Objective: To explore whether long-term continuous positive airway pressure (CPAP) ventilation is effective to decrease the blood pressure in the patients with obstructive sleep apnea hypopnea syndrome (OSAHS) accompanied with hypertension.
Methods: Literatures of relevant randomized, controlled, prospective, clinical trials 2000 - 2006 in English and Chinese were retrieved from Medline and CNKI based on the criteria: the subjects being patients with OSAHS, the study lasting at least 4 weeks, and the effect on 24 hours ambulatory blood pressure in CPAP group being compared with that in no-CPAP group. The data thus collected underwent meta-analysis.
Result: 471 cases in 7 studies were included. Three of the 7 studies indicated that CPAP ventilation could decrease the diastolic blood pressure in the patients with OSAHS and four studies showed no significant difference in the effect of CPAP on blood pressure between the two groups. From meta-analysis, the weighted mean difference (WMD) in fixed effect model of 24 h diastolic blood pressure (DBP) was -1.78 [95% CI: -3.34, -0.22]; the WMD (fixed) of 24 h systolic blood pressure (SBP) was -0.95 [95% CI: -2.85, 0.94], and the WMD (random) of 24 h mean blood pressure (MBP) was -1.25 [95% CI: -4.00, 1.49].
Conclusion: The long-term CPAP ventilation can decrease the 24 h DBP.