Study objectives: To investigate the prevalence of gastroesophageal reflux (GER) among patients with asthma and to determine the effect of omeprazole on the outcome of asthma in patients with GER.
Design: A double-blind, placebo-controlled crossover study.
Setting: Asthmatic patients who attended the pulmonary outpatient clinic of Turku University Central Hospital, Finland.
Patients: One hundred seven asthmatic patients.
Interventions: The patients who were found to have GER in ambulatory esophageal pH monitoring were randomized to receive either omeprazole, 40 mg qd, or placebo for 8 weeks. After a 2-week washout period, the patients were crossed over to the other treatment. Spirometry was performed at baseline and immediately after both treatment periods. Peak expiratory values, use of sympathomimetics, and pulmonary and gastric symptoms were recorded daily in a diary.
Results: Pathologic GER was found in 53% of the asthmatic patients. One third of these patients had no typical reflux symptoms. Daytime pulmonary symptoms did not improve significantly (p = 0.14), but a reduction in nighttime asthma symptoms (p = 0.04) was found during omeprazole treatment. In the patients with intrinsic asthma, there was a decline in [corrected] FEV(1) values (p = 0.049). Based on symptom scores, 35% of the patients were regarded as responders to 8-week omeprazole treatment. The reflux (time [percent] of pH < 4) was found to be more severe (p = 0. 002) in the responders.
Conclusions: There is a high prevalence of GER in the asthmatic population. This reflux is often clinically "silent." After an 8-week omeprazole treatment, there was a reduction in nocturnal asthma symptoms, whereas daytime asthma outcome did not improve. There seems to be a subgroup of asthma patients who benefit from excessive antireflux therapy.