Abstract
Individuals with cystic fibrosis (CF) have dysfunctional intestinal microbiota and increased gastrointestinal (GI) inflammation also known as GI dysbiosis. It is hypothesized that administration of high-dose cholecalciferol (vitamin D(3)) together with a prebiotic (inulin) will be effective, and possibly additive or synergistic, in reducing CF-related GI and airway dysbiosis. Thus, a 2 x 2 factorial design, placebo-controlled, double-blinded, pilot and feasibility, clinical trial was proposed to test this hypothesis. Forty adult participants with CF were block-randomized into one of four groups: 1) high-dose oral vitamin D(3) (50,000 IU weekly) plus oral prebiotic placebo daily; 2) oral prebiotic (12 g inulin daily) plus oral placebo vitamin D(3) weekly; 3) combined oral vitamin D(3) weekly and oral prebiotic inulin daily; and 4) oral vitamin D(3) placebo weekly and oral prebiotic placebo. The primary endpoints included 12-week changes in the microbial bacterial communities, gut and airway microbiota richness and diversity before and after the intervention. This pilot study examined whether vitamin D(3) with or without prebiotics supplementation was feasible, changed airway and gut microbiota, and reduced dysbiosis, which in turn, may improve health outcomes and quality of life of patients with CF.