Functional, Clinical, and Sociodemographic Variables Associated with Risk of In-Hospital Mortality by COVID-19 in People over 80 Years Old

OBJECTIVES: The objective is to assess the role of functional, clinical, and analytic parameters in predicting mortality in older patients hospitalized due to COVID-19. DESIGN: Cohort study with a mean follow-up of 12.8 days. SETTING: Public university hospital (Madrid, Spain). PARTICIPANTS: 499 patients 80 and above consecutively admitted to a Spanish public university hospital between 4 March 2020 and 16 May 2020. MEASUREMENTS: Mortality was the main outcome. Data of sociodemographic variables (age, sex, living), comorbidities, polypharmacy, functional status, date of hospital admission and length of stay was recorded. Clinical symptoms, laboratory and X-ray findings were collected at time of admission. For multivariant analysis, logistic regressions were performed to identify risk factors for death. RESULTS: Mean age was 86.7±4.4 with 37% of death. Mortality was associated with male gender [odds ratio (OR) 1.50; 95% confidence interval (CI) 1.01–2.24], with a 5-points increase on Barthel Index [OR 1.01 (95%CI 1.00–1.02)], higher Charlson Index score [OR 1.13 (95%CI 1.02–1.26)] and comorbidities [OR 1.28 (95%CI 1.06–1.53)], hyperpolipharmacy [OR 2.00 (95%CI 1.04–3.82)], unilateral pneumonia [OR 1.83 (95%CI 1.01–3.30)], higher levels of C-reactive protein [OR 1.09 (95%CI 1.06–1.12)] and creatine [OR 1.48 (95%CI 1.15–1.89)]. Higher oxygen levels were a protective factor [OR 0.92 (95%CI 0.89–0.95)]. CONCLUSIONS: Functional status, being male, a higher burden of comorbidities, hyperpolipharmacy, unilateral pneumonia and some laboratory parameters predict in-hospital mortality in this older population. The knowledge of these mortality risk factors should be used to improve the survival of older hospitalized patients.