Effect of long-term treatment with inhaled budesonide or theophylline on lung function, airway reactivity and asthma symptoms

Abstract

Asthma is characterized by inflammation of the airways and long-term treatment with inhaled glucocorticosteroids improve clinical control in patients previously treated with inhaled rescue beta-2 agonist. We investigated whether the dose of inhaled glucocorticosteroid was related to outcome compared with oral theophylline. Budesonide 800 μg bd, budesonide 200 μg bd, or theophylline (Theo-Dur® 300 mg bd was given double-blind, double-dummy, and randomized, in a parallel group design for 9 months; when therapy was stopped patients were followed for an additional 3 months. Forced expiratory volume in I sec (FEV1), bronchial reactivity, and asthma symptom scores were assessed before entering the study and after 1,2,3,5,7, and 9 months of treatment and monthly after treatment was stopped. Eighty-five patients (38 females and 47 males) were enrolled in the study during 11/2 year. Withdrawal from the study due to exacerbations during the treatment period was significantly increased (P < 0.01) in the theophylline group. After treatment was stopped more patients withdrew in the budesonide group. In the budesonide 800 μg bd group, FEV1 improved significantly after 1 month's treatment (P < 0.01) and persisted throughout the study period. In the budesonide 200 μg bd group, FEV1 improved slightly and reached significance (P=0.05) after 5 months of treatment. In the theophylline group, FEV1 was unchanged during the 9 months of treatment. In both budesonide groups, FEV1 deteriorated significantly (P < 0.01 and P<0.02, respectively) after termination of study medication and reached pretreatment values during the first month. In the budesonide 800 μg bd group, the concentration of histamine causing a 20% fall in FEV1 (PC20) increased significantly (P<0.01) after 1 month's treatment and increased further after 9 months (P < 0.0001), equivalent to two doubling dilutions. In the budesonide 200 μg bd, group PC20 histamine significantly increased (P < 0.005) after 2 months of treatment and remained constant; theophylline was unchanged. After treatment with budesonide 800 μg bd and 200 μg bd were stopped, PC20 decreased significantly (P < 0.002 and P=0.05, respectively) within the first month. PC20 remained unchanged after theophylline was stopped. After budesonide 800 μg bd and 200 μg bd treatment, symptom severity decreased in a dose-related and highly significant manner (P < 0.00001 and P < 0.0001, respectively). With theophylline, asthma symptoms decreased slightly after 1 and 2 months treatment (P < 0.01 and P < 0.02, respectively) and when treatment was stopped no increase in asthma symptoms was evident. Oral theophylline slightly reduced airways symptoms and had no influence on FEV1 and PC20 histamine. Maintenance treatment with inhaled budesonide gave a dose-related reduction in airways obstruction, bronchial reactivity and asthma symptom severity. The efficacy of inhaled corticosteroid was superior to oral theophylline. © 2002 Elsevier Science Ltd.