Document Type : Research articles


1 Bachelor of Laboratory Science, Arak university of medical science, Arak, Iran

2 Department of biology, Faculty of basic science, Shahrekord university, Iran

3 Professor of Biochemistry, Department of Biochemistry, School of Medicine, Arak University of Medical Sciences, Iran

4 Department of biostatistics and epidemiology, School of health, Isfahan university of medical science, Isfahan, Iran

5 Radiology Resident, Department of Radiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran


Background: Coronavirus disease 2019 (COVID-19), a severe disease caused by severe acute respiratory syndrome coronavirus 2, has a weak prognosis, and biological markers may predict disease severity.
Objectives: The present study aimed to assess the impact of vitamin D levels on COVID-19 outcomes in diabetic people.
Methods: The study was conducted on 160 individuals with both COVID-19 and diabetes at Amir-Al-Momenin Hospital in Arak. Participants completed a questionnaire regarding their personal information, medical history, and medication use. Arterial and venous blood samples were collected after 12 hours of fasting to perform arterial blood gas (ABG) and brachial venous fasting blood glucose tests, respectively. The samples were sent to the laboratory for analysis. Serum levels of 25-hydroxyvitamin D were measured using the ELISA method. The study groups were classified based on the obtained PO2 levels from the ABG test, indicating varying degrees of respiratory impairment.
Results: Patients were categorized as mild, moderate, or severe based on ABG test results. No significant difference was found in vitamin D levels among groups. Elevated levels of vitamin D in women and men with mild and moderate COVID-19 symptoms have been linked to a decrease in mortality rate. Nonetheless, significant correlations were observed between vitamin D and fasting blood sugar (FBS) levels in the mild and moderate groups, indicating varying relationships between vitamin D and FBS across these groups.
Conclusion: While immunizations and antiviral drugs work well against COVID-19, taking extra measures, such as vitamin D supplementation, plays a vital role in disease management.


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