Effect of continuous positive airway pressure (CPAP) therapy on heart rhythm and blood pressure variability in primary hypertensive patients with obstructive sleep apnea/hypopnea syndrome (OSAHS) / 中华全科医师杂志

ABSTRACT

Objective To investigate the effect of continuous positive airway pressure therapy (CPAP) on heart rhythm and blood pressure variability in primary hypertensive patients with obstructive sleep apnea/hypopnea syndrome (OSAHS).Methods Ninety seven patients with OSAHS and primary hypertension were randomly divided into treatment group (n =49) and control group (n =48).Patients in control group receive antihypertensive medication only,while patients in treatment group received antihypertensive medication in combination with CPAP therapy for 4 weeks.The dynamic electrocardiogram (ESG) and ambulatory blood pressure for 24 h were measured before and after treatment in both groups.Results After CPAP treatment,the night index of standard deviation of the average NN intervals (SDANNniGHt) in treatment group was (89.0 ± 21.4) ms,while the day and night index of square root of the mean squared differences of successive NN intervals (rMSSDday and rMSSDnight) was (35.9 ± 17.2) ms and (45.7 ± 18.3) ms respectively.Compared with those before treatment,the index of SDANNnight was decreased and the indexes of rMSSDday and rMSSDnight were increased (P ＜ 0.01).Compared with control group,the SDANNnight was decreased,and the rMSSDday and rMSSDnight were increased (P ＜ 0.01,P ＜ 0.05).After CPAP treatment,the night index of low-frequency power (LFnight) in treatment group was (15.3 ± 5.7) ms,which was lower than that before treatment,and the night index of high-frequency power (HFnigh) was (16.3-± 8.1)ms,which was higher than that before treatment (P ＜ 0.01);the LFnight in treatment group was decreased and the HFnight was increased (P ＜ 0.01).After CPAP treatment,the day and night indexes of systolic blood pressure (SBPday and SBPnight) and the night indexes of diastolic blood pressure (DBPnigh) t in treatment group were (136.1 ± 13.4) mmHg,(128.7 ± 9.8) mmHg (1 mmHg =0.133 kPa),and(83.7 ±7.2)mmHg respectivley,which were all lower than those in control group (P ＜ 0.05 or P ＜ 0.01).The incidences of morning peak blood pressure and non-dipper hypertension in control group were significantly higher than those in treatment group (P ＜ 0.01).Conclusion CPAP therapy can effectively adjust the heart rate and blood pressure levels in patients with OSAHS and primary hypertension,especially in the night.