Pulmonary Rehabilitation Improves Survival in COPD

Oral presentation: Monday, May 21, 3:25 p.m.Mini-symposium: 2:00-4:30 p.m.Location: Room 3020-3022 (West Building, Level 3), Moscone Center

Pulmonary Rehabilitation and Improvement in Exercise Capacity Improves Survival in COPD

Newswise — ATS 2012, SAN FRANCISCO – Pulmonary rehabilitation and improvement in exercise capacity significantly improves survival in patients with chronic obstructive pulmonary disease (COPD), according to a new study from the UK.

“While the short- and medium-term benefits of pulmonary rehabilitation in COPD patients have been shown, its effects on survival have not been studied,” said lead author Johanna Williams, MSc, a researcher at the Department of Respiratory Medicine at the University Hospitals of Leicester NHS Trust. “Our analysis shows that completion of pulmonary rehabilitation and a higher level of response in exercise capacity is associated with a significant survival advantage in COPD patients.”

The results will be presented at the ATS 2012 International Conference in San Francisco.

Of 1,615 patients with COPD in the observational cohort study, 55.4% completed pulmonary rehabilitation. Subjects who completed pulmonary rehabilitation (n = 895), compared with those who did not (n = 720), had significantly higher mean incremental shuttle walking test (ISWT) scores at baseline. Kaplan Meier (KM) survival analysis revealed that there was a statistically significant survival advantage for those who completed rehabilitation when compared with those who didn’t complete (p<0.001 by the log rank test).

“These results should be interpreted with caution however,” said Ms. Williams “as improved survival is unlikely to be simply a result of completion of rehabilitation but also probably reflects that the sickest patients may be unable to complete and/or may have more co-morbidities so are more likely to die sooner”.

For those patients that did complete rehabilitation, 56.3 percent improved by more than 48m, the minimum clinically important difference (MCID) for the ISWT, and were considered responders. After adjustment for a number of prognostic factors including baseline ISWT, survival analysis showed that these responders had a significantly improved survival compared with non-responders (p<0.001 by the log rank test). “It should be remembered however that it is currently unknown whether other factors (possibly genetic) may influence a better training response and thus may be also associated with improved survival” said Ms. Williams.

“Our study shows that pulmonary rehabilitation and the magnitude of response in exercise tolerance following pulmonary rehabilitation in patients with COPD is associated not only with short-term improvements, but possibly also with improved survival,” said Ms. Williams. “COPD patients should be encouraged to exercise.”

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“Magnitude Of Improvement In Exercise Tolerance Following Pulmonary Rehabilitation Predicts Survival: A Long Term Observational Study” (Session B97, Monday, May 21, 3:25 p.m., Room 3020-3022, Moscone Center; Abstract 27501)

* Please note that numbers in this release may differ slightly from those in the abstract. Many of these investigations are ongoing; the release represents the most up-to-date data available at press time.

Abstract 27501Magnitude Of Improvement In Exercise Tolerance Following Pulmonary Rehabilitation Predicts Survival: A Long Term Observational StudyType: Scientific AbstractCategory: 15.05 - Pulmonary Rehabilitation: Outcomes (PR)Authors: J.E.A. Williams, R.H. Green, S.J. Singh; University Hospitals of Leicester NHS Trust - Leicester/UK

Abstract BodyIntroduction: Pulmonary Rehabilitation (PR) has been shown to improve a range of important outcomes in the short to medium term. What is not known is whether PR may also influence survival. We set out to conduct a survival analysis on a cohort of patients with COPD who had been assessed for PR during an 11 year period, with survival status ascertained for the entire data set in March 2010. Method: We conducted Kaplan Meier (KM) survival analysis for those patients who completed PR and those who dropped out as well as t tests to determine any baseline differences between the groups. For those who completed PR we then divided the group into those who improved by more than 48m, the minimum clinically important difference (MCID) for the incremental shuttle walking test (ISWT) - termed ’responders’ and those whose magnitude of improvement was <48m - ’non responders’. We ran T-tests to determine any baseline differences between responders and non responders as well as KM survival analysis. Cox regression was used to identify if magnitude of response to PR was able to predict survival. Results: 1615 patients with COPD were included in the initial analysis, of which 55.4% completed PR. Patients who completed PR had a significantly higher mean baseline ISWT score than non completers (190m vs 156m, p<0.0001). KM surival analysis found significant survival differences between completers and non-completers (log rank test, p<0.001). Of patients who completed PR, 56.3% improved more than the MCID (‘responders’). Fig 1 illustrates the KM survival analysis which shows a significant difference between responders and non-responders (p<0.001 by the log rank test) in favour of those who improved by more than 48m following PR. Cox regression determined that change in ISWT following PR independently predicted survival when corrected for i-BODE factors (FEV1%predicted, MRC grade, BMI and baseline ISWT) age and pack years smoked. Conclusion: This observational cohort analysis has shown that completion of PR and a higher magnitude of response in improvement in exercise capacity confers a significant survival advantage in patients with COPD. If patients can be encouraged to exercise, for some it may literally be a matter of life and death.

Funded by: None reported