Distinct gut microbiome profiles characterize obese and non-obese patients with atherosclerosis: a metagenomic analysis.

BACKGROUND

Obesity is widely recognized as an aggravating risk factor for atherosclerosis (AS), yet the effects of obesity on AS-associated microbiome dysbiosis are not sufficiently characterized. This study aims to identify the contribution of obesity-related dysbiosis in AS.

METHODS

Using shotgun metagenomic sequencing, we studied gut microbiome composition and functional capacity across non-obese AS patients (AS-NOB, BMI < 30, n = 93), age-sex-matched non-obese controls (Ctrl-NOB, BMI < 30, n = 27), and obese AS patients (AS-OB, BMI ≥ 30, n = 68).

RESULTS

Gut community composition differed significantly across study groups (PERMANOVA F = 3.23, p = 0.001). Among metadata, obesity had the strongest effect (F = 3.1, p < 0.01) on the microbiome structure of AS patients. Furthermore, obese AS patients demonstrated a decrease in species richness and evenness (p < 0.05). Taxonomic and functional analysis further suggested that obesity does not simply aggravate AS-associated gut dysbiosis but instead redirects it towards a distinct community state, characterized by a Prevotella expansion that consistently opposes the rest of the bacterial community. Among AS microbiome markers, an increase was detected in Pseudomonadota (Proteobacteria), Bilophila, Dysosmobacter, and Faecalibacterium.

CONCLUSION

Taken together, these results suggest that pathological expansion of Prevotella, potentially in conjunction with reduced alpha diversity, may represent a putative indicator of increased risk in AS patients, particularly within populations where the Prevotella enterotype or subtype is prevalent, warranting further investigation.