Lung function in patients with gastro-esophageal reflux disease and respiratory symptoms

The aim of this study was to investigate lung function in patients with gastro-esophageal reflux disease (GERD) who present respiratory symptoms suggestive of the possibility of co-morbid asthma. The study encompassed 20 patients (9 women and 11 men; age range from 11 to 68 years) diagnosed with GERD and presenting with chronic cough and other non-specific periodic respiratory complaints. The control group consisted of closely gender and age-matched 20 subjects without any gastrointestinal or respiratory symptoms. All patients and control subjects were tested for lung function, which encompassed spirometric and flow-volume variables. We found that none of the GERD patients had lung function abnormalities characteristic of asthma. There were, however, decreases in forced expired volume in 1 s, forced vital capacity, and in maximal instantaneous forced expiratory flows in the GERD patients compared with the healthy subjects. We conclude that cough accompanying GERD is unlikely to be associated with the presence of co-morbid asthma, but rather suggests a mild airway inflammation developing as a sequel of GERD. The corollary is that chronic cough should prompt physician's attention to consider diagnostic work-up toward the possibility of GERD.