Causal Linkage Between Inflammatory Bowel Disease and Primary Sclerosing Cholangitis: A Two-Sample Mendelian Randomization Analysis
Related Experiment Video
Updated: Nov 10, 2025
Chronic Salmonella Infection Induced Intestinal Fibrosis
Published on: September 22, 2019
Ying Xie1, Xuejie Chen2, Minzi Deng2
1Centre for Global Health, Zhejiang University School of Medicine, Hangzhou, China.
Insights
Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease, causally increases the risk of primary sclerosing cholangitis (PSC). These findings support targeted prevention and treatment strategies for IBD and PSC patients.
Area of Science:
- Genetics and Epidemiology
- Gastroenterology
- Hepatology
Background:
- Observational studies suggest a link between inflammatory bowel disease (IBD) and primary sclerosing cholangitis (PSC).
- The causal relationship between IBD (ulcerative colitis, Crohn's disease) and PSC remains uncertain.
- Primary sclerosing cholangitis is a chronic liver disease characterized by bile duct inflammation and obstruction.
Purpose of the Study:
- To investigate the potential causal association between IBD and PSC using a robust genetic approach.
- To differentiate between association and causation in the IBD-PSC relationship.
- To provide evidence-based insights for clinical management.
Main Methods:
- Two-sample Mendelian randomization (MR) analysis was employed.
- Single nucleotide polymorphisms (SNPs) from genome-wide association studies (GWASs) were utilized as instrumental variables.
- Pleiotropy, heterogeneity, and sensitivity analyses were conducted for rigorous quality control.
Main Results:
- Mendelian randomization analysis revealed a significant causal effect of IBD (including ulcerative colitis and Crohn's disease) on PSC.
- Robust Adjusted Profile Score (RAPS) analysis showed increased odds of PSC in individuals with IBD (OR = 1.29), UC (OR = 1.40), and CD (OR = 1.13).
- Statistical heterogeneity and sensitivity analyses confirmed the robustness of the findings, despite some SNP variability.
Conclusions:
- The study provides strong genetic evidence supporting a causal role of IBD in the development of PSC.
- Findings suggest that IBD may be a risk factor for PSC in European populations.
- The results have implications for the prevention and treatment strategies for both IBD and PSC.
Background:
Observational studies suggest an association between inflammatory bowel disease (IBD) [including ulcerative colitis (UC) and Crohn's disease (CD)] and Primary sclerosing cholangitis (PSC), but the causal association between the two diseases remains unclear.
Methods:
We used two-sample Mendelian randomization (MR) to estimate the causal association between IBD and PSC. We chose single nucleotide polymorphisms (SNPs) data for analysis, obtained from previous genome-wide association studies (GWASs). Pleiotropy, heterogeneity, and sensitivity analyses were performed for quality control.
Results:
We found that the causal associations between IBD (both UC and CD) and PSC were significant (e.g., IBD and PSC, Robust adjusted profile score (RAPS) OR = 1.29, 95% CI 1.16∼1.44, p< 0.01; UC and PSC, RAPS OR = 1.40, 95% CI 1.23∼1.58, p< 0.01; CD and PSC, RAPS OR = 1.13, 95% CI 1.02∼1.26, p = 0.02). MR Egger, IVW, and ML tests found statistical heterogeneity between determined IV estimates. The leave-one-out analysis also indicated the sensitivity of the SNPs (e.g., IBD and PSC, MR-Egger Q = 644.30, p< 0.01; UC and PSC, MR-Egger Q = 378.30, p< 0.01; UC and PSC, MR-Egger Q = 538.50, p < 0.01).
Conclusion:
MR analyses support the positive causal effect of IBD (including UC and CD) on PSC in a European population. We provide suggestions for preventing and treating the two diseases.
More Related Videos
Related Concept Videos
01:17Chronic Bowel Disorders: Introduction
Irritable Bowel Syndrome (IBS) is a common disorder affecting the gastrointestinal tract. The distinctive feature is recurrent abdominal pain associated with altered bowel movements, manifesting as constipation, diarrhea, or fluctuating between both. The...
01:30Inflammatory Bowel Disease II: Crohn's Disease
Inflammatory bowel disease, commonly known as IBD, refers to a collection of disorders that lead to persistent inflammation of the gastrointestinal tract. The two types of IBD are ulcerative colitis, which impacts the colon, and Crohn's disease, which can involve any part of the gastrointestinal segment.
Crohn's disease
Crohn's disease is a chronic, systemic inflammatory bowel disease (IBD) that predominantly affects the gastrointestinal tract. It is marked by...
01:27Inflammatory Bowel Disease I: Ulcerative Colitis
Inflammatory bowel disease, or IBD, encompasses a group of disorders characterized by chronic inflammation or ulceration of the gastrointestinal tract.
Risk Factors
The exact cause of IBD remains unclear, although it is believed to be due to a mix of genetic, environmental, microbial, and immune factors. Genetic factors are significant in determining susceptibility to IBD, with family history being a critical risk factor. Individuals with a first-degree relative who has IBD are at...
01:30Inflammatory Bowel Disease III: Diagnostic Studies and Management I-Nutritional Therapy
Diagnostic studies
A colonoscopy is the definitive screening test, distinguishing ulcerative colitis from other colon diseases with similar symptoms. During a colonoscopy test, inflamed mucosa with exudate ulcerations can be observed, and biopsies are taken to determine the histologic characteristics of the...
01:21Inflammatory Bowel Disease V: Surgical Management
Here are some common surgical interventions for IBD: