GLP-1 Receptor Agonists and Risk of Paralytic Ileus: A drug-target Mendelian Randomization Study

Paralytic ileus (PI), a condition characterized by reduced bowel motor activity without physical obstruction, can be affected by complications from type 2 diabetes (T2D) and anti-diabetic medications. It is unclear of the causal associations of glucagon-like peptide-1 receptor agonists (GLP-1RAs) with the risk of PI in the context of T2D management.

To investigate the causal relationship of GLP-1RAs with PI, we conducted a 2-sample mendelian randomization (MR) study based on summary statistics from genome-wide association studies (GWAS). Genetic variants in the GLP1R were identified as genetical proxies of GLP-1RAs by the glycemic control therapy, based on genetic associations with glycated hemoglobin (GWAS n=344,182) and T2D (n_{cases/controls}=228,499/1,178,783). The effects of GLP-1RAs were estimated for PI risk (n_{cases/controls}=517/182,423) using GWAS data from the FinnGen project.

Based on MR analysis, GLP-1RAs are causally associated with a decreased risk of PI (OR per 1 mmol/mol decrease in glycated hemoglobin: 0.21; 95% confidence interval [CI]=0.06-0.69). The magnitude of these benefit exceeded those expected from improved glycemic control more generally.

Our study's findings show that GLP-1RAs are causally associated with a lower risk for PI, which provides information to guide clinicians in the selection of appropriate therapies for individuals with T2D while mitigating the risk of developing PI. Investigating the underlying mechanisms that contribute to the lower PI risk associated with GLP-1RAs is essential for a deeper understanding of these associations.