The association of typical and atypical symptoms on in-hospital mortality of older adults with COVID-19: a multicentre cohort study

Atypical disease presentations are common in older adults with COVID-19. The objective of this study was to determine the prevalence of atypical and typical symptoms in older adults with COVID-19 through progressive pandemic waves and the association of these symptoms with in-hospital mortality. This retrospective cohort study included consecutive adults aged over 65 years with confirmed COVID-19 infection who were admitted to seven hospitals in Toronto, Canada from March 1, 2020 to June 30, 2021. The median age for the 1786 patients was 78.0 years and 847 (47.5%) were female. Atypical symptoms (as defined by geriatric syndromes) occurred in 1187 patients (66.5%), but rarely occurred in the absence of other symptoms (n=106, 6.2%). The most common atypical symptoms were anorexia (n=598, 33.5%), weakness (n=519, 23.9%), and delirium (n=449, 25.1%). Dyspnea (adjusted odds ratio [aOR] 2.05, 95% confidence interval [CI] 1.62–2.62), tachycardia (aOR 1.87, 95% CI 1.14–3.04), and delirium (aOR 1.52, 95% CI 1.18–1.96) were independently associated with in-hospital mortality. In a cohort of older adults hospitalized with COVID-19 infection, atypical presentations frequently overlapped with typical symptoms. Further research should be directed at understanding the cause and clinical significance of atypical presentations in older adults.