Hyogo Prefectural Amagasaki General Medical Center, Department of Otolaryngology, Head and Neck Surgery, Japan.
Biomed Phys Eng Express. 2020 Jan 30;6(1):015034. doi: 10.1088/2057-1976/ab6e1c.
To evaluate the effects of a foot bath on autonomic nervous system (ANS) activities as measured by pupil light reflex (PLR) and heart rate variability (HRV) in healthy adults.
PLR and HRV were assessed before and during a foot bath in healthy subjects (n = 110). The subjects dipped their feet in 40 °C water at a level below their knees for 15 min The light reflex in PLR was elicited at four ascending stimulus intensities. Linear-mixed effect models were fit with PLR parameters, and a Wilcoxon signed-rank test with HRV parameters. In PLR analysis, an interaction term between the foot bath intervention and the stimulus intensity was included as a fixed effect.
The PLR analysis showed significant interactions in five out of seven parameters. The altered patterns indicated enhanced activity of the parasympathetic nervous system (PNS) due to the intervention. In contrast, the HRV analysis showed few alterations of PNS activities due to the intervention.
The study results demonstrated differences in altered PNS activity during a foot bath, when assessed by PLR and HRV. In PLR, the stimulus intensity was a crucial factor for the evaluation of foot bath effects. Taken together, the combination of PLR and HRV effectively evaluates ANS activities during a foot bath.
评估足浴对自主神经系统（ANS）活动的影响，采用瞳孔光反射（PLR）和心率变异性（HRV）作为测量指标。
本研究纳入 110 例健康受试者，在足浴前后评估其 PLR 和 HRV。受试者将双脚浸入 40°C 水内，水位低于膝盖，持续 15 分钟。PLR 的光反射在 4 个递增的刺激强度下诱发。采用线性混合效应模型分析 PLR 参数，并采用 Wilcoxon 符号秩检验分析 HRV 参数。在 PLR 分析中，将足浴干预与刺激强度之间的交互项作为固定效应纳入模型。
PLR 分析显示，在七个参数中有五个表现出显著的交互作用。改变的模式表明，由于干预，副交感神经系统（PNS）的活动增强。相比之下，HRV 分析显示，干预对 PNS 活动的改变较少。
本研究结果表明，通过 PLR 和 HRV 评估，足浴期间 PNS 活动的改变存在差异。在 PLR 中，刺激强度是评估足浴效果的关键因素。综上所述，PLR 和 HRV 的结合可有效评估足浴期间的 ANS 活动。
