How to distinguish PPI-refractory from PPI-responsive patients in gastro-oesophageal reflux-induced chronic cough: post-reflux swallow induced peristaltic wave index and mean nocturnal baseline impedance provide new predictive factors

Wanzhen Li; Bingxian Sha; Haodong Bai; Tongyangzi Zhang; Shengyuan Wang; Yadav Ambedkar Kumar; Yiqing Zhu; Li Yu; Xianghuai Xu

doi:10.1183/23120541.00299-2024

How to distinguish PPI-refractory from PPI-responsive patients in gastro-oesophageal reflux-induced chronic cough: post-reflux swallow induced peristaltic wave index and mean nocturnal baseline impedance provide new predictive factors

ERJ Open Res. 2025 Jan 20;11(1):00299-2024. doi: 10.1183/23120541.00299-2024. eCollection 2025 Jan.

Authors

Wanzhen Li^{1

2}, Bingxian Sha^{1

2}, Haodong Bai^{1

2}, Tongyangzi Zhang¹, Shengyuan Wang¹, Yadav Ambedkar Kumar¹, Yiqing Zhu¹, Li Yu^{1

3}, Xianghuai Xu^{1

3}

Affiliations

¹ Department of Pulmonary and Critical Care Medicine, Tongji Hospital, School of Medicine, Tongji University, Shanghai, China.
² W. Li, B. Sha and H. Bai contributed equally to this article as joint first authors.
³ L. Yu and X. Yu contributed equally to this article as lead authors and supervised the work.

Abstract

Background: The results of empirical trials with proton pump inhibitors (PPIs) for management of gastro-oesophageal reflux-induced chronic cough (GERC) have resulted in considerable controversy, and the mechanism of PPI refractoriness remains unclear. Our study aims to identify the predictors of PPI refractoriness of GERC in a retrospective clinical study.

Methods: In total, 128 GERC patients were enrolled between March 2018 and October 2022. Regression analysis was utilised to create a model for predicting PPI-refractory of GERC using retrospective analysis of the general data and MII-pH indicators.

Results: The post-reflux swallow induced peristaltic wave index (PSPWI) was lower in the PPI-refractory group than the PPI-responsive group (33.89±7.38 versus 39.45±9.47, respectively, p<0.001), as were the mean nocturnal baseline impedance (MNBI) and proximal MNBI (2092.11 (IQR: 652.23)] versus 2426.52 (IQR: 917.39) Ω, respectively, p=0.012; 1599.50 (IQR: 1206.63) versus 2274.50 (IQR: 1775.29) Ω, respectively, p=0.001). Multivariate logistic regression analysis identified the PSPWI (odds ratio 0.919, p=0.001) as an independent predictor of PPI-refractory GERC.

Conclusions: The diagnostic value of both proximal MNBI ≤39.90% and MNBI ≤2233.58 Ω had moderate sensitivity (71.67%) and specificity (75.00%) to identify PPI-refractory GERC.