TY - JOUR T1 - Complementing chronic frailty assessment at hospital admission with an electronic frailty index (FI-Laboratory) comprising routine blood test results JF - Canadian Medical Association Journal JO - CMAJ SP - E3 LP - E8 DO - 10.1503/cmaj.190952 VL - 192 IS - 1 AU - Hugh Logan Ellis AU - Bettina Wan AU - Michael Yeung AU - Arshad Rather AU - Imran Mannan AU - Catherine Bond AU - Catherine Harvey AU - Nadia Raja AU - Peter Dutey-Magni AU - Kenneth Rockwood AU - Daniel Davis AU - Samuel D. Searle Y1 - 2020/01/06 UR - http://www.cmaj.ca/content/192/1/E3.abstract N2 - BACKGROUND: Acutely ill and frail older adults have complex social and health care needs. It is important to understand how this complexity affects acute outcomes for admission to hospital. We validated a frailty index using routine admission laboratory tests with outcomes after patients were admitted to hospital.METHODS: In a prospective cohort of older adults admitted to a large tertiary hospital in the United Kingdom, we created a frailty index from routine admission laboratory investigations (FI-Laboratory) linked to data comprising hospital outcomes. We evaluated the association between the FI-Laboratory and total days spent in hospital, discharge to a higher level of care, readmission and mortality.RESULTS: Of 2552 admissions among 1750 older adults, we were able to generate FI-Laboratory values for 2254 admissions (88.3% of the cohort). More than half of admitted patients were women (55.3%) and the mean age was 84.6 (SD 14.0) years. We found that the FI-Laboratory correlated weakly with the Clinical Frailty Scale (CFS; r2 = 0.09). An increase in the CFS and the equivalent of 3 additional abnormal laboratory test results in the FI-Laboratory, respectively, were associated with an increased proportion of inpatient days (rate ratios [RRs] 1.43, 95% confidence interval [CI] 1.35–1.52; and 1.47, 95% CI 1.41–1.54), discharge to a higher level of care (odd ratios [ORs] 1.39, 95% CI 1.27–1.52; and 1.30, 95% CI 1.16–1.47) and increased readmission rate (hazard ratios [HRs] 1.26, 95% CI 1.17–1.37; and 1.18, 95% CI 1.11–1.26). Increases in the CFS and FI-Laboratory were associated with increased mortality HRs of 1.39 (95% CI 1.28–1.51) and 1.45 (95% CI 1.37–1.54), respectively.INTERPRETATION: We determined that FI-Laboratory, distinct from baseline frailty, could be used to predict risk of many adverse outcomes. The score is therefore a useful way to quantify the degree of acute illness in frail older adults. ER -