Comparison of Hematological Parameters Between Survivors and Non-Survivors COVID-19 Patients in Saudi Arabia

Coronavirus disease 2019, caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), is a communicable disease transmitted through the respiratory route and bodily contact. The severity of infection and mortality rate of COVID-19 cases was significantly high in the initial stages of the pandemic. This study aims to investigate the hematological profile of COVID-19 survivors and non-survivors.

This is a single-center retrospective study. A total of 108 hospitalized patients with laboratory-confirmed COVID-19 at East Jeddah Hospital between April and August 2020 were categorized into two groups based on outcome as survivors (n = 54) and non-survivors (n = 54). Hematological parameters and clinical profiles were analyzed and compared between the two groups.

The mean age and standard deviation of the survived (30-71 years) and non-survived (33-83) groups was 53 ± 10.8 and 57.9 ± 12.2 years, respectively, with no statistically significant difference in age between groups (p = 0.0513). Non-survivors had a significantly longer median length of stay in the intensive care unit (ICU) (7 days, IQR: 4.24 to 12) compared to survivors COVID-19 patients (5 days, IQR: 0 to 11.75) (p = 0.0151). For the survivors group, the participant's age positively correlated with the length of hospital stay (r(52) = 0.21, p = 0.0005) and ICU length of stay r(52) = 0.18, p = 0.001). The median red blood cells (RBC) counts were significantly higher in the survived group (4.56x10⁹/L, IQR: 4.02 to 5.11) in comparison with the non-survived (4.23x10⁹/L, IQR: 3.75 to 4.23) group (p = 0.0011). All COVID-19 patients exhibited lymphocytopenia and a significant negative correlation was observed between the lymphocyte values and length of hospital stay among the survived group (p < 0.001) as well as length of ICU stay among the survived group (p < 0.0480). Disease-related mortality was significantly associated with reduced white blood cells (WBCs) (8.5×10⁹/L, IQR: 6.1 to 11.7) and reduced basophils (0.09%, IQR: 0.02 to 0.19). Additionally, statistically significant differences were found between the survived and non-survived groups with respect to prothrombin time (PT) (12.5 sec. vs 14 sec., p < 0.0001) and partial thromboplastin time (PTT) (31.8 sec. vs 40 sec., p = 0.0008).

Hematological parameters can serve as valuable indicators to identify patients with severe COVID-19 and expected poor-prognosis/outcomes upon hospital admission. Cell counts of lymphocytes, WBCs, basophils and parameters such as PT and PTT can serve as clinical indicators to assess disease severity and predict progression to critical illness.