Major depressive disorder and chronic gastritis: A bidirectional two-sample Mendelian randomization study

Area of Science:

• Gastroenterology and Psychiatry
• Genetic Epidemiology

Background:

• Observational studies suggest a link between chronic gastritis (CG) and major depressive disorder (MDD).
• Establishing a causal relationship and temporal sequence between CG and MDD has been challenging.
• Mendelian randomization (MR) offers a method to investigate potential causal links using genetic variants.

Purpose of the Study:

• To investigate the potential causal relationship between chronic gastritis and major depressive disorder.
• To determine if MDD causally affects CG risk.
• To assess if CG causally affects MDD incidence.

Main Methods:

• A bidirectional two-sample Mendelian randomization (MR) approach was utilized.
• Genetic variants for MDD and CG were extracted from large genome-wide association studies (GWAS) of European descent.
• MR estimations and sensitivity analyses were performed to validate findings.

Main Results:

• Genetic liability to major depressive disorder (MDD) was causally associated with an increased risk of chronic gastritis (CG) (OR = 1.33, P = 1.06 × 10-4).
• No significant evidence was found for a causal effect of chronic gastritis (CG) on the incidence of major depressive disorder (MDD) (OR = 1.01, P = 0.68).
• The study used 221 genetic variants for MDD and 5 for CG.

Conclusions:

• Major depressive disorder (MDD) may causally increase the risk for developing chronic gastritis (CG).
• Chronic gastritis (CG) does not appear to have a causal impact on the development of major depressive disorder (MDD).
• Findings may inform clinical management strategies for patients with comorbid MDD and CG.