Investigating the Effect of High-Dose Vitamin D3 Administration on Inflammatory Biomarkers in Patients with Moderate to Severe Traumatic Brain Injury: A Randomized Clinical Trial

Background: Traumatic brain injury (TBI) is one of the most common neurological disorders worldwide. We aimed to investigate the efficacy of high-dose vitamin D3 on inflammatory biomarkers in patients with moderate to severe TBI. Methods: Thirty-five moderate to severe TBI patients were randomly assigned to intervention and control groups. Patients in the intervention group received a single intramuscular (IM) dose of 300,000 IU vitamin D. The primary endpoints were interleukin levels (IL-1β and IL-6), and the secondary endpoints were changes in neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), Glasgow Coma scale (GCS), and Glasgow Outcome Scale-Extended (GOS-E) scores compared between intervention and control arms of the study. The linear Generalized Estimating Equations were used for trend analysis and evaluating the association of independent factors to each outcome.Results: The results revealed a significant decrease in IL-1β levels (-2.71±3.02, in the intervention group: P=0.001 vs. -0.14±3.70, in the control group: P=0.876) and IL-6 (-88.05±148.45, in the intervention group: P=0.0001 vs. -35.54±175.79, in the control group: P=0.325) 3 days after the intervention. The improvement in the GCS score (P=0.001), reduction in NLR (P=0.001) and PLR (P=0.002), and improvement in the GOS-E score (P=0.039) was found to be greater in the vitamin D3 arm of the study than the control group.Conclusion: Administration of high-dose vitamin D3 in the acute phase of TBI could be effective in lowering the inflammatory markers and improving the level of consciousness and long-term performance outcomes.Trial registration number: IRCT20180522039777N2.