A study of the changes of nocturnal blood pressure of patients with OSAHS

Objective: To study the changes of nocturnal blood pressure in patients with obstructive sleep apnea/hypopnea syndrome (OSAHS) in comparison with the control group. Methods: Polysomnography (PSG) was done continuously in patients with OSAHS in the whole night. All the blood pressure of patients were collected before sleep and on the next early morning at brachial artery. Statistical analysis was performed. Results: There was compatibility of sex, age and body mass index in different group of patients, i.e mild, moderate and severe OSAS and non OSAHS group. It was found that the blood pressure of the severe OSAS, measured in the next morning, increased from (126.30±15.36/87.00±10.79) mmHg to (132.33±13.82/91.33±9.82) mmHg, which were significantly higher than that measured before sleep. While there was no significant difference in the changes of blood pressure among the mild, moderate group and control group. There was also significant difference of systolic and diastolic pressure after awakening in all the patients of 3 groups. Conclusions: OSAHS is closely associated with hypertension, especially with nocturnal and intractable hypertension. OSAHS is one of the causes or aggravating factors of hypertension and is directly proportional to the severity of OSAHS.