Short- and long-term response and baseline association to pulmonary rehabilitation in 1,539 COPD patients

<bold>Introduction:</bold> Pulmonary Rehabilitation (PR) is a key treatment for patients with COPD, yet only 50% exhibit a positive short-term response to PR, warranting further investigation into short- and long-term response determinants in real-world datasets. <bold>Aim:</bold> To explore patient proportions and baseline variables associated with achieving minimal important change (MIC) in physical function and patient-reported outcomes (PROMs) at 10 weeks and 1 year post-PR. <bold>Methods:</bold> Data from a PR database (2002–2019) at Copenhagen University Hospital Hvidovre were analyzed. COPD patients with complete data on one physical outcome and one PROM were included. Assessments included the 6-minute walk test (6MWT) or endurance shuttle walk test (ESWT) and the St. George’s Respiratory Questionnaire (SGRQ) or COPD Assessment Test (CAT). <bold>Results:</bold> A total of 1539 COPD patients (Mean±SD age 69±9 yr, 62% female, FEV₁ pred. 36±14%, ESWT 170±91 sec, 6MWT 282±104 m, SRGQ 55±17, CAT 19±7) were analyzed. At 10 weeks, 9% were full-responders, 25% responders, and 66% non-responders. At 1 year, percentages of non-responders increased to 72%. MIC response was maintained in 41% of full-responders and 49% of responders. Adjusted multinominal regression revealed that higher baseline ESWT was positively associated with full-response (OR: 1.002 [95% CI: 1.000;1.004]) and response (OR: 1.003 [95% CI: 1.001;1.004]) at 10 weeks, with similar findings 1-year post-PR. <bold>Conclusion:</bold> The majority of patients did not achieve a MIC after 10 weeks of PR, however 47% of the short-term responders maintained their gains at 1 year. Among baseline variables, higher baseline ESWT was significantly associated to short- and long-term response.