- CONDITION CENTERS
Acid gastroesophageal reflux commonly causes chronic cough, and response to acid suppression therapy generally is lower than it is in patients with heartburn. Improvement after antireflux surgery suggests involvement of a nonacidic gastric component in the refluxate. As reported in the April 2005 issue of Gut, in a study involving 28 patients who were evaluated using 24-hour ambulatory pressure-pH-impedance monitoring, Daniel Sifrim, MD, PhD, and colleagues investigated whether chronic cough is associated with weakly acidic reflux. Manometry for precise recognition of cough and impedance-pHmetry were used to detect acidic (pH <4), weakly acidic (pH 4-7), and weakly alkaline (pH ≥7) reflux.
Most coughs (69.4%) were considered independent of reflux, and 31% occurred within 2 minutes of a reflux episode; 49% of these were reflux-cough sequences involving acidic (65%), weakly acidic (29%), and weakly alkaline (6%) reflux. Positive symptom association probability between reflux and cough was observed in 10 patients (45%; 5 acidic, 2 acidic and weakly acidic, 3 weakly acidic). This methodology allowed for the precise determination of temporal associations between cough and gastroesophageal reflux and identified a subgroup of patients who had chronic cough associated with weakly acidic gastroesophageal reflux.