Clinical

Active HCV infection may increase airway response to asthma treatment

Last Updated: 2004-04-15 12:20:24 -0400 (Reuters Health)

NEW YORK (Reuters Health) - Active hepatitis C virus (HCV) infection may increase the bronchodilator response to inhaled oxitropium bromide in patients with asthma, Japanese researchers report. The mechanism may involve an alteration in acetylcholine-mediated airway tone.

The findings stem from a study of 52 asthma patients, including 20 with active HCV infection, 16 with inactive HCV infection, 16 without HCV infection. In all subjects, several pulmonary function tests were performed before and after oxitropium bromide administration.

Compared with other patients, those with active HCV infection showed a significantly greater increase in FEV1 with oxitropium exposure (p < 0.001), lead author Dr. Hiroshi Kanazawa and colleagues, from Osaka City University, report in the April issue of Chest. This group also experienced a significantly increase in the forced expiratory flow between 25% and 75% of FVC (p < 0.029).

Dr. Kanazawa's group hypothesizes that "CD8+ T lymphocytes activated by chronic HCV infection may induce cholinergic activation in asthma patients, at least in part through M2 [muscarinic] receptor dysfunction," the researchers state. Studies comparing "inflammatory markers and immunologic patterns between asthmatic patients with and without active HCV infection should be performed."

Chest 2004;125:1368-1371.