Short Physical Performance Battery and Long Term Prognosis Following Severe Acute Exacerbation of COPD: a Prospective Cohort Study

Rationale: The Short Physical Performance Battery (SPPB; comprising standing balance, gait speed and sit-to-stand; score range 0-12) is a simple lower limb performance measure that is widely used in gerontology. In lung transplant candidates, lower SPPB scores are associated with greater disability and increased risk of delisting or death. We assessed the long-term predictive performance of the SPPB for mortality and readmission in patients hospitalized with severe acute exacerbations of COPD (AECOPD). Methods: The SPPB was measured on the day of discharge in 212 patients hospitalized with AECOPD (52% men; mean age 72 years; FEV1 35%predicted). Mortality and readmissions were recorded over a three year period after hospital discharge. We calculated hazard ratios (HR) using Cox proportional hazards regression, adjusting for age, sex, BMI, MRC Dyspnoea, FEV1 %predicted and co-morbidity burden. Results: During follow-up, we documented 74 (35%) deaths, and 157 (74%) of the cohort were readmitted. SPPB (per point increase) was independently associated with decreased all-cause mortality risk and all-cause readmission on multivariable analysis (HR 0.91 (95% CI 0.83 to 0.99); p=0.034 and 0.91 (95% CI 0.86 to 0.96); p=0.001 respectively). Conclusion: We propose that the SPPB, a simple functional test, provides additional prognostic information at discharge in patients hospitalized with AECOPD.