Vitamin D₃supplementation in patients with frequent respiratory tract infections: a randomised and double-blind intervention study

Abstract

BackgroundLow serum levels of 25-hydroxyvitamin D3 are associated with an increased risk of respiratory tract infections (RTIs). Clinical trials with vitamin D3 against various infections have been carried out but data are so far not conclusive. Thus, there is a need for additional randomised controlled trials of effects of vitamin D3 on infections.ObjectiveTo investigate if supplementation with vitamin D3 could reduce infectious symptoms and antibiotic consumption among patients with antibody deficiency or frequent RTIs.DesignA double-blind randomised controlled trial.SettingKarolinska University Hospital, Huddinge.Participants140 patients with antibody deficiency (selective IgA subclass deficiency, IgG subclass deficiency, common variable immune disorder) and patients with increased susceptibility to RTIs (>4 bacterial RTIs/year) but without immunological diagnosis.InterventionVitamin D3 (4000 IU) or placebo was given daily for 1 year.Primary and secondary outcome measuresThe primary endpoint was an infectious score based on five parameters: symptoms from respiratory tract, ears and sinuses, malaise and antibiotic consumption. Secondary endpoints were serum levels of 25-hydroxyvitamin D3, microbiological findings and levels of antimicrobial peptides (LL-37, HNP1–3) in nasal fluid.ResultsThe overall infectious score was significantly reduced for patients allocated to the vitamin D group (202 points) compared with the placebo group (249 points; adjusted relative score 0.771, 95% CI 0.604 to 0.985, p=0.04).LimitationsA single study centre, small sample size and a selected group of patients. The sample size calculation was performed using p=0.02 as the significance level whereas the primary and secondary endpoints were analysed using the conventional p=0.05 as the significance level.ConclusionsSupplementation with vitamin D3 may reduce disease burden in patients with frequent RTIs.

Efficacy of vitamin D in children with pneumonia: a randomized control trial study

“…From this we can conclude that vitamin D supplementation in a high dose may not immediately help in recovery from pneumonia, but it can definitely prevent further episodes of new pneumonia. The findings were comparable with other studies done which showed similar results [12,17].…”

Efeitos da vitamina D na prevenção da bronquiolite viral aguda: revisão sistemática

“…The findings of the study by El-Mazary et al [19], in infants who lived in urban areas and with dark skin (factors that increase the incidence of vitamin D deficiency due to less exposure to sunlight), agree with a randomized double blind study performed in 2012, with adults who had immunodeficiency, which demonstrated that vitamin D intake reduced the risk of acute LRTI, frequent in the winter [20] R. In addition to these studies, there are other evidences such as a prospective cohort study conducted by Belderbos et al [21], which demonstrated that healthy newborns with vitamin D deficiency had an increased risk for LRTI, especially AVB caused by RSV in the first year of life. Recently, two systematic reviews demonstrated that vitamin D intake reduced significantly the risk of respiratory tract infections; however, these reviews did not assess the direct association between vitamin D and AVB [16,22].…”

Vitamin D supplementation guidelines

“…Vitamin D has shown a strong immunomodulatory capacity; high VDR levels have been reported in macrophages, dendritic cells, T lymphocytes, and B lymphocytes supports the conception of its fundamental role in combating bacteria, and preventing both autoimmune diseases and chronic inflammatory states (47)(48)(49)(50). The available evidence of extra-skeletal vitamin D actions and related health benefits is growing (5,7,9,.…”