A fuller picture of COVID-19 prognosis: the added value of vulnerability measures to predict mortality in hospitalised older adults

Background: Although coronavirus disease 2019 (COVID-19) disproportionally affects older adults, the use of conventional triage tools in acute care settings ignores the key aspects of vulnerability.

Objective: This study aimed to determine the usefulness of adding a rapid vulnerability screening to an illness acuity tool to predict mortality in hospitalised COVID-19 patients.

Design: Cohort study.

Setting: Large university hospital dedicated to providing COVID-19 care.

Participants: Participants included are 1,428 consecutive inpatients aged ≥50 years.

Methods: Vulnerability was assessed using the modified version of PRO-AGE score (0-7; higher = worse), a validated and easy-to-administer tool that rates physical impairment, recent hospitalisation, acute mental change, weight loss and fatigue. The baseline covariates included age, sex, Charlson comorbidity score and the National Early Warning Score (NEWS), a well-known illness acuity tool. Our outcome was time-to-death within 60 days of admission.

Results: The patients had a median age of 66 years, and 58% were male. The incidence of 60-day mortality ranged from 22% to 69% across the quartiles of modified PRO-AGE. In adjusted analysis, compared with modified PRO-AGE scores 0-1 ('lowest quartile'), the hazard ratios (95% confidence interval) for 60-day mortality for modified PRO-AGE scores 2-3, 4 and 5-7 were 1.4 (1.1-1.9), 2.0 (1.5-2.7) and 2.8 (2.1-3.8), respectively. The modified PRO-AGE predicted different mortality risk levels within each stratum of NEWS and improved the discrimination of mortality prediction models.

Conclusions: Adding vulnerability to illness acuity improved accuracy of predicting mortality in hospitalised COVID-19 patients. Combining tools such as PRO-AGE and NEWS may help stratify the risk of mortality from COVID-19.