Exploration Of Oral Microbiota In Patients With Obstructive Sleep Apnea-Hypopnea Syndrome

Purpose:To explore the alteration of oral microbiota in OSAHS patients and the effect of CPAP treatment on oral microbiota,and to analyze the significance of differences in oral microbiota.Materialsandmethods:Participants included 139 patients with repetitive snoring or clinical complaint of sleep disordered breathing referred to Sleep Medicine Center of the Second Affiliated Hospital of Fujian Medical University,between July 2017 and January 2018.(1)All individuals underwent examination of height,weight,waist circumference,hip circumference,bloodpressure,and testing of polysomnography.Fasting blood and oral mucosal sampleswere collected in the morning at the end of polysomnography.We determined the microbiome composition using Illumina high-throughput sequencing technologyto sequence the 16 S r RNAhypervariable region of all microbiomes in all samples.We examined the fasting levels of cytokine in all participants andinvestigatied the genetic composition of strains in blood.(2)19 OSAHS patients diagnosed by polysomnography were subjected for one night on Auto-CPAP ventilator,and oral mucosal samples were collected in the morning of the second day to analyze the changes of oral microbiota.Result:(1)We detected higher relative abundances of Porphyromonas and Aggregatibacter in patients with OSAHS(P<0.05).High levels of Porphyromonas bacteria were detected in patients with OSAHS with and without HTN(P<0.05).(2)After CPAP treatment,the abundance of Gemelladecreased and that of Staphylococcusincreased(P<0.05).(3)The level of IL-6 in OSAHS patients with high abundance of Porphyromonas was significantly higher than that of those with low abundance group(P<0.05),but there wasno relation of them(r=0.113,P=0.208).There was no correlation between the abundance of Porphyromona and blood pressure of OSAHS patients(r=-0.035,P=0.694(systolic pressure)/r=-0.071,P=0.429(diastolic pressure)).(4)Neither P.gingivalisnor A.actinomycetemcomitans 18 S recombinant DNA genes were detected in the 139 samples.Conclusion:(1)patients with OSAHS experience a change in oral microbiota:the increased abundance of Porphyromonas and Aggregatibacteraccompanied simultaneously with an increased Il-6,but was not associated with hypertension.(2)CPAP treatment could improve oral microbiota in OSAHS patients: the abundance of Gemelladecreased and that of Staphylococcusincreased.(3)the assumption that the entry of periodontal microorganisms and their metabolic products into the blood and causing endothelial injury is considered as the mechanisms that trigger the development of HTN,has not been tested.