Clinical Analysis Of The Effect Of Obstructive Sleep Apnea-hypopnea Syndrome On Blood Pressure

Objective The purpose of the study was to investigate the influence of obstructive sleep apnea-hypopnea syndrome on blood pressure in patients with and without hypertension.Methods 112 outpatients and in-patients who visited The Fujian Provincial Hospital from March, 2010 to March, 2011 and underwent polysomnography (PSG) monitoring for a whole night were inclued.The diagnosis of hypertension,OSAHS was separately made basing on《the guideline on prevention and treatment of hypertensiv -es in China》in 2005《,the draft of guideline on diagnosis and treatment of OSAHS》in 2002.Those whose AHI greater than 20 times per hour were diagnosed as moderate-severe OSAHS,including moderate OSAHS patients and severe OSAHS patients,while those whose AHI less than or equal to 20 times per hour were considered as patients without moderate-severe OSAHS,including simple snorers and mild OSAHS patients. And depent on that wether the OSAHS patient was moderate-severe and whether the patient had hypertension ,the whole cases were subgrouped into the following four groups: normotensive patients without moderate-severe OSAHS, normotensive patients with moderate-severe OSAHS, hypertensives without moderate-severe OSAHS and hypertensives with moderate -severe OSAHS.Then the general clinical data,blood pressure, sleep architecture, oxygen saturation indices were compared among these four groups.Results 1.The moderate-severe OSAHS patients had wider neck circumference (P<0.05)and higher rate of male gender(P<0.01) in hypertensives.The hypertensives were obviously older than normotensive patients(P<0.01)in single snorers and mild OSAHS patients; while the hypertensives had an older age,larger BMI(P<0.05)and higher rate of smoking(P<0.01)in moderate-severe OSAHS patients.The hypertensi -ves with moderate-severe OSAHS had statistically wider neck circumference,wider waist circumference,greater BMI and older age ,and more male,smoking,obese patients than the normotensive patients without moderate-severe OSAHS.None of the parameters above differed statistically between the two groups with and without moderate-severe OSAHS in normotensive patients. 2.In hypertensive patients,the diastolic pressure after waking increased in the group with moderate-severe OSAHS comparing with the one without moderate-severe OSAHS(P<0.01), while both pulse pressure before sleep and after waking decreased ,but neither systolic pressure before sleep(P<0.01),systolic pressure after waking nor diastolic pressure before sleep had any statistically blood pressure differences between the two groups.Yet,no blood pressure parameters mentioned above had any statistical differences between the two groups in normotensive patients.3.Regardless of hypertension,apnea-hypopnea index,hypoxemia index,time of oxygen saturation less than ninety evidently increased in the moderate-severe OSAHS group compared with the group without moderate-severe OSAHS(P<0.01),while the mean oxygen saturation,the lowest oxyge -n saturation distinctly decreased(P<0.01).4.Considering the sleep architecture,only the percent of WASO was statistically larger in the moderate-severe OSAHS group than the group without moderate-severe OSAHS in normotensive patients ,while arousal index and the percentage of REM,NREM,Delta ,Stage One,Stage Two showed no statistical differences between the two groups;the percent of Stage Two was obviously larger in the moderate-severe group than the group without moderate-severe group in the hypertensives,while arousal index and the percent of Stage One,Delta,NREM,REM had no statistical differences between the two groups.Conclusions 1.OSAHS is common in male,wide neck circumference patients,and accompanying with components of metabolic syndrome,such as abnormal blood lipid,hypertension,abdominal obesity. 2.OSAHS is closely interrelated with blood pre -ssure in hypertensive patients.The effect of OSAHS on blood pressure shows as that diastolic pressure after waking increases,while both pulse pressure before sleep and after waking decreases and the effect intensifys with the severity of OSAHS.The anoxia in the night-time may be one of the important machanisms of which diastolic pressure fluctuates in hypertensive patients with OSAHS. 3. Both the blood pressure parameters before sleep and after waking shows no obvious interrelations with the severity of OSAHS in normotensive patients.4.Pulse pressure may be a predictor of the severity of OSAHS.