In patients with refractory chronic cough, cough desensitization treatment (CDT) exhibits better improvement in cough-related quality of life when compared to both pharmaceutical and behavioral therapies.

This sham-controlled, parallel-cohort, randomized controlled trial was carried out to collect pilot effectiveness data on a novel therapy for refractory chronic cough (RCC).

A total of 21 RCC-affected adults were randomly segregated into twelve sessions of either cough desensitization treatment (CDT; progressive dosages of aerosolized capsaicin while behaviorally suppressing cough; 11 subjects) or a sham therapy (recurrent exposure to aerosolized saline; 9 subjects). Leicester Cough Questionnaire (LCQ) was the key performance indicator.

Secondary outcome measures were cough challenge testing (to gauge cough-reflex sensitivity) and perceived cough intensity using a visual analogue scale (VAS). Follow-up contrasts and mixed effects linear regression were used to analyze the data.

On all measures, the results favored CDT. In the CDT and sham arms, the mean change in LCQ at three weeks after therapy was 6.35 and 2.17, respectively, with one sham participant excluded because his baseline LCQ values were deemed questionable. The CDT group exhibited moderate to strong evidence of better improvement in the total LCQ score as well as the LCQ Physical and Psychological domain scores.

Strong support was obtained for a higher decrease in the urge to cough during CCT in the CDT group, but only weak support for a decrease in the sensitivity of the cough response to capsaicin. Weak evidence suggested that the CDT group experienced a higher drop in the severity of cough.

Despite the study's limitations stemming from its small sample size, the statistics offer additional proof in favor of more investigation on CDT. Compared to the behavioral and existing pharmacological therapies, CDT produced a higher change in the major efficacy measure (LCQ).