Pulmonary rehabilitation (PR) is prescribed to improve functional status of patients with chronic obstructive pulmonary disease (COPD) in settings of inpatient (IR) and outpatient rehabilitation (OR). In this study, we compared the effects of PR on all-cause mortality and hypothesized that patients in OR will have better chance of survival than those in IR.
Method: Setting-HEALTHSOUTH pulmonary rehabilitation program (HSPRP) in Richmond, Va.
Population: COPD patients without cancer who completed PR for the first time at HSPRP between 1995 and 2006.
Primary Analysis: Comparison of mortality adjusted for age and baseline 6-minute walk (6MW) in IR and OR groups.
Secondary Analysis: Comparison of mortality adjusted for age and baseline 6MW in subgroups of IR patients divided according to the degree of 6MW improvement in meters (m) after PR.
Results: Two hundred thirty-one completed OR, and 1,041 IR. Primary analysis did not detect significant difference in all-cause mortality between IR and OR groups with our sample size (median survival month of 47.0 months in OR and 39.0 months in IR, hazard ratio 1.21, 95% CI 0.94-1.55, P = .130). Among IR patients, one third (Group 1, n = 343) had less than 180 m improvement in 6MW after PR, other third (Group 2, n = 346), between 180 m and 350 m, and another third (Group 3, n = 352), greater than 350 m. Secondary analysis of these IR subgroups showed that larger improvement in 6MW correlated significantly with better median survival months among IR patients (Group 1: 32.2 months, 95% CI 27.4-36.6, Group 2: 40.2 months, 95% CI 35.0-49.1, Group 3: 58.9 months, 95% CI 48.2-71.0).
Conclusion: Magnitude of improvement in 6MW after PR predicts all-cause mortality among PR patients in the setting of IR.