Abstract
BACKGROUND: Coronavirus disease 2019 (COVID-19) represents the greatest health crisis of our times; it was declared by WHO a pandemic in March 2020. The risk of presenting a severe disease is inter-individual, since it varies according to age, comorbidities, and immunological status, in addition to the type of SARS-CoV-2 variant. The neutrophil/lymphocyte ratio (NLR) and lactic dehydrogenase (LDH) are widely used markers to assess the severity and predict the course of the disease in patients with COVID-19, with a direct relationship of higher value-worse prognosis. OBJECTIVE: To verify if the LDH-neutrophil-lymphocyte index calculated from laboratory tests taken within the first 24 hours of admission is useful as a predictor of 28-day mortality in adult patients diagnosed with COVID-19. MATERIAL AND METHODS: Retrospective and analytical cohort study. All consecutive patients over 16 years of any gender, admitted to a tertiary care center from March 2020 to March 2021, who had a diagnosis of COVID-19 with a positive PCR for SARS-CoV-2, were included. RESULTS: Higher levels of the LDHNL index were associated with higher mortality in patients hospitalized for COVID-19 (Q2 vs. Q1: RR 1.52 [1.24-1.87], p < 0.05; Q3 vs. Q1: RR 1.87 [1.55-2.25], p < 0.05; and Q4 vs. Q1: RR 2.74 [2.22-3-39], p < 0.05). CONCLUSIONS: The serum LDHNL index taken in the first 24 hours of admission can help to predict early the risk of mortality in hospitalized patients with COVID-19.