Abstract
This study primarily aimed to examine the significance of the C-reactive protein to lymphocyte ratio (CLR), a key marker of inflammation, in relation to the disease progression and management of COVID-19 patients admitted to the intensive care unit (ICU). A total of 464 patients aged 18 years or older, diagnosed with COVID-19 and admitted to the ICU between April 1, 2021, and February 1, 2022, were included in the study. Sociodemographic, laboratory, radiological, and clinical data were collected for each patient. The cohort was then divided into two groups-those who survived and those who did not-and analyzed accordingly. Among the patients included in the study, 58.2% were male, and the mean age was 62.39 ± 15.65 years. The mortality rate was 42%. The analysis revealed that the need for high-flow oxygen and mechanical ventilation increased the risk of death by 9.64 times. Furthermore, for each 1-point increase in the SOFA Score, Charlson Comorbidity Index, and Nutric Score, the risk of death increased by 1.27, 1.18, and 1.40 times, respectively. Intravenous immunoglobulin, administered to a select group of patients, reduced the risk of death by 23.8 times. The optimal threshold value for CLR was identified as 103.05, with values above this increasing the risk of death by 1.84 times. Critically ill patients with CLR values exceeding the identified threshold should receive more intensive monitoring and timely adjustments in treatment. Given that CLR is a simple, accessible, and cost-effective marker, it holds particular value in managing aggressive diseases like COVID-19.