Effect of Vitamin D Supplementation on Post-COVID-19 Manifestations in Menoufia University Hospitals: A Randomized Controlled Clinical Trial

Background: The aftermath of the COVID-19 pandemic has given rise to a diverse array of challenges impacting multiple facets of daily life. Vitamin-D, renowned for its immunomodulatory properties, has been implicated in mitigating viral infections, preventing complications, and arresting the progression of chronic conditions. Objectives: To evaluate the effect of vitamin-D supplementation in ameliorating post-COVID-19 symptoms. Methods: A randomized-controlled-clinical-trial was conducted on 111 post-COVID-19 patients recruited from the post-COVID-19 Outpatient Clinic at Menoufia University Hospital between October 2021 and June 2022. Before the intervention, baseline data, detailed medical history, and clinical assessments were collected. Additionally, serum vitamin-D levels were measured in all patients. Subsequently, participants were randomly assigned to a 2-month supplementation regimen, either the vitamin-D group, receiving a daily oral dose of vitamin-D (2000 IU/tablet), or a visually identical placebo. Results: Among patients with insufficient vitamin-D levels, approximately 75.7% experienced more than 3 post-COVID-19 symptoms. A notable negative correlation was observed between the frequency of post-COVID-19 symptoms and vitamin-D levels (R=-0.505, P-value< 0.001). After a 2-month intervention with vitamin-D, compared to the placebo, there was a significant improvement in various symptoms such as fatigue, sleep disturbance, lack of concentration, cough, myalgia, arthralgia, and hair loss (P-value<0.001). Conclusion: This study establishes a significant connection between vitamin-D deficiency and persistent post-COVID-19 symptoms, emphasizing the beneficial role of vitamin-D in relieving symptoms. The findings support the routine assessment of vitamin-D levels in individuals with post-COVID-19 symptoms, with a recommendation for vitamin-D supplementation in cases of deficiency.