Hypertensive disorders of pregnancy were more strongly associated with the functional and network profiles than with the community composition of the gut bacteriome: a pilot study.

BACKGROUND: Recent studies implicate that hypertensive disorders of pregnancy (HDP) is associated with gut microbiome. However, the different associations of different microbial features with HDP are little known. This study investigates the different associations of gut bacterial taxonomic composition, functional and network profiles with HDP. METHODS: A case-control study was conducted in Hefei Maternal and Child Health Hospital from February to August 2024. Twenty-four women with HDP and twenty-one normotensive pregnant controls were included. Fecal samples were collected and the bacterial community in fecal samples were measured using high-throughput sequencing targeting the V4 region of the bacterial 16 S rRNA. The taxonomic composition, functional and network profiles of gut bacterial community in both Control and Case groups were determined, and the associations between HDP and gut bacterial profiles were analyzed. RESULTS: There were no significant differences in gut bacterial community composition between the Control and Case groups. However, the Case group had significantly higher relative abundance of functional taxa associated with intestinal inflammation, primary pathogens involved in gastroenteritis and diarrhea. Furthermore, while the Case group exhibited higher network complexity in gut bacterial interactions, it showed lower ecological variability compared to the Control group. Intriguingly, correlation analyses indicated significantly positive associations between HDP and both microbial functional profiles and species interaction intensity, while no significant correlation was observed with taxonomic composition. CONCLUSION: Although the gut microbial composition remained unchanged in hypertensive pregnancies, functional dysbiosis characterized by proinflammatory features and altered ecological network properties were significantly associated with pregnant women's blood pressure. The dissociation between taxonomic profiles and functional profiles, as well as taxon interactions, highlights the importance of microbial function and interactions in the gut microbiome-targeted diagnosis and therapy of HDPs.