Background Mechanisms underlying blood pressure (BP) changes in obstructive sleep apnoea (OSA) are incompletely understood. We assessed the associations between BP and selected polysomnography (PSG) traits: sleep depth, airflow limitation measurements and OSA-specific hypoxic burden. Methods This cross-sectional analysis included 2055 participants from the Multi-Ethnic Study of Atherosclerosis who underwent PSG and BP measurements in 2010–2013. Sleep depth was assessed using the ‘OR product’, a continuous measure of arousability. Airflow limitation was assessed by duty cycle (Ti/Tt) and % of breaths with flow limitation, and hypoxia by ‘hypoxic burden’. Primary outcomes were medication-adjusted systolic BP (SBP) and diastolic BP (DBP). We used generalised linear models adjusted for age, sex, race/ethnicity, smoking, education, body mass index, alcohol use, periodic limb movements and alternative physiological disturbances. Results The sample had a mean age of 68.4 years and apnoea–hypopnoea index of 14.8 events/hour. Sleep depth was not significantly associated with BP. Every 1 SD increment in log-transformed non-rapid eye movement duty cycle was associated with 0.9% decrease in SBP (95% CI: 0.1% to 1.6%), even after adjusting for sleep depth and hypoxic burden. Every 1 SD increment in log-transformed hypoxic burden was associated with a 1.1% increase in SBP (95% CI: 0.1% to 2.1%) and 1.9% increase in DBP (95% CI: 1.0% to 2.8%) among those not using hypertension medications. Conclusions Higher duty cycle was associated with lower SBP overall and hypoxic burden with higher SBP and DBP among non-BP medication users. These findings suggest changes in both respiratory effort and oxygenation during sleep influence BP.

中文翻译：

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睡眠障碍新措施与血压的关联：动脉粥样硬化的多种族研究

背景 阻塞性睡眠呼吸暂停 (OSA) 中血压 (BP) 变化的潜在机制尚不完全清楚。我们评估了 BP 与选定的多导睡眠图 (PSG) 特征之间的关联：睡眠深度、气流受限测量和 OSA 特定的缺氧负担。方法 该横断面分析包括来自动脉粥样硬化多种族研究的 2055 名参与者，他们在 2010-2013 年接受了 PSG 和 BP 测量。睡眠深度是使用“OR 产品”评估的，这是一种连续测量唤醒能力的方法。气流受限通过占空比 (Ti/Tt) 和流量受限的呼吸百分比进行评估，并通过“缺氧负担”评估缺氧。主要结果是药物调整后的收缩压 (SBP) 和舒张压 (DBP)。我们使用了针对年龄、性别、种族/民族、吸烟、教育、体重指数、饮酒、周期性肢体运动和其他生理障碍。结果 样本的平均年龄为 68.4 岁，呼吸暂停-低通气指数为 14.8 个事件/小时。睡眠深度与血压没有显着相关性。对数转换的非快速眼动占空比每增加 1 个 SD 与 SBP 降低 0.9% 相关（95% CI：0.1% 至 1.6%），即使在调整睡眠深度和缺氧负担后也是如此。对数转换的缺氧负荷每增加 1 个 SD 与 SBP 增加 1.1%（95% CI：0.1% 至 2.1%）和 DBP 增加 1.9%（95% CI：1.0% 至 2.8%）相关。使用高血压药物。结论 在非 BP 药物使用者中，较高的占空比与较低的总体 SBP 和低氧负担相关，SBP 和 DBP 较高。