Background: Limited evidence exists regarding the effectiveness of pulmonary rehabilitation (PR) within interstitial lung disease (ILD). Oxygen is frequently prescribed for these patients but has not been explored in the context of PR. The aim of this study was to compare short-term outcomes of PR and 2-year mortality in patients with ILD, who use home oxygen against those without oxygen.
Methods: Using an observational cohort design and principles of comparative effectiveness research, data were collected from patients with ILD referred for a 7-week outpatient PR program. Hospital notes were reviewed, oxygen use was documented, and survival status was recorded at 2 years. Exercise capacity and quality of life were measured at baseline and discharge from PR.
Results: One hundred fifteen patients were identified (96 with idiopathic pulmonary fibrosis); 43 used oxygen and 72 were nonoxygen users. Nonoxygen users improved their Incremental Shuttle Walk Test more than oxygen users (P < .05). Significant improvements were found after PR for nonoxygen users (Incremental Shuttle Walk Test 39.0 ± 54.3 m, Endurance Shuttle Walk Test 319 ± 359 seconds, Chronic Respiratory Questionnaire (CRQ)-Dyspnea 0.74 ± 0.94, CRQ-Fatigue 0.73 ± 1.15, CRQ-Emotion 0.61 ± 0.98, CRQ-Mastery 0.55 ± 1.01), whereas only Endurance Shuttle Walk Test (197 ± 287 seconds) improved for oxygen users (P < .05). Significant differences were found in survival rates between the 2 groups, 2 years after initial PR assessment (hazard ratio, oxygen users vs nonoxygen users: 2.7 [95% CI = 1.41 - 4.98], P = .002).
Conclusions: Oxygen users gain less from PR and have a higher mortality rate than nonoxygen users. These results should be used to aid discussion between patients and clinicians regarding referral to PR and the anticipated benefits.