Inflammatory bowel disease and bipolar disorder: A population-based cross-sectional study

Background: To date, some experimental studies showed that inflammatory bowel disease (IBD) and bipolar disorder (BD) may share similar biological pathways. Nevertheless, only a few western studies have attempted to demonstrate the potential association between IBD and BD, and relevant findings are still conflicting. Therefore, this cross-sectional study aimed to evaluate the relationship between IBD and BD using a nationwide database in Taiwan. Method: This study used data from the National Health Insurance Research Database. In total, 3590 patients with IBD and 14,360 propensity score-matched comparison patients without IBD were included in this study. Conditional logistic regressions were performed to evaluate the association between BD and IBD. Results: Results showed that BD was found in 26 (0.72%) patients with IBD and in 49 (0.34%) matched comparison patients without IBD. After adjustment, the adjusted odds ratio (OR) of BD for IBD patients was 2.10 (95% confidence interval (CI): 1.30∼3.38) compared to the comparison group. Additionally, this study showed that adjusted OR of BD for ulcerative colitis patients were 2.23 (95% CI: 1.31∼3.82) compared to the comparison group. Limitations: we could not precisely determine the causal association between BD and IBD. Conclusions: We concluded that patients with IBD were more likely to have BD than those comparison patients without IBD.