RESUMEN
BACKGROUND: Although frailty has been associated with atypical manifestations of infections, little is known about COVID-19 presentations in hospitalized frail patients. We aimed to investigate the association between age, frailty, and clinical characteristics of COVID-19 in hospitalized middle-aged and older adults. METHOD: Longitudinal observational study comprising 711 patients aged ≥50 years consecutively admitted to a university hospital dedicated to COVID-19 severe cases, between March and May 2020. We reviewed electronic medical records to collect data on demographics, comorbidities, COVID-19 signs/symptoms, and laboratory findings on admission. We defined frailty using the Clinical Frailty Scale (CFS = 1-9; frail ≥5). We also documented in-hospital mortality. We used logistic regressions to explore associations between age, frailty, and COVID-19 signs/symptoms; and between typical symptoms (fever, cough, dyspnea) and mortality. RESULTS: Participants had a mean age of 66 ± 11 years, and 43% were female. Overall, 25% were frail, and 37% died. The most common COVID-19 presentations were dyspnea (79%), cough (74%), and fever (62%), but patients aged ≥65 years were less likely to have a co-occurrence of typical symptoms, both in the absence (OR = 0.56; 95% CI = 0.39-0.79) and in the presence of frailty (OR = 0.52; 95% CI = 0.34-0.81). In contrast, older age and frailty were associated with unspecific presentations, including functional decline, acute mental change, and hypotension. After adjusting for age, sex, and frailty, reporting fever was associated with lower odds of mortality (OR = 0.70; 95% CI = 0.50-0.97). CONCLUSIONS: Atypical COVID-19 presentations are common in frail and older hospitalized patients. Providers should be aware of unspecific disease manifestations during the management and follow-up of this population.