New research presented at United European Gastroenterology Week 2019 has found that 18 commonly used drug categories extensively affect the taxonomic structure and metabolic potential of the gut microbiome.
For the study, researchers at the University Medical Center Groningen and the Maastricht University Medical Center in the Netherlands studied the relationship between 41 commonly used drugs and gut microbial changes by performing metagenomics sequencing of 1,883 fresh frozen faecal samples from three independent cohorts: a population-based cohort, patients with inflammatory bowel disease and patients with irritable bowel syndrome intermixed with healthy controls.
Out of 41 drugs categories, 18 were associated with changes in gut microbiota composition and/or function, with proton-pump inhibitors (PPIs), metformin, antibiotics and laxatives having the largest impact. After correcting for polypharmacy, seven drug categories remained significant.
The gut microbiota of PPI users showed increased abundance of upper gastrointestinal tract bacteria and increased fatty acid production, while metformin users had higher levels of Escherichia coli. The use of oral steroids was associated with high levels of methanogenic bacteria, which has been associated with obesity.
The authors also identified an increase in antibiotic resistance mechanisms related to eight different medication categories.