Gut microbial metabolites, barrier dysfunction, and endotoxemia in men obstructive sleep apnea-associated hypertension

Obstructive sleep apnea (OSA) is frequently accompanied by hypertension, yet gut-related mechanisms remain unclear. We profiled fecal and plasma short-chain fatty acids, markers of intestinal barrier injury and endotoxemia, immune phenotypes, and the fecal microbiome in men classified as non-OSA, OSA, OSA with prehypertension, or OSA with hypertension, and reassessed a subset after three months of continuous positive airway pressure. OSA with hypertension was characterized by reduced fecal acetate and butyrate, elevated intestinal permeability and endotoxin markers, and a higher proportion of Th17 cells. Lipopolysaccharide tracked with blood pressure severity and showed inverse associations with fecal butyrate and positive associations with plasma propionate. Short-term CPAP exposure was accompanied by improved sleep metrics, reduced barrier injury and endotoxemia, increased microbial diversity, and altered systemic SCFA patterns. These findings support a gut barrier-endotoxin framework linking sleep-disordered breathing with hypertensive risk.