Association between irritable bowel syndrome and Parkinson's disease: A systematic review and meta-analysis

Background Growing evidence suggests that irritable bowel syndrome (IBS) and Parkinson's disease (PD) share similar pathological mechanisms and risk factors. Methods We performed a systematic review and meta-analysis of the evidence for a relationship between IBS and PD. Risk estimates from individual studies were pooled using random-effects models. Results Six articles involving 58,645 patients with PD were included in our meta-analysis. The overall risk for PD in IBS patients was significantly higher than that in the general population (odds ratio [OR], 1.5; 95% confidence interval [CI], 1.29-1.75; p < .001). Subgroup analysis revealed no significant differences in risk between men (OR = 1.47, 95% CI: 1.3-1.67; p < .001) and women (OR = 1.51, 95% CI: 1.29-1.75; p < .001); however, older (>= 65 years) IBS patients (OR = 1.44, 95% CI: 1.3-1.59; p < .001) may be at higher risk for PD than younger (40-64 years) patients (OR = 1.32, 95% CI: 1.05-1.64; p = .017). Conclusion Overall, the PD risk was higher in IBS patients than others, indicating that the intestinal disorder may serve as a warning sign for PD.