improved over time. Patients with lower baseline 6MWD showed greater change in 6MWD (Pearson r score = - .359, p = .034) and symptoms relief at SGRQ (r = -.229, p = .038). Different levels of FVC, DLCO, GAP index and etiology did not correlate with functional and symptoms outcomes. CONCLUSION Present study confirms that comprehensive rehabilitation is effective in patients with ILDs of different severity, and etiology and that baseline walking capacity inversely correlates with functional and symptom changes. Lung derangement or etiology does not affect outcomes following rehabilitation.