Association of nutritional related biochemical markers with COVID-19 infection: a case-control study

Abstract Introduction: Since its detection, COVID19 has led to a worldwide health crisis with multi-systemic complications, involving the respiratory, cardiovascular, etc., health issues. Identifying of possible risk factors is important in finding the disease at an early stage and may improve the survival of patients. This study was carried out to evaluate inflammatory, hematological and nutritional indicators in order to determine the risk of COVID19 infection. Material and methods From 2021 to 2023 in Maragheh, northwest of Iran, 234 COVID19 cases and 160 nonCOVID19 controls were studied in this case-control study. Recruits were selected from referrals to local hospitals and health care centers of Maragheh University of Medical Scinces. Laboratory methods were used to determine the levels of serum vitamin D, potassium, CRP, and the hematological indices. Standard statistical analysis were performed in SPSS version 21and p-value less than 0.05 was considered statistically significant. Results The gender distribution was almost the same in both groups (54% female and 52% p = 0.858). The median serum level of CRP was higher in COVID19 patients 60.5 (40.0–85.0) mg/L compared to the non-COVID19 group 37.5 (20.0–65.0) mg/L (p < 0.001). The creatinine level was lower in the COVID19 group than in the non-COVID19 group (p = 0.033). Additionally, the median of vitamin D was significantly lower in COVID19 group 33.0 (IQR: 22.045.0) ng/mL (p < 0.001). The significant protective effect of vitamin D, potassium, creatinine, and lymphocyte to CRP (Lym. CRP) ratio with COVID19 was observed, while positive association was detected among age, CRP, and neutrophil to lymphocyte (Neu. Lym) ratio and increased risk of COVID19. Conclusion In conclusion, a simple approach to possibly lower the risk of COVID19 could be assessment inflammatory (CRP and lymphocyte to neutrophil ratio) and nutritional biomarkers (serum vitamin D and potassium).