COVID-19 is more dangerous for older people and its severity is increasing: a case-control study

Coronavirus disease 2019 (COVID-19) triggers important changes in routine blood tests. In this retrospective case-control study, biochemical, hematological and inflammatory biomarkers between March 10, 2020, and November 30, 2020 from 3969 COVID-19 patients (3746 in the non-intensive care unit (non-ICU) group and 223 in the ICU group) were analyzed by dividing into three groups as spring, summer and autumn. In the non-ICU group, lymphocyte to monocyte ratio was lower in autumn than the other two seasons and neutrophil to lymphocyte ratio was higher in autumn than the other two seasons. Also, monocyte and platelet were higher in spring than autumn; and eosinophil, hematocrit, hemoglobin, lymphocyte, and red blood cells decreased from spring to autumn. In the non-ICU group, alanine aminotransferase and gamma-glutamyltransferase gradually increased from spring to autumn, while albumin, alkaline phosphatase, calcium, total bilirubin and total protein gradually decreased. Additionally, C-reactive protein was higher in autumn than the other seasons, erythrocyte sedimentation rate was higher in autumn than summer. The changes in routine blood biomarkers in COVID-19 varied from the emergence of the disease until now. Also, the timely changes of blood biomarkers were mostly more negative, indicating that the disease progresses severely. The study was approved by the Erzincan Binali Yildirim University Non-interventional Clinical Trials Ethic Committee (approval No. 86041) on June 21, 2021.

How do routine laboratory tests change in coronavirus disease 2019?

How the routine laboratory tests change in terms of coronavirus disease 2019 (COVID-19) was retrospectively analyzed in a large group of patients. Biochemical, hematological and inflammatory variables of a totaly 555 (n = 532 in non-intensive care unit (non-ICU), n = 23 in ICU) patients diagnosed with COVID-19 were analyzed accessing them through the laboratory information system. White blood cell (WBC), neutrophil (NEU), platelet large cell ratio, neutrophil to lymphocyte ratio (NLR), derived NLR (d-NLR), aspartate aminotransferase, urea, creatine kinase (CK) myocardial band (CK-MB), procalcitonin (PCT) values were high whereas lymphocyte (LYM), eosinophil, red blood cells (RBC), hemoglobin, lymphocyte to monocyte ratio, estimated glomerular filtration rate values were low in the ICU group when compared with non-ICU. WBC, NEU, red cell distribution width, alanine transaminase, creatinine, urea, CK-MB, CK, direct bilirubin, lactate dehydrogenase, glucose, C-reactive protein, erythrocyte sedimentation rate, ferritin, D-dimer, PCT and international normalized ratio values increased while RBC, hemoglobin, hematocrit, mean corpuscular volume and total bilirubin values decreased in a significant proportion of patients in both groups based on the normal reference ranges. LYM count was found to be low in a significant number of patients (57.5%) especially in the ICU group and as an important risk factor and diagnostic parameter on admission to ICU (OR: 125, AUC: 0.74). Routine laboratory tests provide important information in terms of both diagnosis and severity of COVID-19. Lymphopenia is a condition that should be monitored which indicates the severity of the disease.