The effect of lymphocyte blood levels on mortality of COVID-19 patients under intensive care unit follow-up.

Objective: Lymphocytes are the most important cells in defending the human body against viral pathogens. In this study, we aimed at investigating the relationship between lymphocyte blood levels and patient survival in COVID-19 patients hospitalized in the intensive care unit.

Patients And Methods: We retrospectively evaluated patients hospitalized with COVID-19 pneumonia in the intensive care unit. Patients were divided into two groups in terms of blood lymphocyte levels; increased lymphocyte and decreased lymphocyte groups on the 5th day of hospitalization. Mortality rates were compared between groups.

Results: Two groups were similar in terms of laboratory tests and comorbidities. Overall survival was 63.8% (n=102) in patients with increased lymphocytes and 33.2% (n=68) in patients with decreased lymphocytes. Mortality rates were significantly higher in decreased lymphocyte group than in increased lymphocyte group (p=0.003).

Conclusions: Our study reveals that mortality is higher in patients with a lower lymphocyte count on the 5th day compared to the day of hospitalization.