Study design (if review, criteria of inclusion for studies)
Trials using both single and combined fibreâprebiotic interventions of inulin, FOS and GOS. Authors will exclude candidate fibre prebiotics of resistant starch, polydextrose, xyloâoligosaccharide, imaltoâoligosaccharide and isomaltoâoligosaccharide due to the lack of evidence to accepted them as qualified prebiotics; candidate nonâfibre prebiotics polyphenolics, and polyunsaturated fatty acids. We will exclude in vitro trials or trials examining the effect of probiotics alone or synbiotics (without adequate description on dose of prebiotic and type of prebiotic used).
Children and adults with CF, who fulfil consensus diagnostic criteria for CF (Farrell 2017). No restrictions for participants in terms of age, gender, genotype, pancreatic exocrine sufficiency status, disease severity, comorbidities, antibiotic use or CFTR modulator therapy.
Prebiotics, defined as "a substrate that is selectively utilised by host microorganisms conferring a health benefit". Authors will compare any oral fibreâprebiotic (inulin, FOS and GOS, dose or formulation, without a probiotic) to any other prebiotic formulation, probiotic or synbiotic, or placebo or no control treatment. Soluble fibreâprebiotic inulin, fructoâoligosaccharides (FOS), and galactoâoligosaccharides (GOS) and human milk oligosaccharides (HMOs).
Primary outcomes: 1) Growth and nutrition (mean change from baseline and postâtreatment absolute mean): height, weight, BMI. 2) GI symptoms measured using the multimodal questionnaire for the assessment of abdominal symptoms in people with cystic fibrosis (CFAbd Score). 3) Adverse events. Secondary outcomes. Secondary outcomes: pulmonary exacerbations, lung function (mean change from baseline and postâtreatment absolute mean), inflammatory biomarkers, hospitalisations (all causes), Healthârelated quality of life (HRQoL) measured using a validated questionnaire (e.g. Cystic Fibrosis Questionnaire â Revised (CFQâR); Quittner 2009).