Causal link between mental disorders and gastrointestinal diseases: a Mendelian randomization study

Area of Science:

• Neuroscience
• Gastroenterology
• Genetics

Background:

• Observational studies suggest a link between mental and gastrointestinal diseases.
• The causal relationship between these conditions remains unclear.
• This research investigates potential causal links using genetic data.

Purpose of the Study:

• To determine if common mental diseases causally influence the risk of gastrointestinal diseases.
• To explore the genetic basis of the association between mental and gastrointestinal conditions.
• To provide evidence for targeted interventions and disease prevention strategies.

Main Methods:

• Utilized a two-sample Mendelian randomization (MR) analysis.
• Selected single-nucleotide polymorphisms (SNPs) from genome-wide association studies (GWAS).
• Analyzed associations between Alzheimer's disease, depression, major depressive disorder, Parkinson's disease, schizophrenia, and gastritis/duodenitis, gastric cancer, employing MR-PRESSO for outlier removal and eight MR methods for robustness.

Main Results:

• Identified a causal link between Parkinson's disease and an increased risk of gastric cancer (OR = 0.929 [95% CI = 0.869-0.992], p = 0.029) using the inverse variance weighted (IVW) method.
• Found no significant causal evidence for other mental diseases influencing gastrointestinal disease risk.
• Robustness analyses confirmed the primary findings.

Conclusions:

• Parkinson's disease is causally associated with an increased risk of gastric cancer.
• No causal link was established between other common mental diseases and gastrointestinal diseases.
• Further research is needed to elucidate the mechanisms underlying the observed association and explore other potential connections.