[Validation of the Chinese version of Hull airway reflux questionnaire and its application in the evaluation of chronic cough].

OBJECTIVE: To validate the effectiveness, repeatability and treatment responsiveness of the Chinese version of Hull airway reflux questionnaire (HARQ), and to determine its clinical value.

METHODS: A standard Chinese version of HARQ was developed by an established translation procedure and its repeatability was assessed in a preliminary study involving 55 untreated patients with stable chronic cough. Thereafter, a total of 132 patients with chronic cough referred to our respiratory clinic were recruited into the study between May 2014 and April 2015. After their cough was evaluated with the HARQ, cough symptom score or cough reflex sensitivity to inhaled capsaicin and the correlations among them were analyzed, and the causes of chronic cough in all the patients were presumptively determined according to an established diagnostic protocol and finally confirmed with the subsequent therapy specific to the etiologies. After two weeks of effective treatment, HARQ, cough symptom score and cough reflex sensitivity to inhaled capsaicin were measured once more, and treatment responsiveness was calculated. The score of the HARQ in 132 patients with chronic cough were compared with that in 104 healthy volunteers.

RESULTS: The repeatability of the Chinese version of the HARQ was validated at a week interval with the intraclass correlation coefficients of 0.96 (95%CI: 0.93-0.98, P=0.00) for total score (n=55). No correlation was found between the HARQ and cough symptom score, and the HARQ showed a weak negative correlation with cough threshold C2 (rIgC2=-0.23, P=0.01) but not with C5. The value of HARQ was significantly higher in patients with chronic cough than in healthy volunteers[20.00(14.00, 28.00) vs 4.00 (2.00, 6.00), Z=-12.89, P=0.00], but no difference of HARQ in gender or age existed in chronic cough. Although all the patients with various etiologies of chronic cough had an increased value of HARQ, cough due to gastroesophageal reflux showed the highest HARQ score among them[28.50 (25.00, 32.25) vs 18.50 (14.00, 26.25), Z=4.43, P=0.00]. After two weeks of effective treatment, the HARQ score decreased from 20.00 (14.00, 28.00) pre-treatment to 10.00 (4.25, 17.75) post-treatment (Z=-6.06, P=0.00), with 52.04% of score change ratio, 1.38 of effect side and 1.97 of standard response mean respectively.

CONCLUSION: HARQ is a reliable and valid tool for the management of chronic cough with good treatment responsiveness, and may be used as an easy way to predict cough due to gastroesophageal reflux.