Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical University School of Medicine, Tochigi, Japan.
Omron Healthcare Co., Ltd., Kyoto, Japan.
J Clin Hypertens (Greenwich). 2018 Jun;20(6):1039-1048. doi: 10.1111/jch.13308. Epub 2018 May 30.
Obstructive sleep apnea causes blood pressure (BP) surges during sleep, which may lead to increased sleep-onset cardiovascular events. The authors recently developed an oxygen-triggered nocturnal BP monitoring system that initiates BP measurements when oxygen desaturation (SpO ) falls below a variable threshold. The association between nocturnal BP parameters obtained by nocturnal BP monitoring and simultaneously examined polysomnography-derived sleep parameters in 116 patients with obstructive sleep apnea (mean age 57.9 years, 85.3% men) was studied. In multivariable analysis with independent factors of age, body mass index, sex, and polysomnography-derived measures (apnea-hypopnea index, apnea index, arousal index, lowest SpO , and SpO < 90%), apnea-hypopnea index (β = .26, P = .02) and lowest SpO (β = -.34, P < .001) were independent determinants of hypoxia-peak systolic BP (SBP), defined as the maximum SBP value measured by nocturnal BP monitoring. Similarly, apnea-hypopnea index (β = .21, P = .04) and lowest SpO (β = -.49, P < .001) were independent determinants of nocturnal SBP surge, defined as the difference between the hypoxia-peak SBP and the average of the SBP values within 30 minutes before and after the hypoxia-peak SBP, measured by the fixed-interval function in the manner of conventional ambulatory BP monitoring. In conclusion, in polysomnography-derived parameters, lowest SpO , defined as the minimum SpO value during sleep, is the strongest independent determinant of hypoxia-peak SBP and nocturnal SBP surge measured by nocturnal BP monitoring. Our findings suggest that the severity of the decrease in SpO and the frequency of such decreases would be important indicators to identify high-risk patients who are likely to develop cardiovascular events specifically during sleep.
阻塞性睡眠呼吸暂停（obstructive sleep apnea，OSA）在睡眠期间会导致血压（blood pressure，BP）飙升，从而增加睡眠起始时心血管事件的发生风险。作者最近开发了一种氧触发的夜间 BP 监测系统，当氧饱和度（SpO ）下降到一个可变阈值以下时，该系统会启动 BP 测量。研究人员在 116 例阻塞性睡眠呼吸暂停患者（平均年龄 57.9 岁，85.3%为男性）中，研究了夜间 BP 监测获得的夜间 BP 参数与同时检查的多导睡眠图衍生睡眠参数之间的关联。在多变量分析中，独立因素包括年龄、体重指数、性别和多导睡眠图衍生指标（呼吸暂停低通气指数、呼吸暂停指数、觉醒指数、最低 SpO 和 SpO <90%）。呼吸暂停低通气指数（β=0.26，P=0.02）和最低 SpO （β=0.34，P<0.001）是夜间 BP 监测定义的最大收缩压（systolic blood pressure，SBP）峰值与缺氧相关的独立决定因素。同样，呼吸暂停低通气指数（β=0.21，P=0.04）和最低 SpO （β=0.49，P<0.001）是夜间 SBP 峰值与夜间 BP 监测定义的固定间隔功能测量的 SBP 值在缺氧峰值前后 30 分钟内的平均值之间差值的独立决定因素。总之，在多导睡眠图衍生参数中，最低 SpO （定义为睡眠期间的最低 SpO 值）是夜间 BP 监测测量的最大 SBP 峰值和夜间 SBP 峰值之间差异的最强独立决定因素。我们的研究结果表明，SpO 下降的严重程度和下降的频率可能是确定在睡眠期间更有可能发生心血管事件的高危患者的重要指标。
