Introduction

There are currently no tools to describe the somatic sensations and triggers of cough in patients with refractory or unexplained chronic cough (RUCC). The Sensations Provoking Cough Questionnaire (TOPICQ-15) aims to characterise cough in RUCC versus cough in other respiratory conditions.

Methods

Patients with chronic cough were asked to complete the TOPICQ (n=49), St Georges Respiratory Questionnaire (SGRQ) and cough severity diary (CSD). A subset of patients repeated TOPICQ 5?7 days later. TOPICQ items were reduced using hierarchical and Rasch analysis. Items with poor ?fit? for RUCC were removed to create TOPICQ-15 (n=15; 8 trigger-items and 7 sensation-items).

Results

176 patients (median age 62.0 [19.0?88.0], female 56.3%, median cough duration 5.0yrs [0.3?69.8]) were enrolled across 5 respiratory groups (n=50 RUCC, n=52 ILD, n=47 asthma, n=12 COPD, n=15 bronchiectasis). Median TOPICQ-15 score was significantly higher in RUCC (37.0) vs ILD (24.5, p=0.01) and asthma (7.0, p<0.001), but not bronchiectasis (20.0, p=0.33) or COPD (18.5, p=0.26), perhaps due to small sample size. TOPICQ-15 demonstrated excellent fit to the Rasch model (X2=66.43, p<0.001), and correlated with SGRQ (r=0.47, p<0.001) and CSD (r =0.63, p<0.001). TOPICQ-15 Test-retest reliability (ICC) was excellent (r=0.91, p=<0.001).

Conclusions

High TOPICQ-15 scores in patients with RUCC suggests their cough is characterised by specific sensations and triggers. TOPICQ-15 will be evaluated in a larger cohort of patients presenting with chronic cough and may aid clinical identification of RUCC from cough in other common respiratory conditions.