Khoshoo V, Le T, Haydel RM, Landry L, Nelson C. Chest. 2003;123:1008–1013
Purpose of the Study.
To determine the effect of gastroesophageal reflux (GER) treatment on asthma outcomes.
Forty-six children (5–10.5 years of age) who had received treatment for moderate persistent asthma for at least 2 years and who were being cared for by a specialist were studied.
Subjects were recruited from a pulmonology practice after fulfilling the following inclusion criteria: no family history of asthma or atopy, no personal history of atopy, receiving treatment for asthma (multiple controllers) for at least 2 years, with ≥3 emergency department visits or hospitalization for treatment of asthma in the prior year, nonsmoking parents, no prior history of respiratory syncytial virus bronchiolitis, and able to swallow a pill or capsule. Forty-six children were enrolled and referred to gastroenterologists, to rule out GER disease with esophageal pH (dual-channel) monitoring (for 20–24 hours). Those with abnormal pH probe study results began treatment, including lifestyle changes, prokinetic and proton pump inhibitor treatment, and, if indicated, surgical intervention. Those with normal pH study results were given the option of beginning medical treatment. The subjects were monitored at regular 4-week intervals for an 18-month period, for asthma assessment and adjustment of medications if necessary. The pulmonologist was not blinded with respect to the treatment.
A total of 482 subjects were screened during a 2.5-year period. Twenty-seven of the 46 enrolled patients (59%) had abnormal pH study results, with 18 opting for medical treatment and 9 opting for surgical treatment. Of the 19 with normal pH study results, 8 opted to begin medical treatment. There were no differences in age or gender for any of the groups. The 27 patients who underwent treatment because of abnormal pH study results all were able to reduce (>50%) the amount of asthma medication used. There was no statistical difference in outcomes between the medical and surgical intervention groups. Of those with normal pH study results, the 11 patients who did not begin GER treatment experienced no changes in their asthma medications; however, 2 of 8 patients with normal study results who began empiric GER treatment were able to reduce (70%) their requirements for bronchodilators and inhaled corticosteroids. Among patients with abnormal pH study results, the probability of improvement of asthma after GER treatment was 100%; among those with normal pH study results receiving treatment, the probability of improvement was 25%. The study found what has been shown in adult studies, that treatment of GER disease with either proton pump inhibitors or surgical intervention can improve asthma, in this case by reducing the need for rescue and controller medications. This has not been found for treatment with ranitidine. The authors found pH probe study results to be useful predictors of responses to anti-GER treatment. The study did not answer several questions, including the following. How long should medical GER treatment continue for these patients? Is the prokinetic necessary? How long will asthma improvement continue, with or without treatment? Is surgical intervention superior to medical treatment? What, if anything, in the patient history could indicate the presence or absence of GER and suggest the response to treatment? What effect does this treatment have on lung function and long-term outcomes?
Screening for the presence of GER disease among children with moderate persistent asthma, with pH probe studies, is a useful screening approach. Treatment of asthmatic children with aggressive acid suppression may improve asthma outcomes.
Although the exclusion criteria for this study were extensive, resulting in a rather select study population, this study does demonstrate what has been found among adults, that GER disease may play a role in a significant number of asthma cases and that treatment of GER disease may lead to improvement in asthma outcomes. It also demonstrates that pH probe studies are useful screening tests for such patients, although patient histories would have been helpful in this study.