Previous studies have shown that pulmonary arterial hypertension patients have different gut bacteria compositions, with lower diversity and fewer anti-inflammatory bacteria that produce beneficial short-chain fatty acids. Could the gut-lung connection contribute to pulmonary arterial hypertension development through enhanced nerve communication and altered bacterial metabolites like trimethylamine-N-oxide?
In this two-sample Mendelian randomization study, recently published in Nutrition & Metabolism, seven specific bacterial types were found to be causally associated with pulmonary arterial hypertension risk using various statistical methods. One bacterial type called UBA7102 sp002315655 appeared to have protective effects against pulmonary arterial hypertension, reducing the odds of disease by 64%. Six other bacterial types were found to increase the risk of pulmonary arterial hypertension: Anaeromassilibacillus sp001305115, CAG-776 sp000438195, F0428, GCA-900,066,495, Leptospirales, and Paenibacillus J. Leptospirales bacteria showed the strongest harmful association, increasing pulmonary arterial hypertension risk by nearly 6-fold, while Paenibacillus J increased risk by more than 3-fold.
Potential treatments could include targeting harmful bacteria specifically, using probiotics or prebiotics to restore healthy gut balance, or fecal microbiota transplantation. The study suggests developing targeted interventions against specific harmful bacteria rather than broad antibiotic treatments that eliminate both good and bad bacteria.
Read more at this link on BMC, Springer Nature
Summary by Suzanne Lea, AfPH volunteer
Her comment (Suzanne is a patient): “Although the sample size was large, there is no mention of the medication used to treat pulmonary arterial hypertension by the patients in the study. From my own experience, the medication can really affect digestion, probably lowering the amount of beneficial gut bacteria and possibly increasing harmful bacteria. Surely this should be a considered factor?”
Citation
Jiang, D., Chang, Y., Zhen, X. et al. The causal effect of gut microbiome on pulmonary artery hypertension based on a two-sample Mendelian randomization study. Nutr Metab (Lond) 22, 86 (2025). https://doi.org/10.1186/s12986-025-00979-0
