Prevalence of possible refractory or unexplained chronic cough (RCC/UCC) from chronic cough (CC) patient survey data in Spain, Italy, France and Germany (EU4)

<bold>Background:</bold> Data on the prevalence and burden of RCC/UCC are limited. <bold>Objective:</bold> Estimate the prevalence and burden of possible RCC/UCC (PRUCC) from previously collected CC patient survey data in EU4. <bold>Methods:</bold> This secondary analysis of survey data includes CC patients (self-reported cough >8 weeks) without smoking (from 1 year ago), lung cancer, interstitial lung disease, use of ACE-inhibitors or >2 weeks of oral steroids. Patients who received medications (Rx) for ≥1 of 3 CC-related conditions (asthma, GERD, post-nasal drip), did not report a great deal of relief from the Rx, and had a cough severity score ≥4 out of 10 were identified as group 1. Of group 1, patients receiving Rx for ≥2 and 3 CC-related conditions were categorized as groups 2 and 3 respectively, with groups 1-3 deemed PRUCC. Those not in group 1 were deemed CC patients without RCC/UCC (non-PRUCC). Patient characteristics were compared between PRUCC and non-PRUCC. <bold>Results:</bold> Of 591 EU4 adults with CC who completed the survey, 165 (27.9%) were in group 1, 56 (9.5%) in group 2, 11 (1.9%) in group 3, and 426 (72.1%) were non-PRUCC. Compared to non-PRUCC, groups 1 and 2 were similar in age (52 and 52 vs 51 years, p>0.55), but more likely to be female (67% and 75% vs 57%, p<0.04); had worse quality of life (QoL, e.g., worse EuroQoL 5-Dimension [0.72 and 0.66 vs 0.80] and Leicester Cough Questionnaire scores [13.5 and 12.6 vs 16.0]), and had more healthcare visits in the past 6 months (9.9 and 11.6 vs 6.3), all p≤0.001. <bold>Conclusion:</bold> PRUCC prevalence was 28% in the EU4 CC patient survey. PRUCC had worse QoL and more healthcare visits than non-PRUCC.