RESUMEN
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.