Increased responses to inhaled oxitropium bromide in asthmatic patients with active hepatitis C virus infection.
OBJECTIVE
The interaction between chronic hepatitis C virus (HCV) infection and bronchial asthma is of considerable interest. This study was designed to examine whether differences in airway responses to an inhaled anticholinergic agent exist between asthmatic patients with and without active HCV infection.


METHODS
Controlled cross-sectional analysis.


METHODS
University hospital.


METHODS
Sixteen HCV-negative asthmatic patients and 36 HCV-positive asthmatic patients.


METHODS
All HCV-positive patients received interferon (INF) therapy for 6 months (INF responders, 16 patients; INF nonresponders, 20 patients). No patient had received INF within 3 years of the start of the study.


RESULTS
Airway hyperreactivity to methacholine (ie, the provocative concentration of methacholine causing a 20% fall in FEV(1) [PC(20)]), maximal increase in FEV(1), and forced expiratory flow between 25% and 75% of FVC (FEF(25-75)) after the administration of oxitropium bromide (200 micro g) were examined. At the start of the study, the groups were well-matched with respect to age, body mass index, and baseline lung function, including methacholine PC(20). The mean (SD) increase in FEV(1) after oxitropium bromide administration was significantly greater in patients with active HCV (95 [7] mL) than in HCV-negative asthmatic patients (68 [12] mL) and asthmatic patients with inactive HCV infection (69 [6] mL; p < 0.001). The increase in FEF(25-75) after oxitropium bromide administration was also significantly greater (250 [90] mL/s vs 170 [90] and 180 [80] mL/s, respectively; p < 0.029).


CONCLUSIONS
In patients with asthma, active HCV infection is associated with increased bronchodilator responses to inhaled oxitropium bromide. HCV infection may modulate acetylcholine-mediated airway tone.
Kanazawa
Hiroshi
H
Department of Respiratory Medicine, Graduate School of Medicine, Osaka City University, Osaka, Japan. kanazawa-h@med.osaka-cu.ac.jp
Hirata
Kazuto
K
Yoshikawa
Junichi
J
D000280:Administration, Inhalation; D001249:Asthma / Q000188:drug therapy* / Q000503:physiopathology; D016535:Bronchial Hyperreactivity / Q000503:physiopathology; D003430:Cross-Sectional Studies; D005541:Forced Expiratory Volume; D019698:Hepatitis C, Chronic / Q000150:complications* / Q000503:physiopathology; D006801:Humans; D007372:Interferons / Q000627:therapeutic use; D016210:Methacholine Chloride; D008875:Middle Aged; D010276:Parasympatholytics / Q000008:administration & dosage*; D012602:Scopolamine Derivatives / Q000008:administration & dosage*
D010276:Parasympatholytics; D012602:Scopolamine Derivatives; D016210:Methacholine Chloride; C017590:oxitropium; D007372:Interferons