Capsaicin cough receptor sensitivity test in children

Capsaicin has been used as a tussive agent in studies in adults to determine cough receptor sensitivity. The aim of this study was to determine the tolerance, repeatability and influence of inspiratory flow on the capsaicin cough receptor sensitivity test in children. Thirty children (mean age 11 yrs; range 6-16 yrs) were tested on two different days, to determine the lowest concentration of capsaicin required to stimulate two or more coughs (cough threshold (Cth)), 2-4 coughs (C2), and five or more coughs (C5). Capsaicin was nebulized through a dosimeter, with an arrangement that allowed the subjects to visualize and regulate their inspiratory flow. Using a constant inspiratory flow of 20 L x min(-1), tests were reproducible for C2, C5 and Cth (doubling dose changes of 1.13, 1.03 and 1.08, respectively). An increase in the inspiratory flow from 20 to 60 L x min(-1) significantly increased C2 (19.5 to 46.8 microM; p=0.016) and C5 (46.8 to 128.8 microM; p=0.008). We conclude that in children, the capsaicin cough challenge test: 1) is well-tolerated; 2) is highly repeatable; and that 3) the inspiratory flow significantly influences cough receptor sensitivity and repeatability of the test and should, thus, be regulated.

This article has been cited by other articles:

				P. A. Newcombe, J. K. Sheffield, E. F. Juniper, J. M. Marchant, R. A. Halsted, I. B. Masters, and A. B. Chang Development of a Parent-Proxy Quality-of-Life Chronic Cough-Specific Questionnaire: Clinical Impact vs Psychometric Evaluations Chest, February 1, 2008; 133(2): 386 - 395. [Abstract] [Full Text] [PDF]

				A. B. Chang, P. G. Gibson, J. Ardill, and L. P. A. McGarvey Calcitonin gene-related peptide relates to cough sensitivity in children with chronic cough Eur. Respir. J., July 1, 2007; 30(1): 66 - 72. [Abstract] [Full Text] [PDF]

				D. J. Eckert, P. G. Catcheside, D. L. Stadler, R. McDonald, M. C. Hlavac, and R. D. McEvoy Acute Sustained Hypoxia Suppresses the Cough Reflex in Healthy Subjects Am. J. Respir. Crit. Care Med., March 1, 2006; 173(5): 506 - 511. [Abstract] [Full Text] [PDF]

				P. V. Dicpinigaitis and R. V. Alva Safety of Capsaicin Cough Challenge Testing Chest, July 1, 2005; 128(1): 196 - 202. [Abstract] [Full Text] [PDF]

				B. Prudon, S. S. Birring, D. D. Vara, A. P. Hall, J. P. Thompson, and I. D. Pavord Cough and Glottic-Stop Reflex Sensitivity in Health and Disease Chest, February 1, 2005; 127(2): 550 - 557. [Abstract] [Full Text] [PDF]

				S S Birring, B Prudon, A J Carr, S J Singh, M D L Morgan, and I D Pavord Development of a symptom specific health status measure for patients with chronic cough: Leicester Cough Questionnaire (LCQ) Thorax, April 1, 2003; 58(4): 339 - 343. [Abstract] [Full Text] [PDF]

				A B Chang, P D Phelan, C F Robertson, R G D Roberts, and S M Sawyer Relation between measurements of cough severity Arch. Dis. Child., January 1, 2003; 88(1): 57 - 60. [Abstract] [Full Text] [PDF]

				A B Chang, V A Harrhy, J Simpson, I B Masters, and P G Gibson Cough, airway inflammation, and mild asthma exacerbation Arch. Dis. Child., April 1, 2002; 86(4): 270 - 275. [Abstract] [Full Text] [PDF]

				C E Brightling, F A Symon, S S Birring, A J Wardlaw, R Robinson, and I D Pavord A case of cough, lymphocytic bronchoalveolitis and coeliac disease with improvement following a gluten free diet Thorax, January 1, 2002; 57(1): 91 - 92. [Abstract] [Full Text] [PDF]

				A. B Chang, P. D Phelan, J. B Carlin, S. M Sawyer, and C. F Robertson A randomised, placebo controlled trial of inhaled salbutamol and beclomethasone for recurrent cough Arch. Dis. Child., July 1, 1998; 79(1): 6 - 11. [Abstract] [Full Text]

				A. B Chang, P. D Phelan, S. M Sawyer, S. Del Brocco, and C. F Robertson Cough sensitivity in children with asthma, recurrent cough, and cystic fibrosis Arch. Dis. Child., October 1, 1997; 77(4): 331 - 334. [Abstract] [Full Text]