Short Physical Performance Battery: Response to pulmonary rehabilitation and MCIDs in patients with COPD

Abstract

<b>Background:</b> The Short Physical Performance Battery (SPPB) is commonly used in patients with chronic obstructive pulmonary disease (COPD) to assess mobility and balance. However, information about the response to pulmonary rehabilitation (PR) and minimal clinical important differences (MCIDs) of SPPB subtests and summary score in these patients is limited. <b>Aim:</b> To determine the response to PR and MCIDs for the SPPB subtests and SPPB summary score in patients with COPD. <b>Methods:</b> Retrospective analysis of 632 patients with COPD (age: 65±8 years, 50% male, FEV1: 43 (27-47)% predicted) following a PR program was performed. The SPPB consisted of three balance standing tests, 4-meter gait speed (4MGS) test and 5-repetition sit-to-stand (5STS) test. MCIDs were estimated with anchor-based (anchors: COPD Assessment Test and 6-minute walk test) and distribution-based methods. <b>Results:</b> 5STS (∆=1.14 (-4.20- -0.93) sec) and SPPB summary score (∆=1 (0-2) points) improved significantly after PR. Anchor-based method could not determine MCIDs as there were no significant correlations between the anchors and SPPB scores. Based on distribution-based calculations, the MCID estimates range between 0.51-0.67 sec for balance side-by-side, 0.64-0.78 sec for semi-tandem, 1.80-2.03 sec for tandem, 0.05-0.31 m/s for 4MGS, 2.19-6.33 sec for 5STS and 0.81-0.96 points for SPPB summary score. <b>Conclusions:</b> The 5STS and SPPB summary score are both responsive to PR in patients with COPD. Based on distribution-based calculations, a MCID estimate of 1 point for the SPPB summary score is recommended in these patients. Future research is needed to confirm MCID estimates for the SPPB subtests in different centres.