Short Physical Performance Battery: Response to Pulmonary Rehabilitation and Minimal Important Difference Estimates in Patients With Chronic Obstructive Pulmonary Disease

Objective: To determine the response to a pulmonary rehabilitation (PR) program and minimal important differences (MIDs) for the Short Physical Performance Battery (SPPB) subtests and SPPB summary score in patients with chronic obstructive pulmonary disease (COPD). Design: Retrospective analysis using distribution-and anchor-based methods. Setting: PR center in the Netherlands including a comprehensive 40-session 8-week inpatient or 14-week outpatient program. Participants: A total of 632 patients with COPD (age, 65 +/- 8y; 50% male; forced expiratory volume in the first second=43% [interquartile range, 30%-60%] predicted). Interventions: Not applicable. Main Outcome Measure: Baseline and post-PR results of the SPPB, consisting of 3 balance standing tests, 4-meter gait speed (4MGS), and 5 -repetition sit-to-stand (5STS). The chosen anchors were the 6-Minute Walk Test and COPD Assessment Test. Patients were stratified according to their SPPB summary scores into low-performance, moderate-performance, and high-performance groups. Results: 5STS (Delta=-1.14 [-4.20 to-0.93]s) and SPPB summary score (Delta=1 [0-2] points) improved after PR in patients with COPD. In patients with a low performance at baseline, balance tandem and 4MGS significantly increased as well. Based on distribution-based calculations, the MID estimates ranged between 2.19 and 6.33 seconds for 5STS and 0.83 to 0.96 points for SPPB summary score. Conclusions: The 5STS and SPPB summary score are both responsive to PR in patients with COPD. The balance tandem test and 4MGS are only responsive to PR in patients with COPD with a low performance at baseline. Based on distribution-based calculations, an MID estimate of 1 point for the SPPB summary score is recommended in patients with COPD. Future research is needed to confirm MID estimates for SPPB in different centers. Archives of Physical Medicine and Rehabilitation 2021;102:2377-84 (c) 2021 The Authors. Published by Elsevier Inc. on behalf of The American Congress of Rehabilitation Medicine. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)

Automated summary

The study evaluated the response of COPD patients to a pulmonary rehabilitation program, finding improvements in 5STS and SPPB summary score post-PR. Patients with low baseline performance also showed significant improvements in balance and gait speed.