Different Classes of Antibiotics, by Provoking Distinct Patterns of Dysbiosis, May Affect the Occurrence of Inflammatory Bowel Disease

The predominant forms of inflammatory bowel disease (IBD) are Crohn's disease and ulcerative colitis, which occur in approximately 0.5-1% of the World population. Alterations in the microbial flora (dysbiosis) are considered the primary precipitating factor in IBD. Because antibiotics are major disruptors of the microbiome, it was hypothesized that different antibiotic classes might induce distinct alterations in gut flora, reflected in positive or negative associations with IBD incidence at the population level. Average yearly consumption was calculated from ECDC reports (2004-2023) for the major antibiotic classes, which cover 99.87% of total antibiotic consumption across 30 European countries. Data were compared with age-stratified IBD incidence (15–39 years) estimated for 2021. Ordinal logistic regression modeled the association between antibiotic class proportions and IBD-incidence categories, entering each antibiotic class separately as a continuous predictor. Pearson correlation analyses were conducted to assess linear associations, and Kruskal-Wallis tests were applied to compare incidence categories. Statistical significance was set at p < 0.05. Tetracyclines (J01A), narrow-spectrum penicillin (J01CE, J01CF), and sulfonamides (J01E) showed a significant positive association with IBD incidence, indicating that higher consumption was associated with higher national incidence. In contrast, cephalosporins, macrolides, aminoglycosides, and quinolones showed significant negative associations, suggesting links to lower national incidence levels. Different antibiotic consumption patterns across 30 European countries may be associated with the IBD incidence.