Impact of Vitamin D Therapy on the Progress COVID-19: Six Weeks Follow-Up Study of Vitamin D Deficient Elderly Diabetes Patients

BACKGROUND: Coronavirus disease-19 (COVID-19) is an ongoing pandemic causing considerable fatalities worldwide. Vitamin D modulates the immune response through effects on various cells, such as: macrophages, B and T lymphocytes, neutrophils, and dendritic cells. AIM: To explore whether supplementation of vitamin D, in the form of a single intramuscular cholecalciferol injection, to patients with diabetes, COVID-19, and low vitamin D levels could improve the prognosis of those patients. METHODS: This was a placebo-controlled randomized prospective study. The study has two arms as follows: the intervention arm (40 vitamin D deficient diabetes elderly patients that acquired SARS-CoV-2), compared to the control arm (16 elderly diabetes patients, with deficient vitamin D with SARS-CoV-2). Patients in the intervention arm were given vitamin D as a single intramuscular injection (200,000 IU); patients in the control arm were given placebo. The primary outcome was mortality within 6 weeks of the diagnosis of COVID-19. Clinical, laboratory, treatment, and outcome data were recorded after 6 weeks of follow-up. RESULTS: No significant difference in 6 weeks mortality was observed between patients who received vitamin D and patients who received placebo (17.5% vs 18.8%, p = 0.838). Age, presence of hypertension, and chronic obstructive pulmonary disease were independent predictors of mortality at 6 weeks. CONCLUSION: Vitamin D supplementation did not reduce the severity or mortality of COVID-19 at 6 weeks. Further large scale studies are required to explore the effect of vitamin D therapy on survival in patients with diabetes mellitus who acquire COVID-19.