DESIGN: International, prospective, non-interventional registry of the clinical practice of the European gastroenterologists. Data were collected and quality reviewed until March 2021 at AEG-REDCap. The effectiveness was evaluated by modified intention-to-treat analysis, differentiating by geographic areas. Adverse events (AE) were categorized as mild, moderate, and severe.

RESULTS: Overall, 36,699 treatments were recorded, where 8,233 (22%) were prescribed with probiotics. Probiotics use was associated with higher effectiveness in the overall analysis (OR 1.631 [95% CI 1.456-1.828]), as well as in triple (1.702 [1.403-2.065]), quadruple (1.383 [0.996-1.920]), bismuth quadruple (1.248 [1.003-1.554] and sequential therapies (3.690 [2.686-5.069]). Lactobacillus genus was associated with a higher therapy effectiveness in Eastern Europe when triple (OR: 2.625 [CI 1.911, 3.606]) and bismuth quadruple (OR: 1.587 [CI 1.117, 2.254]) first-line therapies were prescribed. In Central Europe, the use of probiotics was associated with a decrease in both the overall incidence of AEs (0.656 [0.516, 0.888]) as well as severe AEs (0.312; [0.217, 0.449]). Bifidobacterium genus was associated with lower overall (OR: 0.725 [95% CI 0.592-0.888]) and severe (OR: 0.254 [0.185-0.347]) AEs; and Saccharomyces was associated with reduced overall (OR: 0.54 [CI 0.32-0.91]) and severe (OR 0.257 [CI 0.123-0.536]) AEs under quadruple-bismuth regimen.