Probiotic use in adults with cystic fibrosis is common and influenced by gastrointestinal health needs: A cross-sectional survey study

Background: Cystic fibrosis (CF) primarily affects the lung, however, gastrointestinal disorders and symptoms, including dysbiosis, also impact on morbidity and quality of life. There is interest in strategies to modulate the gastrointestinal microbiota, including probiotics, although the evidence remains inadequate to guide practice, and information on use is limited. The present study aimed to characterise probiotic use, beliefs and experiences of adults with CF. Methods: A cross-sectional questionnaire study was conducted in adults with CF (n = 205) and a general population Control group (n = 158), recruited from Victoria, Australia. Participants were classified as probiotic ‘Ever Users’ or ‘Never Users’. Outcomes included self-reported probiotic use and factors associated with probiotic use, which were analysed using logistic regression analysis. Open-ended questionnaire responses were thematically analysed. Results: In total, 70% of adults with CF had ever used probiotics (supplements and/or foods), comparable to Controls (80%) (p = 0.03). Key reasons for CF probiotic use were gastrointestinal- and antibiotic-related (75%). Most CF Ever Users (73%) did not discuss probiotic use with CF clinicians and 33% were uncertain if probiotics had been helpful. Female gender (odds ratio [OR] = 2.82; 95% confidence interval [CI] = 1.36–5.87; p = 0.005), university-level education (OR = 2.73; 95% CI = 1.24–6.01; p = 0.01) and bloating on antibiotics (OR = 2.14; 95% CI = 1.04–4.40; p = 0.04) were independently associated with probiotic use in CF; as was female gender in Controls (OR = 2.84; 95% CI = 1.20–6.71; p = 0.02). Conclusions: Probiotics were used by adults with CF for gastrointestinal- and antibiotic-related reasons often without informing clinicians and despite uncertainty about perceived helpfulness. Further research investigating gastrointestinal outcomes of probiotics will inform practice recommendations guiding their use in CF and other chronic diseases.