Study objectives: The effects of gastroesophageal
reflux on airway hyperresponsiveness in patients with bronchial asthma
have yet to be studied in significant detail. The purpose of the
present study was to determine how esophageal acid perfusion could
change airway responsiveness in patients with bronchial asthma.
Patients and interventions: In seven patients with
bronchial asthma (mean ± SD age, 55.1 ± 6.4 years; four women and
three men), esophageal pH was monitored by a pH meter and airway
responsiveness was evaluated by aerosol inhalation of methacholine,
during esophageal perfusion through an esophageal tube filled with
either saline solution or 0.1N hydrochloric acid (HCl), the order of
which was selected at random, in 1-week intervals. Spirometry was also
performed during esophageal pH monitoring.
significant decrease in the geometric mean of airway sensitivity or the
concentration of methacholine causing a 35% fall in respiratory
conductance was observed during esophageal HCl perfusion compared with
that of saline solution perfusion (p < 0.01 or p < 0.003),
although no significant changes were observed in vital capacity,
FEV1, peak expiratory flow, respiratory resistance, or
slope of respiratory conductance during the periods of saline solution
and HCl perfusion.
Conclusion: We concluded that an
increase in airway hyperresponsiveness was induced when HCl stimulated
the esophagus in patients with bronchial asthma. These results
suggest that esophageal reflux is one of the important factors that
aggravate asthmatic status.