Respiratory Department, Hospital Universitario y Politécnico La Fe, Valencia, Spain.
JAMA. 2013 Dec 11;310(22):2407-15. doi: 10.1001/jama.2013.281250.
More than 70% of patients with resistant hypertension have obstructive sleep apnea (OSA). However, there is little evidence about the effect of continuous positive airway pressure (CPAP) treatment on blood pressure in patients with resistant hypertension.
To assess the effect of CPAP treatment on blood pressure values and nocturnal blood pressure patterns in patients with resistant hypertension and OSA.
DESIGN, SETTING, AND PARTICIPANTS: Open-label, randomized, multicenter clinical trial of parallel groups with blinded end point design conducted in 24 teaching hospitals in Spain involving 194 patients with resistant hypertension and an apnea-hypopnea index (AHI) of 15 or higher. Data were collected from June 2009 to October 2011.
CPAP or no therapy while maintaining usual blood pressure control medication.
The primary end point was the change in 24-hour mean blood pressure after 12 weeks. Secondary end points included changes in other blood pressure values and changes in nocturnal blood pressure patterns. Both intention-to-treat (ITT) and per-protocol analyses were performed.
A total of 194 patients were randomly assigned to receive CPAP (n = 98) or no CPAP (control; n = 96). The mean AHI was 40.4 (SD, 18.9) and an average of 3.8 antihypertensive drugs were taken per patient. Baseline 24-hour mean blood pressure was 103.4 mm Hg; systolic blood pressure (SBP), 144.2 mm Hg; and diastolic blood pressure (DBP), 83 mm Hg. At baseline, 25.8% of patients displayed a dipper pattern (a decrease of at least 10% in the average nighttime blood pressure compared with the average daytime blood pressure). The percentage of patients using CPAP for 4 or more hours per day was 72.4%. When the changes in blood pressure over the study period were compared between groups by ITT, the CPAP group achieved a greater decrease in 24-hour mean blood pressure (3.1 mm Hg [95% CI, 0.6 to 5.6]; P = .02) and 24-hour DBP (3.2 mm Hg [95% CI, 1.0 to 5.4]; P = .005), but not in 24-hour SBP (3.1 mm Hg [95% CI, -0.6 to 6.7]; P = .10) compared with the control group. Moreover, the percentage of patients displaying a nocturnal blood pressure dipper pattern at the 12-week follow-up was greater in the CPAP group than in the control group (35.9% vs 21.6%; adjusted odds ratio [OR], 2.4 [95% CI, 1.2 to 5.1]; P = .02). There was a significant positive correlation between hours of CPAP use and the decrease in 24-hour mean blood pressure (r = 0.29, P = .006), SBP (r = 0.25; P = .02), and DBP (r = 0.30, P = .005).
Among patients with OSA and resistant hypertension, CPAP treatment for 12 weeks compared with control resulted in a decrease in 24-hour mean and diastolic blood pressure and an improvement in the nocturnal blood pressure pattern. Further research is warranted to assess longer-term health outcomes.
clinicaltrials.gov Identifier: NCT00616265.
重要性：超过 70%的耐药性高血压患者患有阻塞性睡眠呼吸暂停（OSA）。然而，关于 CPAP 治疗对耐药性高血压患者血压的影响的证据很少。
目的：评估 CPAP 治疗对 OSA 合并耐药性高血压患者血压值和夜间血压模式的影响。
设计、地点和参与者：这是一项在西班牙 24 所教学医院进行的、开放标签、随机、多中心临床试验，采用平行分组、盲终点设计，纳入了 194 例耐药性高血压和 AHI 为 15 或更高的患者。数据收集于 2009 年 6 月至 2011 年 10 月。
干预措施：CPAP 或不治疗，但维持常规降压药物治疗。
主要终点和测量指标：主要终点是 12 周后 24 小时平均血压的变化。次要终点包括其他血压值的变化和夜间血压模式的变化。均进行意向治疗（ITT）和方案分析。
结果：共有 194 例患者被随机分配接受 CPAP（n=98）或不接受 CPAP（对照组；n=96）。平均 AHI 为 40.4（标准差，18.9），每位患者平均服用 3.8 种降压药。基线 24 小时平均血压为 103.4 mm Hg；收缩压（SBP）为 144.2 mm Hg；舒张压（DBP）为 83 mm Hg。基线时，25.8%的患者表现出夜间血压下降模式（与白天平均血压相比，夜间平均血压下降至少 10%）。每天使用 CPAP 4 小时或以上的患者比例为 72.4%。通过 ITT 比较研究期间两组血压变化，CPAP 组 24 小时平均血压（降低 3.1 mm Hg [95%置信区间，0.6 至 5.6]；P=0.02）和 24 小时 DBP（降低 3.2 mm Hg [95%置信区间，1.0 至 5.4]；P=0.005）降幅更大，但 24 小时 SBP 降幅无统计学意义（降低 3.1 mm Hg [95%置信区间，-0.6 至 6.7]；P=0.10）。与对照组相比，CPAP 组在 12 周随访时表现出夜间血压下降模式的患者比例更高（35.9%比 21.6%；调整后的优势比[OR]，2.4 [95%置信区间，1.2 至 5.1]；P=0.02）。CPAP 使用时间与 24 小时平均血压（r=0.29，P=0.006）、SBP（r=0.25；P=0.02）和 DBP（r=0.30，P=0.005）的降低呈显著正相关。
结论和相关性：在 OSA 和耐药性高血压患者中，与对照组相比，CPAP 治疗 12 周可降低 24 小时平均血压和舒张压，并改善夜间血压模式。需要进一步研究以评估更长期的健康结局。
试验注册：clinicaltrials.gov 标识符：NCT00616265。
