The faecal abundance of short chain fatty acids is increased in men with a non-dipping blood pressure profile

Background and aims: Gut microbiota (GM) has been involved in the pathophysiology of
hypertension (HT), notably via short chain fatty acids (SCFAs). Among the clinical manifestations
of HT, the absence of a significant drop in night-time blood pressure (BP) (also known as the
non-dipping BP profile) has been associated with poor renal and cardiovascular outcomes. The
putative link between GM-derived metabolites and BP dipping status is still unknown.
Methods: Male volunteers (n ¼ 44) were prospectively subjected to 24-hour ambulatory blood
pressure monitoring, stool sample collection and a medical questionnaire. Metabolomics analy ses of stool samples were conducted using Nuclear Magnetic Resonance (NMR).
Results: Higher amounts of acetate, butyrate and propionate were found in the stools of non dippers (n ¼ 12) versus dippers (n ¼ 26) (p ¼ 0.0252, p ¼ 0.0468, and p ¼ 0.0496, respectively; n ¼ 38 in toto). NMR spectral data were not interpretable in 5 dippers and 1 non-dipper. A simi lar significant association was found when including only patients without anti-HT medications (p ¼ 0.0414, p ¼ 0.0108, and p ¼ 0.0602, respectively; n ¼ 21 in toto). A not significant trend was observed when focussing only on HT patients without anti-HT medications (p ¼ 0.0556; n ¼ 14 in toto).
Conclusion: Our pilot study highlights a putative link between GM-derived SCFAs and the BP
dipping status, independently of the BP status itself or the anti-hypertensive medications.