Advanced age, comorbidity and the risk of mortality in COVID-19 infection

BACKGROUND: Advanced age and comorbidities have been described to increase the risk of mortality associated with COVID-19 infection. However, the degree to which comorbidities influence mortality among younger and older adults with and without comorbidity in COVID-19 infection has not been clearly elucidated. OBJECTIVE: To examine the impact of comorbidity on mortality among younger and older unvaccinated adults with COVID-19 infection admitted to a safety-net hospital. METHODS: This is a retrospective study in which 638 unvaccinated COVID-19 positive study participants admitted to a safety-net hospital between March 1, 2020, and August 31, 2020 were included. The risk of in-hospital mortality or referral to hospice (adverse outcome) was compared among younger and older participants with and without comorbidity. RESULTS: A total of 62 patients had adverse outcome while in the hospital (10%). Risk factors independently associated with adverse outcome included advanced age (OR(CI) 9.21 (2.29-37.06), p=.002), male sex (OR(CI) 2.6(1.34-5.16), p=.005), living in most disadvantaged area (OR(CI) 2.42(1.8-5.42), p=.03), history of diabetes (OR(CI) 2.35(1.12-4.95), p=.023), and history of heart failure (OR(CI) 4.00(2.09-7.63), p<.001). Further analysis after creating risk groups based on participants age and the presence of diabetes and / or heart failure was performed. The probability of adverse outcome was highest among older male participants with comorbidities (Pr =0.315 (CI: 0.176-0.454)). The probability of adverse outcome among older participants without diabetes and heart failure (Pr =0.081 (CI: .010 -0.152) was less than the probability for younger patients with diabetes and heart failure (Pr: 203 (CI: 0.103 – 0.303) CONCLUSIONS: While older adults with comorbidities were the most vulnerable for adverse outcome, the risk of adverse outcome among older adults without comorbidities was less than that of younger adults with comorbidities.