Bolus weekly vitamin D3 supplementation impacts gut and airway microbiota in adults with cystic fibrosis: a double-blind, randomized, placebo-controlled clinical trial.
Study design (if review, criteria of inclusion for studies)
RCT
Participants
Adults with CF and vitamin D insufficiency (25(OH)D <30 ng/mL). Two groups - vitamin D insufficient (n=23) and vitamin D sufficient (n=18).
Interventions
Subjects with vitamin D insufficiency were randomized to receive 50,000 IU of oral vitamin D3 or placebo weekly for 12 weeks.
Outcome measures
Sputum and stool samples were obtained pre and post intervention and 16S rRNA genes sequenced using Illumina MiSeq technology.
Main results
Gut microbiota differed significantly based on vitamin D status with Gammaproteobacteria, which contain numerous potentially pathogenic species, being enriched in the vitamin D insufficient group. PCoA analysis showed differential gut microbiota composition within the vitamin D insufficient patients following 12 weeks treatment with placebo or vitamin D3 (Permanova = 0.024) with Lactococcus significantly enriched in subjects treated with vitamin D3, whereas Vellionella and Erysipelotrichacea were significantly enriched in patients treated with placebo.
Authors' conclusions
This exploratory study suggests vitamin D insufficiency is associated with alterations in microbiota composition that may promote inflammation and that supplementation with vitamin D has the potential to impact microbiota composition. Additional studies to determine vitamin D's impact on the microbiota benefits clinical outcomes in CF are warranted.