Schwarz Esther I, Schlatzer Christian, Rossi Valentina A, Stradling John R, Kohler Malcolm
Sleep Disorders Center and Pulmonary Division, University Hospital of Zurich, Zurich, Switzerland.
National Institute for Health Research, Oxford Biomedical Research Centre, Oxford University Hospitals NHS Foundation Trust and University of Oxford, Oxford, England.
Chest. 2016 Dec;150(6):1202-1210. doi: 10.1016/j.chest.2016.07.012. Epub 2016 Jul 21.
Based on meta-analyses, the BP-lowering effect of CPAP therapy in patients with OSA is reported to be approximately 2 to 3 mm Hg. This figure is derived from heterogeneous trials, which are often limited by poor CPAP adherence, and thus the treatment effect may possibly be underestimated. We analyzed morning BP data from three randomized controlled CPAP withdrawal trials, which included only patients with optimal CPAP compliance.
Within the three trials, 149 patients with OSA who were receiving CPAP were randomized to continue therapeutic CPAP (n = 65) or to withdraw CPAP (n = 84) for 2 weeks. Morning BP was measured at home before and after sleep studies in the hospital.
CPAP withdrawal was associated with a return of OSA (apnea-hypopnea index [AHI] at a baseline of 2.8/h and at follow-up of 33.2/h). Office systolic BP (SBP) increased in the CPAP withdrawal group compared with the CPAP continuation group by +5.4 mm Hg (95% CI, 1.8-8.9 mm Hg; P = .003) and in the home SBP group by +9.0 mm Hg (95% CI, 5.7-12.3 mm Hg; P < .001). Office diastolic BP (DBP) increased by +5.0 mm Hg (95% CI, 2.7-7.3 mm Hg; P < .001), and home DBP increased by +7.8 mm Hg (95% CI, 5.6-10.4 mm Hg; P < .001). AHI, baseline home SBP, use of statin drugs, sex, and the number of antihypertensive drugs prescribed were all independently associated with SBP change in multivariate analysis, controlling for age, BMI, smoking status, diabetes, and sleepiness.
CPAP withdrawal results in a clinically relevant increase in BP, which is considerably higher than in conventional CPAP trials; it is also underestimated when office BP is used. Greater OSA severity is associated with a higher BP rise in response to CPAP withdrawal.
ClinicalTrials.gov; No.: NCT01332175 and NCT01797653) URL: www.clinicaltrials.gov and ISRCTN registry (ISRCTN 93153804) URL: http://www.isrctn.com/.
基于荟萃分析，据报道持续气道正压通气（CPAP）疗法对阻塞性睡眠呼吸暂停（OSA）患者的降压效果约为2至3毫米汞柱。该数值来自异质性试验，这些试验常受CPAP依从性差的限制，因此治疗效果可能被低估。我们分析了三项随机对照CPAP撤机试验的晨起血压数据，这些试验仅纳入CPAP依从性良好的患者。
在这三项试验中，149例接受CPAP治疗的OSA患者被随机分为两组，一组继续接受治疗性CPAP（n = 65），另一组停止使用CPAP（n = 84），为期2周。在医院进行睡眠研究前后，患者在家中测量晨起血压。
停用CPAP与OSA复发相关（呼吸暂停低通气指数[AHI]基线时为2.8次/小时，随访时为33.2次/小时）。与继续使用CPAP组相比，停用CPAP组的诊室收缩压（SBP）升高了+5.4毫米汞柱（95%置信区间，1.8 - 8.9毫米汞柱；P = .003），家庭自测SBP升高了+9.0毫米汞柱（95%置信区间，5.7 - 12.3毫米汞柱；P < .001）。诊室舒张压（DBP）升高了+5.0毫米汞柱（95%置信区间，2.7 - 7.3毫米汞柱；P < .001），家庭自测DBP升高了+7.8毫米汞柱（95%置信区间，5.6 - 10.4毫米汞柱；P < .001）。在多变量分析中，控制年龄､体重指数､吸烟状况､糖尿病和嗜睡等因素后，AHI､基线家庭自测SBP､他汀类药物的使用､性别以及开具的降压药物数量均与SBP变化独立相关。
停用CPAP会导致临床上显著的血压升高，这一升高幅度远高于传统CPAP试验中的数值；使用诊室血压测量时，该升高幅度也会被低估。OSA严重程度越高，停用CPAP后血压升高幅度越大。
ClinicalTrials.gov；编号：NCT01332175和NCT01797653）网址：www.clinicaltrials.gov以及国际标准随机对照试验编号注册库（ISRCTN 93153804）网址：http://www.isrctn.com/ 。
