Patients with idiopathic pulmonary fibrosis (IPF) complete and respond to pulmonary rehabilitation at rates similar to patients with chronic obstructive pulmonary disease (COPD), according to results of a real-world study. The findings reported in an article published in the journal CHEST® reinforce pulmonary rehabilitation’s benefits for this population.
A progressive decline in respiratory and physical function characterizes IPF, with median survival from diagnosis of 3-5 years, according to Claire Nolan, PhD, of Harefield Hospital, Middlesex, England, and colleagues. The effects of pharmacologic therapies on IPF on symptom burden and quality of life are modest, although lung function decline may be slowed. Supporting evidence for pulmonary rehabilitation benefit in IPF is more modest than it is for COPD, for which exercise capacity, dyspnea, and health-related quality of life improvement have been demonstrated.
“We did not design a randomized, controlled trial,” Dr. Nolan said in an interview, “as it was considered unethical by the local ethics committee to withhold pulmonary rehabilitation based on clinical guidance in the United Kingdom.” She pointed out that initial pulmonary rehabilitation trials in COPD included an intervention (pulmonary rehabilitation) and a control (standard medical care) arm.
The study aims were to compare the effects of pulmonary rehabilitation with real-world data between IPF and COPD with respect to magnitude of effect and survival. The authors’ hypothesis was that IPF patients would have a blunted response to pulmonary rehabilitation with reduced completion rates, compared with a matched COPD group, and with increased mortality.
Study details
Investigators use propensity score matching of 163 IPF patients with a control group of 163 patients with COPD referred to pulmonary rehabilitation. Completion rates, responses, and survival status were recorded for 1-year following pulmonary rehabilitation discharge. The 8-week outpatient program was composed of two supervised exercise and education sessions with additional unsupervised home-based exercise each week.
While spirometry data, as expected, showed a higher proportion of IPF patients using supplemental oxygen, pulmonary rehabilitation completion rates were similar for both groups (IPF, 69%; COPD, 63%; P = .24) and there was no between group difference in the number of sessions attended (P = .39). Medical Research Council (muscle strength) (MRC), incremental shuttle walk test (ISW), and Chronic Respiratory Questionnaire total score (CRQ-T) improved significantly in both groups, again with no significant difference between groups.
Over the study course, there was progressive, significant worsening of forced vital capacity percentage, predicted, prescription supplemental oxygen, resting peripheral oxygen saturation, exercise capacity, health-related quality of life and pulmonary rehabilitation adherence across groups of responders (n = 63; 38%), nonresponders (n = 50; 31%) and noncompleters (n = 50; 31%). Among the IPF patients, 6 died before completing pulmonary rehabilitation, with 42 (27%) dying during follow-up.
Benefits of rehabilitation
Multivariable analyses showed that noncompletion and nonresponse were associated with significantly higher risk of all-cause mortality at 1-year. Also, time to all-cause mortality was shorter (P = .001) for noncompleters and nonresponders, compared with completers. A trend toward higher completion rates in the IPF group, compared with the COPD group, may be explained, the researchers explained, by fewer hospitalizations over the prior 12 months in the IPF group.
“Although many programs are designed for people with COPD,” Dr. Nolan and colleagues concluded, “our study demonstrates that people with IPF have similar clinical benefits and completion rates to those with COPD. These data reinforce the importance of referral to and engagement in pulmonary rehabilitation amongst the IPF population.”
These findings, Dr. Nolan emphasized, emerged from a single center, and validation in other settings is needed.
This study was funded by a National Institute for Health Research Doctoral Research Fellowship (2014-07-089) and a Medical Research Council New Investigator Research Grant (98576).