Pascual-Dapena, AnaChillarón Jordan, Juan JoséLlauradó Cabot, GemmaArnau-Barrés, IsabelFlores-Le-Roux, Juana AntoniaLópez Montesinos, InmaculadaSorli Redó, M. LuisaMartínez-Pérez, Juan LuisGómez-Zorrilla, SilviaDu, JuanGarcía-Giralt, NataliaGüerri Fernández, Roberto2022-11-042022-11-042022Pascual-Dapena A, Chillaron JJ, Llauradó G, Arnau-Barres I, Flores J, Lopez-Montesinos I, et al. Individuals with higher CD4/CD8 ratio exhibit increased risk of acute respiratory distress syndrome and in-hospital mortality during acute SARS-CoV-2 infection. Front Med (Lausanne). 2022 Jun 23; 9: 924267. DOI: 10.3389/fmed.2022.9242672296-858Xhttp://hdl.handle.net/10230/54688Background: CD4/CD8 ratio has been used as a quantitative prognostic risk factor in patients with viral infections. This study aims to assess the association between in-hospital mortality and at admission CD4/CD8 ratio among individuals with acute SARS-CoV-2 infection. Methods: this is a longitudinal cohort study with data of all consecutive patients admitted to the COVID-19 unit at Hospital del Mar, Barcelona, Spain for ≥48 h between March to May 2020. The CD4+ CD8+ T-cell subset differentiation was assessed by flow cytometry at admission as well as a complete blood test. Patients were classified according to CD4/CD8 ratio tertiles. The primary outcome was in-hospital mortality and the secondary outcome was acute respiratory distress (ARDS). Results: a total of 338 patients were included in the cohort. A high CD4/CD8 ratio (third tertile) was associated with a higher in-hospital mortality [adjusted Cox model hazard ratio (HR) 4.68 (95%CI 1.56-14.04, p = 0.006), reference: second tertile HR 1]. Similarly, a high CD4/CD8 ratio (third tertile) was associated with a higher incidence of ARDS [adjusted logistic regression model OR 1.97 (95%CI 1.11-3.55, p = 0.022) reference: second tertile HR 1]. There was a trend of higher in-hospital mortality and incidence of ARDS in patients within the first tertile of CD4/CD8 ratio compared with the second one, but the difference was not significant. No associations were found with total lymphocyte count or inflammatory parameters, including D-dimer. Conclusion: CD4/CD8 ratio is a prognostic factor for the severity of COVID-19, reflecting the negative impact on prognosis of those individuals whose immune response has abnormal CD8+ T-cell expansion during the early response to the infection.application/pdfengCopyright © 2022 Pascual-Dapena, Chillaron, Llauradó, Arnau-Barres, Flores, Lopez-Montesinos, Sorlí, Luis Martínez-Pérez, Gómez-Zorrilla, Du, García-Giralt and Güerri-Fernández. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) http://creativecommons.org/licenses/by/4.0/. The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.info:eu-repo/semantics/articlehttp://dx.doi.org/10.3389/fmed.2022.924267ARDSCD4/CD8 ratioSARS-CoV-2MortalityPrognoseinfo:eu-repo/semantics/openAccess