Cholinerger Tonus und bronchiale Hyperreaktivität bei Patienten mit persistierendem allergischen Asthma bronchiale

Neural mechanisms have long been regarded as factors contributing to the pathogenesis of asthma and involved in airway hyperresponsiveness. The aim of this study was to evaluate if the vagal cholinergic tone in patients with persistent allergic asthma is increased not only in acute asthma and if this cholinergic tone correlates with airway hyperresponsiveness. Methods: The study comprised 22 healthy control subjects and 40 patients with mild and moderate persistent allergic asthma. Diagnosis was established by clinical and functional follow-up: skin prick test, spirometry with bronchodilator response to ipratropium bromide and methacholine challenge testing. Our results showed positive bronchodilator response to ipratropium bromide in all patients with persistent allergic asthma - mean value of FEV 1 increased by 19.14 ± 6.74% (from 12.10 - 37.20%, p < 0.01). Methacholine challenge testing was also positive: mean value of FEV 1 decreased by 25.75 ± 5.16% (from 20.20 - 40.40%, p < 0.01) after inhalation concentrations between 0.03 and 2.0 mg/ml methacholine (PC 2O FEV 1 from 0.026 - 1,914 mg/ml). Correlations between methacholine challenge testing and bronchodilator response to ipratropium bromide were positive, weak and statistically not significant for all parameters. Conclusion: Patients with persistent allergic asthma have increased cholinergic tone, and this tone correlates positive and weak with airway hyperresponsiveness.