Short Report PNEUMON Pneumon 2021;34(4):17 https://doi.org/10.18332/pne/143224 Published by European Publishing. © 2021 Cilloniz C. et al. This is an Open Access article distributed under the terms of the Creative Commons Attribution NonCommercial 4.0 International License. (http://creativecommons.org/licenses/by-nc/4.0) COVID-19 in patients aged 80 years and over during the peaks of the frst three pandemic waves at a Spanish tertiar hospital Catia Cilloniz 1 , Fernanda Meira 2 , Gerad Dueñas 2 , Julia V. Gimeno-Miron 2 , Mariana Chumbita 2 , Pedro Puerta-Alcalde 2 , Nicole Garcia-Pouton 2 , Albert Gabarrus 1 , Veronica Rico 2 , Antoni Torres 1 , Carolina Garcia-Vidal 2 , Alex Soriano 1 ABSTRACT 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 ver elderly patients with COVID-19 across three consecutive waves in Spain. METHODS We retrospectively evaluated ver elderly patients admitted with COVID-19 to a university hospital in Barcelona, Spain, across the three frst waves. Main outcomes were ICU admission and 30-day mortality. RESULTS From March 2020 to Februar 2021, 3105 patients diagnosed with COVID-19 were admitted. Of these, 655 (21%) were ver 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, respirator rate ≥25 breaths/min, LDH ≥337.5 U/L and C-reactive protein ≥11.5 mg/dL were signifcantly associated with ICU admission in the multivariable analysis. Overall, 30-day mortality was 34%. The ICU admission rate was signifcantly higher during the frst wave compared to the third wave (16% vs 8%; p=0.009), whereas no signifcant diferences 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 frst pandemic peaks. ICU admission more likely occurs in ver elderly male patients with higher respirator rate, with elevate LDH and C-reactive protein. Overall, our 30-day mortality rate was lower compared to other series globally. INTRODUCTION Since the beginning of the pandemic, Spain has been hit by fve waves of COVID-19. Age was widely used as a prioritizing criterion for ICU admission, which has been one of the most controversial aspects of the pandemic thus far 1 . Numerous studies have found older age to be associated with higher risk of severe illness, complications, and mortality in COVID-19 2 . Despite that patients aged ≥80 years have distinct clinical features and risk factors, notably multiple comorbidities and polypharmacy 3 , there is little information on this specifc population. We aimed to describe and compare the clinical characteristics, complications, therapy and outcomes in ver elderly patients with COVID-19 during the frst three waves of the pandemic in Spain. METHODS We retrospectively evaluated all consecutive very elderly patients admitted to Hospital Clinic, Barcelona (Spain). All patients admitted >48 h with a defnite diagnosis of COVID-19 (either confrmed by RT-PCR or fulflling clinical criteria in place) between March 2020 and Februar 2021 were included. The primary outcome was ICU mortality. Secondar outcomes included length of hospital stay, early mortality (within 5 days of admission), 30-day mortality and need for mechanical ventilation. We divided the study population into three groups for the analysis: first wave (March to June 2020), second wave (July to November 2020) and third wave (December 2020 to Februar 2021). Categorical variables were compared between the three groups using the χ 2 test, while continuous variables with the Kruskal-Wallis test. In the event of a signifcant overall test, we conducted post hoc pairwise comparisons with Bonferroni correction. We examined the association of risk factors with ICU admission using logistic regression models. Afer bivariate analyses, we selected independent variables at a p<0.25. All the variables were put into a multivariable logistic regression analysis model. Final variable selection was performed using the backward stepwise selection method, except for period, which had to appear in the model. The Hosmer–Lemeshow goodness-of-ft test was performed to assess the overall fit of the final model. The receiver AFFILIATION 1 Department of Pneumology, Hospital Clinic of Barcelona, Barcelona, Spain 2 Infectious Diseases Department, Hospital Clinic of Barcelona, Barcelona, Spain CORRESPONDENCE TO Alex Soriano. Department of Pneumology, Hospital Clinic of Barcelona, Villarroel 170, Barcelona 08036, Spain. E-mail: asoriano@clinic.cat ORCID ID: https://orcid. org/0000-0002-9374-0811 Catia Cilloniz. Department of Pneumology, Hospital Clinic of Barcelona, Villarroel 170, Barcelona 08036, Spain. E-mail: catiacilloniz@yahoo.com ORCID ID: https:// orcid.org/0000-0002-4646-9838 KEYWORDS outcomes, waves, pandemic, elderly, covid-19 Received: 4 September 2021 Revised: 29 September 2021 Accepted: 20 October 2021