Perry Sarah, Huckabee Maggie-Lee
Department of Communication Disorders, University of Canterbury Rose Centre for Stroke Recovery and Research at St George's Medical Centre, Leinster Chambers, Level One, 249 Papanui Road, Christchurch 8014, New Zealand.
Respir Physiol Neurobiol. 2017 May;239:70-74. doi: 10.1016/j.resp.2017.02.002. Epub 2017 Feb 12.
The aim of this study was to investigate whether diurnal variation in cough reflex sensitivity exists in healthy young adults when a tidal-breathing method is used. Fifty-three participants (19-37 years) underwent cough reflex testing on two occasions: once in the morning (between 9 am - midday) and once in the afternoon (between 2-5 pm). The order of testing was counter-balanced. Within each assessment, participants inhaled successively higher citric acid concentrations via a facemask, with saline solution randomly interspersed to control for a placebo response. The lowest concentration that elicited a reflexive cough response was recorded. Morning cough thresholds (mean=0.6mol/L) were not different from afternoon cough thresholds (mean=0.6mol/L), p=0.16, T=101, r=-0.14. We found no evidence of diurnal variability in cough reflex testing. There was, however, an order effect irrespective of time of day, confirming that healthy participants are able to volitionally modulate their cough response.
本研究旨在探讨在健康年轻成年人中采用潮气呼吸法时咳嗽反射敏感性是否存在昼夜变化。53名参与者（年龄在19至37岁之间）接受了两次咳嗽反射测试：一次在上午（上午9点至中午），一次在下午（下午2点至5点）。测试顺序采用平衡法。在每次评估中，参与者通过面罩依次吸入浓度逐渐升高的柠檬酸，其间随机穿插生理盐水以控制安慰剂反应。记录引发反射性咳嗽反应的最低浓度。上午咳嗽阈值（平均值 = 0.6mol/L）与下午咳嗽阈值（平均值 = 0.6mol/L）无差异，p = 0.16，T = 101，r = -0.14。我们未发现咳嗽反射测试存在昼夜变化的证据。然而，无论一天中的时间如何，都存在顺序效应，证实健康参与者能够自主调节其咳嗽反应。
