Alterations of oral microbiota in patients with obstructive sleep apnea–hypopnea syndrome treated with continuous positive airway pressure: a pilot study

Obstructive sleep apnea–hypopnea syndrome (OSAHS) is an independent risk factor for cardiovascular diseases, including hypertension. In our previous study, it was demonstrated that oral microbiota alteration in patients with OSAHS, particularly in the genera Aggregatibacter and Porphyromonas, may influence the development of hypertension. Continuous positive airway pressure (CPAP) is the main therapy for OSAHS and OSAHS-associated hypertension. However, the role of oral microbiota post CPAP treatment remains unknown. We conducted 16S rDNA pyrosequencing and bioinformatic analyses to compare the bacterial composition of oral specimens from patients with OSAHS before and after overnight CPAP treatment. This approach enabled a relatively comprehensive description of oral microbiota, with decreases in Gemella and increases in Staphylococcus, f_Lachnospiraceae, Parabacteroides, and f_Ruminococcaceae after CPAP treatment. Alteration of oral microbiota may shed new insight on the underlying pathogenesis of OSAHS-associated hypertension.