The Association of Hemoglobin and Body Mass Index and the Outcomes of COVID-19: A Prospective Cohort Study

Background: Previous studies indicated the risk factors for COVID-19. It is known that nutritional status is one of the main causes of immune system failure. This study aims to investigate the association of nutritional status and the outcomes of COVID-19 in participants of Yazd Health Study (YaHS). Methods: 279 people who had taken a blood test before contracting COVID-19 were included in this study in 2022. Data of PO2 level, rate of hospitalization, "supplementation with oxygen" rate, BUN, and creatinine were extracted. Hemoglobin levels and body mass index (BMI) were also evaluated. The authors applied analysis of variance (ANOVA) and independent sample t-test to show differences between levels of BMI and hemoglobin. All statistical analyses were conducted using IBM SPSS version 22.0 software. Results: The results showed a significant difference between hemoglobin levels and different BMI levels (P = 0.03). However, there was no significant relationship between different BMI levels and BUN (P = 0.34), creatinine (P = 0.42), BUN/Cr (P = 0.14), PO2 (P = 0.34), supplementation with oxygen (P = 0.26), and hospitalization rates (P = 0.97). The results according to the normal and abnormal hemoglobin levels were not significant. Conclusion: According to the criteria used in this study to assess nutritional status (BMI and hemoglobin levels), there was no significant relationship between nutritional status (different levels of BMI and hemoglobin) and COVID-19 outcomes, including hospitalization rate, “supplementation with oxygen” rate, and low PO2 levels. Further studies in different countries using other nutritional status assessment tools are needed to confirm these findings.