• Amol Singhsakul Department of Internal Medicine, Banphaeo General Hospital
  • Bancha Satirapoj Division of Nephrology, Phramongkutklao Hospital
  • Sirinthip Nimitphuwadon Research Center, Banphaeo General Hospital
  • Sirate Rapeepattana Research Center, Banphaeo General Hospital
  • Saovanee Benjamanukul Department of Internal Medicine, Banphaeo General Hospital
  • Sasiwimon Traiyan Department of Pediatric, Allergy and Asthma Unit, Banphaeo General Hospital



COVID-19, vitamin D deficiency, vitamin D insufficiency, COVID-19 severity


Background: Studies indicate that vitamin D can lower the incidence of viral respiratory infections and is necessary for the human immune system to function properly. Vitamin D deficiency may be a risk factor for the severity of COVID-19, including mortality, hospitalization, and length of hospital stay.

Objectives: This study aimed to investigate the association between vitamin D levels and the severity of COVID-19 disease.

Methods: The participants were COVID-19 patients aged 18 years or older who tested positive for the virus on Real-Time PCR tests, treated as inpatients at Banphaeo General Hospital between September 1 and November 30, 2021. For each patient, baseline characteristics, including sex, weight, height, and underlying diseases, were collected. Three categories were used to categorize COVID-19 disease: mild, moderate, and severe. At the beginning of the study, blood tests were performed on each patient to determine their 25-hydroxyvitamin D levels.

Results: Of 97 patients, 64 were male (66%), with a mean age of 50.8±17.7 years. The mean vitamin D level was 27.8±9.6 ng/mL, with 45 (46.4%) showing vitamin D deficiency and 39 (40.2%) indicating vitamin D insufficiency. Among COVID-19 patients with vitamin D deficiency, 28 (63.6%) were classified as severe, compared to only 16 severe cases (36.4%) among those without vitamin D deficiency, demonstrating statistically significant differences (p=0.006). Patients with vitamin D deficiency had a 3.97 times higher risk of experiencing severity (95% CI: 1.67, 9.41, p=0.002) than those without a vitamin D deficit. After adjusting for variable factors, results indicated that patients with vitamin D deficiency had a 3.78-fold increased risk of getting severe illness than those without deficiency (95% CI: 1.28, 11.19, p=0.016). Conclusion: These findings suggested that vitamin D deficiency was associated with the severity of COVID-19.


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How to Cite

Singhsakul A, Satirapoj B, Nimitphuwadon S, Rapeepattana S, Benjamanukul S, Traiyan S. ASSOCIATION OF VITAMIN D LEVEL AND SEVERITY OF COVID-19 DISEASE. J Southeast Asian Med Res [Internet]. 2024 Jun. 9 [cited 2024 Jun. 16];8:e0202. Available from:



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