The Ritchie Centre, Monash Institute of Medical Research, Monash University, Melbourne, Australia.
Sleep Med. 2013 Sep;14(9):858-66. doi: 10.1016/j.sleep.2013.01.015. Epub 2013 Jun 13.
Obstructive sleep apnea (OSA) in adults has been associated with hypertension, low baroreflex sensitivity (BRS), a delayed heart rate response to changing blood pressure (heart period delay [HPD]), and increased blood pressure variability (BPV). Poor BRS may contribute to hypertension by impairing the control of blood pressure (BP), with increased BPV and HPD. Although children with OSA have elevated BP, there are scant data on BRS, BPV, or HPD in this group.
105 children ages 7-12 years referred for assessment of OSA and 36 nonsnoring controls were studied. Overnight polysomnography (PSG) was performed with continuous BP monitoring. Subjects were assigned to groups according to their obstructive apnea-hypopnea index (OAHI): primary snoring (PS) (OAHI ≤1event/h), mild OSA (OAHI>1- ≤5events/h) and moderate/severe (MS) OSA (OAHI>5events/h). BRS and HPD were calculated using cross spectral analysis and BPV using power spectral analysis.
Subjects with OSA had significantly lower BRS (p<.05 for both) and a longer HPD (PS and MS OSA, p<.01; mild OSA, p<.05) response to spontaneous BP changes compared with controls. In all frequencies of BPV, the MS group had higher power compared with the control and PS groups (low frequency [LF], p<.05; high frequency [HF], p<.001).
Our study demonstrates reduced BRS, longer HPD, and increased BPV in subjects with OSA compared to controls. This finding suggests that children with OSA have altered baroreflex function. Longitudinal studies are required to ascertain if this dampening of the normal baroreflex response can be reversed with treatment.
成人阻塞性睡眠呼吸暂停（OSA）与高血压、低压力反射敏感性（BRS）、血压变化时心率反应延迟（心动周期延迟[HPD]）以及血压变异性（BPV）增加有关。BRS 较差可能通过损害血压（BP）的控制导致高血压，导致 BPV 和 HPD 增加。尽管患有 OSA 的儿童血压升高，但关于该组的 BRS、BPV 或 HPD 的数据很少。
对 105 名 7-12 岁因 OSA 评估而就诊的儿童和 36 名非打鼾对照者进行了研究。进行了整夜多导睡眠图（PSG）监测和连续血压监测。根据其阻塞性呼吸暂停低通气指数（OAHI）将受试者分为以下组：单纯性打鼾（PS）（OAHI≤1 次/小时）、轻度 OSA（OAHI>1-≤5 次/小时）和中重度（MS）OSA（OAHI>5 次/小时）。使用交叉谱分析计算 BRS 和 HPD，使用功率谱分析计算 BPV。
与对照组相比，OSA 患儿的 BRS 明显降低（两者均为 p<.05），且对自发性 BP 变化的 HPD 反应延长（PS 和 MS OSA，p<.01；轻度 OSA，p<.05）。在所有 BPV 频率中，MS 组的功率均高于对照组和 PS 组（低频[LF]，p<.05；高频[HF]，p<.001）。
与对照组相比，OSA 患儿的 BRS 降低、HPD 延长和 BPV 增加。这一发现表明，患有 OSA 的儿童存在压力反射功能改变。需要进行纵向研究以确定这种正常压力反射反应的抑制是否可以通过治疗逆转。
