Effects of a 2-Week 5000 IU versus 1000 IU Vitamin D3 Supplementation on Recovery of Symptoms in Patients with Mild to Moderate Covid-19: A Randomized Clinical Trial.

Shaun Sabico, Mushira A Enani, Eman Sheshah, Naji J Aljohani, Dara A Aldisi, Naif H Alotaibi, Naemah Alshingetti, Suliman Y Alomar, Abdullah M Alnaami, Osama E Amer, Syed D Hussain, Nasser M Al-Daghri

Journal: Nutrients 2021;13(7):2170

PMID: 34202578

Plain Language Summary

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A highly contagious virus called SARS-CoV-2 is responsible for the Covid-19 pandemic. Vitamin D adjuvant therapy has been identified as a promising strategy for reducing the severity of Covid-19 outcomes in the elderly. Also, a low Vitamin D status significantly correlates with Covid-19 severity. This multi-centre randomised, open-label clinical trial evaluated the beneficial effects of 5000 IU versus 1000 IU Vitamin D3 daily supplementation for two weeks on recovery of symptoms in patients with mild-to-moderate Covid-19 and suboptimal Vitamin D status. Thirty-six Covid-19 patients received 5000 IU Vitamin D3 daily, and thirty-three Covid-19 patients received 1000 IU Vitamin D3 daily. The 5000 IU Vitamin D3 group was significantly younger and had a significantly lower BMI than the 1000 IU Vitamin D3 group. The 5000 IU Vitamin D3 group showed significant improvements in the severity of the Covid-19 symptoms compared to the 1000 IU Vitamin D3 group. Further robust studies are needed to evaluate the effects of Vitamin D3 supplementation in patients with high BMI, severe Covid-19 symptoms, and prevention of Covid-19. Healthcare professionals can use the results of this study to understand the effects of different doses of Vitamin D3 supplements in patients with mild-to-moderate Covid-19 symptoms and suboptimal Vitamin D status.

Abstract

OBJECTIVE

Vitamin D deficiency has been associated with an increased risk of COVID-19 severity. This multi-center randomized clinical trial aims to determine the effects of 5000 IU versus 1000 IU daily oral vitamin D3 supplementation in the recovery of symptoms and other clinical parameters among mild to moderate COVID-19 patients with sub-optimal vitamin D status.

STUDY DESIGN AND SETTING

A total of 69 reverse transcriptase polymerase chain reaction (RT-PCR) SARS-CoV-2 positive adults who were hospitalized for mild to moderate COVID-19 disease were allocated to receive once daily for 2 weeks either 5000 IU oral vitamin D3 ( = 36, 21 males; 15 females) or 1000 IU oral vitamin D3 (standard control) ( = 33, 13 males; 20 females). Anthropometrics were measured and blood samples were taken pre- and post-supplementation. Fasting blood glucose, lipids, serum 25(OH)D, and inflammatory markers were measured. COVID-19 symptoms were noted on admission and monitored until full recovery.

RESULTS

Vitamin D supplementation for 2 weeks caused a significant increase in serum 25(OH)D levels in the 5000 IU group only (adjusted = 0.003). Within-group comparisons also showed a significant decrease in BMI and IL-6 levels overtime in both groups (-values < 0.05) but was not clinically significant in between-group comparisons. Kaplan-Meier survival analysis revealed that the 5000 IU group had a significantly shorter time to recovery (days) than the 1000 IU group in resolving cough, even after adjusting for age, sex, baseline BMI, and D-dimer (6.2 ± 0.8 versus 9.1 ± 0.8; = 0.039), and ageusia (loss of taste) (11.4 ± 1.0 versus 16.9 ± 1.7; = 0.035).

CONCLUSION

A 5000 IU daily oral vitamin D3 supplementation for 2 weeks reduces the time to recovery for cough and gustatory sensory loss among patients with sub-optimal vitamin D status and mild to moderate COVID-19 symptoms. The use of 5000 IU vitamin D3 as an adjuvant therapy for COVID-19 patients with suboptimal vitamin D status, even for a short duration, is recommended.

Address: Chair for Biomarkers of Chronic Diseases, Biochemistry Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.; Infectious Diseases Section, King Fahad Medical City, Riyadh 59046, Saudi Arabia.; Diabetes Care Center, King Salman Bin Abdulaziz Hospital, Riyadh 12769, Saudi Arabia.; Chair for Biomarkers of Chronic Diseases, Biochemistry Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.; Obesity, Endocrine and Metabolism Center, Department of Medicine, King Fahad Medical City, Riyadh 59046, Saudi Arabia.; Department of Community Health Sciences, College of Applied Medical Sciences, King Saud University, Riyadh 11451, Saudi Arabia.; Department of Medicine, College of Medicine, King Saud University, Riyadh 12372, Saudi Arabia.; Obstetrics and Gynaecology Department, King Salman Bin Abdulaziz Hospital, Riyadh 11564, Saudi Arabia.; Doping Research Chair, Department of Zoology, College of Science, King Saud University, Riyadh 11495, Saudi Arabia.
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