COVID-19 Morbidity in Healthcare Workers and Vitamin D Supplementation
Condition: COVID-19 Respiratory Infection
MeSH terms: COVID-19; Respiratory Tract Infections
Study type: Interventional
Phase: Phase 4

Summary: 
      [Aim] Purpose of the study: to analyze the effect of vitamin D supplementation in reducing
      COVID-19 morbidity and severity in healthcare workers.

      The study will involve a minimum of 120 medical staff. All participants in the study will
      assess twice for serum 25(OH)D level: baseline and after 3 months of Vitamin D
      supplementation. After the baseline examination, the subjects will be randomized into 2
      groups. In the first (No. 1), vitamin D therapy will initiate at a dosage of 50,000 IU on the
      first and second week, followed by a switch to a daily intake of 5,000 IU for 3 months. In
      the second group (No. 2), vitamin D therapy will prescribe for 3 months at a dosage of 2,000
      IU/day. After 3 months of vitamin D supplementation, all participants will undergo to repeat
      testing of serum 25(OH)D level with an assessment of the effectiveness of the therapy. Body
      mass index (BMI), height, weight, SARS-CoV-2 antibodies (IgG), 25-hydroxycalciferol (25(OH)D)
      and presence of acute viral infection futures, parameters assessed after treatment.
    

Detailed description: 
      The COVID-19 pandemic that swept the world in 2019 radically changed not only the social
      sphere of life, subordinating everything around to its influence, but also the healthcare
      sector. It affected both its practical and scientific sides, globally changing the approach
      to medicine. Numerous studies around the globe are being conducted on the prevention and
      treatment of this infection. A significant amount of them study the role of vitamin D in the
      pathogenesis of the disease. Cholecalciferol (Vitamin D) is a fat-soluble vitamin that is
      involved in maintaining the serum calcium-phosphorus gradient. Vitamin D supplementation
      significantly reduces the risk of osteoporosis, and also affects the regulation of immune
      responses by modulating innate and adaptive immune responses. It has been shown to inhibit
      the proliferation of T cells, namely the subsequent transformation of Th1 cells to Th2 cells.
      This effect on cell proliferation and differentiation contributes to a significant decrease
      in the level of proinflammatory cytokines, thereby reducing the severity of immune-mediated
      damage. It was these mechanisms that formed the basis of the theory about the ability of
      vitamin D to prevent the severe course of coronavirus infection and even prevent it. At the
      moment, the effect of vitamin D on reducing COVID-19 morbidity is not fully confirmed.

      Patients and Methods: Baseline characteristics will be recorded for all patients including
      medical history, height, weight, body mass index (BMI), antibodies to SARS-CoV-2 (IgG) and
      25(OH)D. Serum 25(OH)D level, IgG to SARS-CoV-2 will be repeated at 12-14 weeks. Also, we
      will check information about clinical manifestation of COVID -19 and CT results in cases
      positive Ab. The research format is a prospective controlled single-center study. The study
      was carried out based on the Federal State Budgetary Institution, V. A. Almazov Federal
      North-West Medical Research Centre, of the Ministry of Health of the Russian Federation,
      October 30, 2020, to August 31, 2021. During the study, medical care workers who are working
      in an infectious hospital and who taking vitamin D in a controlled manner, having previously
      signed informed consent, will be observed. The study will be involved minimum 120 medical
      staff, including women and men. All subjects will be divided into three groups according to
      the criterion of having a higher, secondary, or no medical education. All participants in the
      study will be assessed twice for the level of 25-hydroxyvitamin D [25(OH)D], IgG to
      SARS-CoV-2 in their blood: before the start of therapy with cholecalciferol and after 3
      months of Vitamin D administration. After the screening, the subjects will be randomized into
      2 groups. In the Group 1, vitamin D therapy will be initiated at a dosage of 50,000 IU on the
      first and seventh week, followed by a switch to a daily intake of 5,000 IU for 12 weeks. In
      the Group 2, vitamin D therapy will be prescribed for 12 weeks at a dosage of 2,000 IU. After
      3 months of taking vitamin D supplementation, all participants will undergo to repeat testing
      of the 25(OH)D level in the blood with an assessment of the effectiveness of the therapy. IgG
      titer and PCR results will be compared in two groups of participations taking different doses
      of vitamin D supplementation.
    

Intervention name(s): Vitamin D
Intervention type(s): Drug
Intervention description(s): Patients will be randomised to receive either high dose vitamin D (50,000 IU weekly) on the first and second week, followed by a switch to a daily intake of 5,000 IU for 3 months or low dose vitamin D (2,000 IU weekly) for 3 months.
Intervention MeSH terms: Vitamin D
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Parallel Assigment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: level of 25-hydroxyvitamin D; COVID-19 disease; Healthcare Workers