Objective: To study the value of airway pH monitoring in determining the association between chronic cough and laryngopharyngeal reflux (LPR) in children.
Methods: A total of 274 children with chronic cough who were treated from January 2016 to December 2019 were enrolled. The DX-pH detection system was used to conduct 24-hour airway pH monitoring. The association between chronic cough and LPR was analyzed.
Results: Among the 274 children, there were 168 boys and 106 girls, with a median age of 62.8 months and a median airway pH value of 7.3. Of all the 274 children, 99 (36.1%) had LPR, and the incidence rate of LPR was 36.9% (62/168) in boys and 34.9% (37/106) in girls (P=0.737). The comparison of the incidence rate of LPR among children aged < 1 year, 1-6 years, and > 6 years showed that the younger children had a significantly higher incidence rate of LPR than the older ones (P=0.003). There was no significant difference in the incidence of LPR between the two groups with chronic cough of unknown etiology and definite etiology. The incidence of chronic cough was positively correlated with that of LPR (rs=0.861, P < 0.01). Among the 99 children with positive RYAN index, 65 (66%) suffered from simple LPR.
Conclusions: LPR is highly associated with the development of chronic cough, and airway pH monitoring may be a safe and effective method for the diagnosis of LPR.
目的: 探讨气道pH值监测在儿童慢性咳嗽与咽喉反流（laryngopharyngeal reflux，LPR）相关性判断中的价值。
方法: 对2016年1月至2019年12月274例慢性咳嗽患儿，采用DX-pH监测仪进行24 h气道pH值监测，分析儿童慢性咳嗽与LPR的相关性。
结果: 274例患儿中，男168例，女106例，中位年龄62.8个月，中位气道pH值为7.3，存在LPR患儿99例（36.1%），其中男孩LPR发生率为36.9%（62/168），女孩为34.9%（37/106），差异无统计学意义（P=0.737）；婴儿期（< 1岁）、幼儿及学龄前期（1~6岁）、学龄期（> 6岁）患儿LPR发生率比较显示，低年龄LPR患儿发生率明显高于高年龄患儿（P=0.003）。慢性咳嗽病因明确与否并不影响LPR发生率（P=0.992），慢性咳嗽与LPR的发生呈正相关（rs=0.861，P < 0.01），RYAN指数阳性患儿中单纯LPR有65例，占比66%（65/99），临床应予以重视。
结论: LPR与慢性咳嗽的发生高度相关，气道pH值监测是诊断LPR安全有效的方法。