Efficacy of High-Dose Vitamin D Supplementation as an Adjuvant Treatment on Pneumonia: Systematic Review and a Meta-Analysis of Randomized Controlled Studies.

The purpose of this meta-analysis was to summarize randomized controlled trial (RCT) evidence and evaluate the efficacy and safety of vitamin D (VD) supplementation as an adjunct to antibiotics for the treatment of pneumonia. Data sources published from the inception dates up to January 2020 were searched. RCTs of VD supplementation of any duration, age, and dosing regimen type were eligible for inclusion if data on pneumonia were collected. Thirteen studies (4786 randomized participants) fulfilled eligibility criteria. VD supplementation significantly increased levels of serum 25(OH)D (mean difference = 15.97; 95% CI, 7.49-24.44; P = .002) and reduced incidence of repeat episodes of pneumonia (risk ratio [RR] = 0.68; 95% CI, 0.50-0.93; P = .02). Subgroup analysis revealed VD supplementation had more reducing effects on repeat episodes of pneumonia among participants in trials in which the population were children (RR = 0.66; 95% CI, 0.48-0.90), duration <3 months (RR = 0.55; 95% CI, 0.33-0.91), or dose of VD <300,000 IU (RR = 0.51; 95% CI, 0.29-0.89). Although our results suggested that VD supplementation had a positive effect on recovery rate of pneumonia (RR = 1.28; 95% CI, 0.94-1.74; I2 = 13%), there was no statistical difference (P = .12). High-dose VD intervention may have an effect on reducing the incidence rate of repeat episodes of pneumonia by enhancing immune efficacy, although more population studies are needed to support that VD supplementation has therapeutic effects on pneumonia itself.