The risk of Parkinson’s disease in inflammatory bowel disease: A systematic review and meta-analysis

Abstract Background Several studies have reported an increased prevalence of Parkinson disease (PD) amongst patients with inflammatory bowel disease (IBD) with conflicting results. We aimed to evaluate the risk of PD in the IBD population by conducting a meta-analysis (MA). Methods A systematic review with MA of the existing literature was conducted. The main outcome of interest was the incidence of developing PD in patients previously diagnosed with IBD. Results Four studies were included in this MA. The overall risk of PD in IBD was significantly higher than controls (RR 1.41, 95% c.i. 1.19–1.66). Crohn’s disease had a 28% increased risk of PD and ulcerative colitis had a 30% increased risk of PD compared to controls (CD: RR 1.28, 95% c.i. 1.08–1.52, UC: RR 1.30, 95% c.i. 1.15–1.47). Conclusion The MA detected an increased risk of PD in the IBD population and CD/UC subgroup. These results merit further clinical validation in future studies.