Nonasthmatic chronic cough: No effect of treatment with an inhaled corticosteroid in patients without sputum eosinophilia.
BACKGROUND
Inhaled corticosteroids are effective in suppressing a chronic cough without asthma associated with sputum eosinophilia.


OBJECTIVE
To investigate the inflammatory characteristics in the induced sputum of patients with a chronic cough without asthma or known cause and the effects of budesonide treatment on chronic cough in those patients.


METHODS
Forty-four adults (mean [minimu, maximum] age of 45 years [20,75], 28 women, 17 atopic subjects and 32 nonsmokers], with a daily bothersome cough for at least one year and who had no evidence of asthma or other known cause for the cough, were consecutively enrolled. The trial was a randomized, double-blind, controlled parallel group trial of budesonide 400 mg twice daily for two weeks versus placebo. Patients then received open administration of the same dose of budesonide for a further two weeks. Sputum was induced before and at the end of each treatment period. Cough severity was documented by a visual analogue scale.


RESULTS
Thirty-nine (89%) patients produced mucoid sputum after induction on at least one study visit. At baseline, the majority (59%) had a mild elevation in the median proportion of neutrophils (65%). All had elevated fluid phase levels of fibrinogen (3200 mg/L) and albumin (880 mg/L), and high levels of interleukin-8 and substance P. Interleukin-8 correlated with neutrophils (rho=0.72, P<0.001), fibrinogen (rho=0.65, P<0.001), albumin (rho=0.67, P=0. 001) and eosinophil cationic protein (rho=0.60, P=0.001). Substance P correlated with albumin (rho=0.60, P=0.006). No subject had an increase in eosinophils. Treatment with budesonide did not affect cough or sputum measurements.


CONCLUSIONS
Patients with nonasthmatic chronic cough enrolled in this study had evidence of a mild neutrophilia and/or microvascular leakage. Chronic cough did not respond to treatment with budesonide, perhaps because the cause was not associated with sputum eosinophilia.
Pizzichini
M M
MM
University of Santa Catarina (UFSC), Florianopolis, Brazil.
Pizzichini
E
E
Parameswaran
K
K
Clelland
L
L
Efthimiadis
A
A
Dolovich
J
J
Hargreave
F E
FE
D000328:Adult; D000368:Aged; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use*; D019819:Budesonide / Q000627:therapeutic use*; D002908:Chronic Disease; D003371:Cough / Q000188:drug therapy*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D011657:Pulmonary Eosinophilia; D013183:Sputum / Q000166:cytology*
D000893:Anti-Inflammatory Agents; D019819:Budesonide