The Role of Gastroesophageal Reflux in Exercise-Triggered Asthma: A Randomized Controlled Trial

Background Exercise-triggered asthma (ETA) develops when physical activity triggers asthma symptoms during or directly after exercise. In patients prone to symptoms of supra-esophageal reflux, exercise may trigger gastroesophageal reflux (GER), resulting in such symptoms. Aims To determine the prevalence of abnormal pH in patients with ETA and to determine whether acid suppression improves symptoms in ETA patients. Methods We performed a randomized double-blind trial of rabeprazole versus placebo in the treatment of patients with ETA. Patients underwent treadmill protocol to determine their VO_2max. Next, pH testing was initiated while undergoing a 30-min treadmill program exercising them at 65% of their VO_2max. They were subsequently randomized to rabeprazole or placebo for 10 weeks. At the end of 10 weeks, exercise testing was repeated. Results A total of 31 patients completed the study (20 asthmatics, 11 non-asthmatics). Twenty-two out of 30 (73%) subjects had abnormal pH studies. For all subjects, rabeprazole improved symptoms more than placebo (P = 0.03). The association was stronger in the pH-positive group (P = 0.009). Conclusion Acid reflux is common in ETA patients. Many patients with exercise-related respiratory symptoms are misdiagnosed as chronic asthmatics. Exercise-related symptoms improve with the use of acid suppression. This study suggests that ETA patients may benefit from acid suppression.