Communications Technology Group, Aragón Institute of Engineering Research, and CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER_BBN), University of Zaragoza, Zaragoza, Spain.
IEEE Trans Biomed Eng. 2010 May;57(5):1079-88. doi: 10.1109/TBME.2009.2037734. Epub 2010 Feb 5.
In this paper, an analysis of pulse transit time variability (PTTV) during decreases in the amplitude fluctuations of pulse photoplethysmography signal (PPG) (DAP) events for obstructive sleep apnea syndrome (OSAS) screening is presented. The temporal evolution of time-frequency PTTV parameters during DAP was analyzed. The results show an increase in the sympathetic activity index low-frequency component (LF) during DAP for PTTV (85%) significantly higher than for heart rate variability (HRV) (33%), (p < 10(-13)). However, decreases in parasympathetic activity produce lower decrements in high-frequency component (HF) indexes for PTTV (18%) than for HRV (22%). Thus, PTTV reflects sympathetic changes more clearly than HRV. A clinical study was carried out. DAP events were classified as apneic or nonapneic using a linear discriminant analysis from the PTTV indexes. The ratio of DAP events per hour r (DAP), the ratio after filtering based on HRV indexes r (HRV) (DAP), or on PTTV indexes r (PTTV) (DAP), were computed. The results show an accuracy of 75% for r (PTTV) (DAP) (14% increase with respect to r (DAP) and 5% increase with respect to r (HRV) (DAP)), a sensitivity of 81.8%, and a specificity of 73.9% when classifying 1-h polysomnographic excerpts as OSAS or normal. These results suggest that the combination of DAP and PTTV could be better alternative for sleep apnea screening using PPG with the added benefit of its low cost and simplicity.
本文提出了一种分析脉波传导时间变异性（PTTV）的方法，即在脉冲光体积描记信号（PPG）幅度波动降低（DAP）事件期间，用于阻塞性睡眠呼吸暂停综合征（OSAS）筛查。分析了 DAP 期间时频 PTTV 参数的时间演化。结果表明，在 DAP 期间，PTTV 的交感神经活动指数低频成分（LF）增加（85%）明显高于心率变异性（HRV）（33%），（p<10(-13)）。然而，副交感神经活动的减少导致高频成分（HF）指数的降低幅度低于 HRV（22%）。因此，PTTV 比 HRV 更能清晰地反映交感神经的变化。进行了一项临床研究。使用线性判别分析，根据 PTTV 指标将 DAP 事件分类为呼吸暂停或非呼吸暂停。计算了每小时 DAP 事件的比率 r（DAP）、基于 HRV 指标 r（HRV）（DAP）滤波后的比率或基于 PTTV 指标 r（PTTV）（DAP）的比率。结果表明，r（PTTV）（DAP）（75%的准确率）（与 r（DAP）相比增加了 14%，与 r（HRV）（DAP）相比增加了 5%），灵敏度为 81.8%，特异性为 73.9%，当将 1 小时多导睡眠图摘录分类为 OSAS 或正常时。这些结果表明，DAP 和 PTTV 的结合可能是使用 PPG 进行睡眠呼吸暂停筛查的更好选择，其额外的优势是成本低且简单。
