The association between clinical frailty and walking speed in older hospitalised medical patients: a retrospective observational study

Abstract

This study aims to further evaluate the use of the clinical frailty scale (CFS) by assessing its correlation with usual walking speed (UWS) in older medical inpatients. Methods Retrospective observational study in an English tertiary university hospital. We analysed all admission episodes of people admitted to the Department of Medicine for the Elderly wards during a 3-month period. We excluded those who died or had a CFS score of 9, indicating terminal illness. The CFS was recorded on admission and 6 meter UWS was measured on the day of hospital discharge. Other variables collected were: age, sex, the four-item version of the Abbreviated Metal Test (AMT4), and the Emergency Department Modified Early Warning Score. Results There were 1022 patients admitted over the study period, of which 741 met inclusion criteria and had both CFS and walking speed data available. Five hundred and seventy were able to mobilise at least 6 m. The median UWS was 0.33 (0.21–0.50) m/s. Logistic ordinal regression showed that lower CFS, being male and higher score in the AMT4 were associated with higher odds of being in a higher walking speed category (odds ratio for CFS after covariable adjustment: 0.57 [95% CI, 0.50 to 0.65]). Conclusions We observed a strong association between higher admission CFS and lower discharge UWS. This association was not explained by variation in age, sex, presence of cognitive impairment or illness acuity and provides further evidence that the CFS maybe a valid measure of frailty in acute clinical settings.