COVID-19 in patients aged 80 years and over during the peaks of the first three pandemic waves at a Spanish tertiary hospital

INTRODUCTION COVID-19 disproportionately impacts patients aged >= 80 years, yet few studies have focused on this population. We aimed to investigate the clinical characteristics and outcomes of very elderly patients with COVID-19 across three consecutive waves in Spain. METHODS We retrospectively evaluated very elderly patients admitted with COVID-19 to a university hospital in Barcelona, Spain, across the three first waves. Main outcomes were ICU admission and 30-day mortality. RESULTS From March 2020 to February 2021, 3105 patients diagnosed with COVID-19 were admitted. Of these, 655 (21%) were very elderly patients, 50% were female and median age was 86 (83; 89) years. ICU admission and ICU-mortality rates were 11% and 42%, respectively; male sex, respiratory rate >= 25 breaths/min, LDH >= 337.5 U/L and C-reactive protein >= 11.5 mg/dL were significantly associated with ICU admission in the multivariable analysis. Overall, 30-day mortality was 34%. The ICU admission rate was significantly higher during the first wave compared to the third wave (16% vs 8%; p = 0.009), whereas no significant differences in 30-day mortality were found between waves (p = 0.107). CONCLUSIONS We observed an increase in the percentage of very elderly patients admitted to the ICU during the three first pandemic peaks. ICU admission more likely occurs in very elderly male patients with higher respiratory rate, with elevate LDH and C-reactive protein. Overall, our 30-day mortality rate was lower compared to other series globally.