Chronic Refractory Cough: Long-Term Outcomes Following Cough Suppression Therapy

Objective: To determine the long-term outcomes of patients with chronic refractory cough (CRC) following treatment cough suppression therapy (CST). Currently, there is a lack of objective data regarding the long-term outcome of behavioral treatment for CRC.

Methods: From the charts of 106 adult patients diagnosed with chronic refractory cough, twenty-four patients were identified as having long-term data at least three months post-CST in the form of otolaryngologic examination, Voice Handicap Index-10 (VHI-10) and Cough Severity Index (CSI) scores. Patients underwent otolaryngologic evaluation and completed the VHI-10 and CSI assessments during pre-treatment, post-treatment, and long-term follow up visits. Patients were also divided into two groups based on their number of comorbidities.

Results: Twenty of the twenty-four patients had significant reduction in cough severity after completing CST (P<0.001). A significant difference was also found in CSI scores from pre-therapy to the long-term follow up visits (P=0.001). No significant difference was found in CSI scores from post-therapy to long-term follow up visits (P=0.93). No significant difference was found in VHI-10 scores over time (P=0.83). No correlation was found between changes in cough and voice severity and number of comorbidities at the tested level.

Conclusions: Findings of no significant change in CRC over the long term compared to post-therapy measures suggest that patients were able to maintain improvement in cough over the long term despite various comorbidities. The current results suggest that cough suppression therapy represents a satisfactory approach to treating CRC and provides patients with an ongoing tool to maintain reduced cough severity. No significant correlations between number of comorbidities and mean CSI or VHI-10 scores were found over the long term.