Genetically predicted depression linked to multiple gastrointestinal disorders

Genetic predisposition to major depressive disorder has the potential to increase the risk of gastrointestinal disorders such as gastroesophageal reflux disease (GERD), irritable bowel syndrome (IBS), peptic ulcer disease, and nonalcoholic fatty liver disease (NAFLD), according to the results of a Mendelian randomization study.

For the study, researchers obtained genome-wide association data from a meta-analysis (n=480,359) for major depressive disorder, as well as from the UK Biobank (range, n=332,601 to n=486,601) and FinnGen (range, n=187,028 to n=218,792), among individuals of European ancestry for gastrointestinal disorders.

The potential causal relationship between major depressive disorder and gastrointestinal disorders was evaluated using a two-sample Mendelian randomization design.

Inverse-variance weighted analysis showed that genetically predicted major depressive disorder was associated with a heightened risk of four gastrointestinal disorders: GERD, IBS, peptic ulcer disease, and NAFLD. Additionally, reverse Mendelian randomization showed evidence of genetically predicted GERD or IBS increasing the risk of major depressive disorder.

The present data may help establish the mechanisms underlying the comorbidity of major depressive disorder and gastrointestinal disorders. This has important clinical implications, underscoring the need to focus on the symptoms of gastrointestinal disorders in patients with major depressive disorder and the symptoms of emotional problems in patients with gastrointestinal disorders for clinical management.