Characteristics and Outcomes of Frail Patients with COVID-19 Admitted to ICU: An Individual Patient Data Meta-Analysis
Abstract Purpose: Frailty is often used in clinical decision-making for patients with COVID-19, yet studies have found variable influence of frailty on outcomes in those admitted to the intensive care unit (ICU). In this individual patient data meta-analysis, we evaluated the characteristics, and outcomes of frail patients admitted to ICU with COVID-19.Methods: We contacted the corresponding authors of sixteen eligible studies published between December 1st 2019 and February 28th 2021 reporting the clinical frailty scale (CFS) in patients with confirmed COVID-19 admitted to ICU. Individual patient data was obtained from 7 studies. We classified patients as non-frail (CFS=1-4) or frail (CFS=5-8). The primary outcome was hospital mortality. We also compared the use of mechanical ventilation (MV) and the proportion of ICU bed-days between frailty categories. Results: Of the 2001 patients admitted to ICU, 388 (19.4%) were frail. Increasing age and sequential organ failure assessment (SOFA) score, CFS ≥4, use of MV, vasopressors, renal replacement therapy and hyperlactatemia were risk factors for death in a multivariable analysis. Hospital mortality was higher in frail patients (65.2% vs. 41.8%; p<0.001), with adjusted mortality increasing with a rising CFS score beyond 3. Younger and non-frail patients were more likely to receive MV. Frail patients spent less time on MV (median days [IQR] 9 [5-16] vs. 11 [6-18]; p=0.012) and accounted for only 12.3% of total ICU bed-days. Conclusion: Frail patients with COVID-19 were commonly admitted to ICU and had greater hospital mortality but spent relatively fewer days in ICU when compared with non-frail patients. Frail patients receiving MV were at greater risk of death than non-frail patients. Systematic review registration: Registration protocol in PROSPERO (CRD42020224255).