Variables Associated with 30-Day Mortality in Very Elderly COVID-19 Patients

Abstract

Background: Advanced age increases the risk for severe COVID-19. However, the risk factors for mortality from COVID-19 in very elderly patients (≥80-years-old) are unknown. Objective: Investigate the relationship of mortality with the clinical characteristics of very elderly COVID-19 patients. Materials and Methods: Very elderly patients who were hospitalized with COVID-19 from December 3, 2022 to January 1, 2023 were retrospectively examined. Sociodemographic and clinical variables were recorded and survival was recorded after 30 days. Results: We examined 181 patients (median age: 90.84 years; 114 older than 90 years). The median Barthel index was 30.69, and 55.8% of patients had severe or critical COVID-19 pneumonia. Forty-two patients (33.2%) received a high-flow nasal cannula or non-invasive ventilation, and only 4.4% received mechanical ventilation. The overall mortality was 35.9%, and there was no significant difference in mortality for the 80 to 90-year-old group and the over 90-year-old group (37.7% vs 32.8%, P=0.508). A multivariate analysis showed that the Barthel index (OR, 0.975; 95% CI, 0.962–0.989), serum creatinine (SCr) level (OR, 1.003; 95% CI, 1.000– 1.006), white blood cell (WBC) count (OR, 1.160; 95% CI, 1.056–1.276), D-dimer level (OR, 1.060; 95% CI, 1.009–1.113), and corticosteroid use (OR, 0.268; 95% CI, 0.124–0.582) were significantly and independently related to 30-day mortality. A binary classification model based on the multivariate analysis had good predictive value (area under the curve, 0.794). Conclusion: Very elderly COVID-19 patients have a high risk for mortality. The Barthel index, SCr, WBC count, D-dimer level, and corticosteroid use were independently associated with mortality.