Abstract: Objective To investigate the effect of continuous positive airway pressure(CPAP)treatment on the rise of morning blood pressure in the patients with obstructive sleep apnea and hypopnea syndrome(OSAHS).Methods 105 patients with OSAHSdiagnosed by polysomnography(PSG)were enrolled the study.49 patients were treated with CPAP(CPAPgroup,and the other patients(56 cases)were treated without CPAP(control).The clinical characteristics and PSGdata of all patients were documented,which included age,body height,body weight,neck circumference,abdominal circumference,the family history of hypertension,respiratory disturbance index(RDI),the minimum oxygen saturation(SpO₂)during sleep,percentage of recording time with oxygen saturation of 90% or less(SAT<90),and the longest apnea time.Blood pressure(BP)was recorded in the evening before the sleep and wakefulness from sleep.The definition of morning BPrise is that the patient's morning systolic BP(SBP)or diastolic BP(DBP)was 10 mmHg higher than that of the evening SBPor DBPrespectively.The above data of CPAPgroup were compared with that of the control.After 4～5 weeks' treatment,the above data before and after the treatment were compared and analyzed in CPAP and controls,respectively.Results There is no significant difference between the CPAPand control in clinical information,the morning blood pressure and the PSGresults(P>0.05)before the treatment.After the CPAPtreatment,the morning blood pressure decreased,the percentage of the patients with the rise of morning blood pressure reduced,and the PSGparameters changed for the better in the CPAP group(P<0.05).However,the above parameters after the treatment show no significant difference compared with that before the treatment in control(P>0.05,respectively).Conclusion CPAPtreatment can lower morning BP,and improve PSGparameters in patients with OSAHS.

Key words: sleep apnea and hypopnea syndrome, obstructive, blood pressure, continuous positive airway pressure