客观日间嗜睡对阻塞性睡眠呼吸暂停患者心率变异性的影响

目的 由于阻塞性睡眠呼吸暂停（obstructive sleep apnea, OSA）患者的日间嗜睡症状与其心血管事件风险存在潜在关联，本研究以日间多次睡眠潜伏期试验（multiple sleep latency tests, MSLT）评估客观日间嗜睡，探索其与OSA患者心率变异性（heart rate variability, HRV）之间的关系，提示其心血管事件风险增高的可能机制。方法 回顾性分析2019年1月–2022年5月于四川大学华西医院完成整夜多导睡眠监测（polysomnography, PSG）及MSLT的139例OSA患者及35例原发性鼾症患者的资料。依据平均睡眠潜伏期（mean sleep latency, MSL）评估日间嗜睡程度。以MSL<5 min、5～10 min、>10 min为标准，将OSA患者分为重度嗜睡、轻度嗜睡、无嗜睡3个组，比较3个组与原发性鼾症组在睡眠结构、临床资料、HRV等方面的差异，同时分析MSL与HRV指标的相关性。结果 重度嗜睡组与无嗜睡组相比，正常RR间期标准差（standard deviation of all N–...

Effect of Objective Daytime Sleepiness on Heart Rate Variability in Patients With Obstructive Sleep Apnea

  Objective  Excessive daytime sleepiness (EDS) is associated with cardiovascular events in patients with obstructive sleep apnea (OSA). Our study explored the correlation between objective daytime sleepiness assessed with daytime multiple sleep latency tests (MSLT) and heart rate variability (HRV) in OSA patients. The results may provide insight into possible mechanisms underlying increased risk of cardiovascular events in patients with OSA.  Methods  A retrospective analysis was conducted with the data of 139 patients with OSA and 35 patients with primary snoring. All subjects underwent polysomnography (PSG) and MSLT at West China Hospital between January 2019 and May 2022. We used mean sleep latency (MSL) to measure the severity of EDS and to categorize OSA patients into three groups, severe EDS, light EDS, and non-EDS, with MSL of less than 5 minutes, 5 to 10 minutes, and greater than 10 minutes as the respective defining criteria for classification. A comparison of sleep structure, clinical characteristics, and HRV parameters was performed in order to evaluate the difference between OSA subgroups with varying levels of objective EDS and the primary snoring group. In addition, we also analyzed the correlation between MSL and HRV parameters.   Results  Severe EDS patients had higher values of standard deviation of all N–N intervals (SDNN), total spectral power (TOT), and low-frequency power (LF) as compared to non-EDS patients, which was indicative of sympathetic stimulation (P<0.05). Additionally, high-frequency power (HF) was also higher in severe EDS patients, which indicated decreased parasympathetic drive. A significantly positive correlation was found between MSL and the values of SDNN, TOT, LF, and HF in OSA patients.  Conclusion  OSA patients with objective EDS have elevated sympathetic drive and decreased parasympathetic drive. A positive correlation was found between this change in neural activity and the shortening of MSL.