Authors' Names

Jane ReynoldsFollow

Presentation Type

Oral Presentation

Category

STEM (science, technology, engineering, mathematics)

Abstract/Artist Statement

Cough Desensitization Treatment: Updates from a randomized controlled trial Abstract Chronic cough is estimated to impact approximately 11% of Americans1 and is one of the leading reasons that patients seek medical evaluation2. For approximately 20% of patients, the typical treatments for medical causes of chronic cough fail and they are said to have refractory chronic cough (RCC)3. RCC has negative implications on a patient’s health-related quality of life4. Cough Desensitization Treatment (CDT) is a novel intervention for RCC that combines behavioral cough suppression therapy with systematic desensitization of the cough reflex using controlled amounts of capsaicin (a known cough stimulant). Fourteen patients with RCC participated in a single-blind randomized placebo controlled trial evaluating the effectiveness of CDT. Participants in the treatment group completed six sessions where they were coached to suppress the “urge-to-cough” elicited with incremental doses of nebulized capsaicin vapor. The placebo group inhaled subthreshold doses of capsaicin vapor that did not elicit an urge-to-cough sensation and practiced suppression techniques. Change in health-related quality of life was assessed with the Leicester Cough Questionnaire (LCQ)5at one-week and three-weeks post-treatment. Additional outcomes included urge-to-cough (UTC) testing (perceived UTC and cough frequency when presented with certain stimuli and tasks that commonly cause cough in RCC), and in 24-hour cough frequency monitoring. At one-week post-treatment, 6/8 treatment participants and 2/6 control participants achieved a clinically meaningful improvement in LCQ scores. This change was maintained at the three-week follow up. A mixed effects linear regression model revealed very weak evidence of a difference in LCQ over time between the two groups (F(2,24)=1.58, p-value=0.23). However, the differences were in the direction of higher mean LCQ in the treatment group. Follow-up contrasts were conducted to estimate the change vs. baseline in each group. There was strong evidence of change in the treatment group at one-week post (t(24) = 4.24, p-value < .001) and three-weeks post (t(24) = 4.60, p-value < .001), with estimated mean increases of 2.95 and 3.20 LCQ points higher compared to baseline, respectively. There was very weak evidence of change in the control group at one-week post (t(24) = 1.47, p-value = .310) but moderate evidence of a change at three-weeks post (t(24) = 2.17, p-value = .08), with increases of 1.18 and 1.75 points vs. baseline, respectively. There was strong evidence of a difference over time between the treatment and control groups in total coughs produced during UTC testing (Chi-square(2)=18.0, p-value = 0.0001). Follow-up contrasts were conducted to estimate the change vs. baseline in each group. There was strong evidence of a change in mean cough counts during UTC testing for both groups at one-week post and three-weeks post (p-value Keywords: chronic cough; cough hypersensitivity; cough reflex 1. Song, W., Chang, Y., Faruqi, S., Kim, J., Kang, M., Kim, S., Jo, E., Kim, M., Plevkova, J., Park, H., Cho, S., Morice, A. (2015). The global epidemiology of chronic cough in adults: a systematic review and meta-analysis. European Respiratory Journal, 45(5), 1479-1481, doi:10.1183/09031936.00218714 2. Centers for Disease Control and Prevention. (2017). National Hospital Ambulatory Medical Care Survey. https://www.cdc.gov/nchs/data/nhamcs/web_tables/2017_ed_web_tables-508.pdf 3. Haque, R., Usmani, O., & Barnes, P. (2005). Chronic idiopathic cough: A discrete clinical entity? Chest 127(5), 1710–1713. 
doi: 10.1378/chest.127.5.1710 4. French, C., Irwin, R., Curley, F., & Krikorian, C. (1998). Impact of chronic cough on quality of life. Archives of Internal Medicine, 158, 1657-1661. doi: 10.1001/archinte.158.15.1657 5. Birring, S., Prudon, B., Carr, A., Singh, S., Morgan, M., & Pavord, I. (2003). Development of a symptom specific health status measure for patients with chronic cough: Leicester Cough Questionnaire (LCQ). Thorax 58(4), 339-343. doi: 10.1136/thorax.58.4.339

Mentor Name

Laurie Slovarp

CDT Gradcon2020.mp4 (37586 kB)

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Cough Desensitization Treatment: Randomized Control Trial Update

Cough Desensitization Treatment: Updates from a randomized controlled trial Abstract Chronic cough is estimated to impact approximately 11% of Americans1 and is one of the leading reasons that patients seek medical evaluation2. For approximately 20% of patients, the typical treatments for medical causes of chronic cough fail and they are said to have refractory chronic cough (RCC)3. RCC has negative implications on a patient’s health-related quality of life4. Cough Desensitization Treatment (CDT) is a novel intervention for RCC that combines behavioral cough suppression therapy with systematic desensitization of the cough reflex using controlled amounts of capsaicin (a known cough stimulant). Fourteen patients with RCC participated in a single-blind randomized placebo controlled trial evaluating the effectiveness of CDT. Participants in the treatment group completed six sessions where they were coached to suppress the “urge-to-cough” elicited with incremental doses of nebulized capsaicin vapor. The placebo group inhaled subthreshold doses of capsaicin vapor that did not elicit an urge-to-cough sensation and practiced suppression techniques. Change in health-related quality of life was assessed with the Leicester Cough Questionnaire (LCQ)5at one-week and three-weeks post-treatment. Additional outcomes included urge-to-cough (UTC) testing (perceived UTC and cough frequency when presented with certain stimuli and tasks that commonly cause cough in RCC), and in 24-hour cough frequency monitoring. At one-week post-treatment, 6/8 treatment participants and 2/6 control participants achieved a clinically meaningful improvement in LCQ scores. This change was maintained at the three-week follow up. A mixed effects linear regression model revealed very weak evidence of a difference in LCQ over time between the two groups (F(2,24)=1.58, p-value=0.23). However, the differences were in the direction of higher mean LCQ in the treatment group. Follow-up contrasts were conducted to estimate the change vs. baseline in each group. There was strong evidence of change in the treatment group at one-week post (t(24) = 4.24, p-value < .001) and three-weeks post (t(24) = 4.60, p-value < .001), with estimated mean increases of 2.95 and 3.20 LCQ points higher compared to baseline, respectively. There was very weak evidence of change in the control group at one-week post (t(24) = 1.47, p-value = .310) but moderate evidence of a change at three-weeks post (t(24) = 2.17, p-value = .08), with increases of 1.18 and 1.75 points vs. baseline, respectively. There was strong evidence of a difference over time between the treatment and control groups in total coughs produced during UTC testing (Chi-square(2)=18.0, p-value = 0.0001). Follow-up contrasts were conducted to estimate the change vs. baseline in each group. There was strong evidence of a change in mean cough counts during UTC testing for both groups at one-week post and three-weeks post (p-value Keywords: chronic cough; cough hypersensitivity; cough reflex 1. Song, W., Chang, Y., Faruqi, S., Kim, J., Kang, M., Kim, S., Jo, E., Kim, M., Plevkova, J., Park, H., Cho, S., Morice, A. (2015). The global epidemiology of chronic cough in adults: a systematic review and meta-analysis. European Respiratory Journal, 45(5), 1479-1481, doi:10.1183/09031936.00218714 2. Centers for Disease Control and Prevention. (2017). National Hospital Ambulatory Medical Care Survey. https://www.cdc.gov/nchs/data/nhamcs/web_tables/2017_ed_web_tables-508.pdf 3. Haque, R., Usmani, O., & Barnes, P. (2005). Chronic idiopathic cough: A discrete clinical entity? Chest 127(5), 1710–1713. 
doi: 10.1378/chest.127.5.1710 4. French, C., Irwin, R., Curley, F., & Krikorian, C. (1998). Impact of chronic cough on quality of life. Archives of Internal Medicine, 158, 1657-1661. doi: 10.1001/archinte.158.15.1657 5. Birring, S., Prudon, B., Carr, A., Singh, S., Morgan, M., & Pavord, I. (2003). Development of a symptom specific health status measure for patients with chronic cough: Leicester Cough Questionnaire (LCQ). Thorax 58(4), 339-343. doi: 10.1136/thorax.58.4.339