Background: Gastroesophageal reflux (GER) may be a
trigger for asthma and may be clinically silent. Twenty-four–hour
esophageal pH testing accurately diagnoses GER in asthmatics. There are
no reports correlating respiratory symptoms with esophageal acid
events. This study examines the prevalence and severity of GER in
asthmatics with and without reflux symptoms and examines respiratory
symptom correlation with esophageal acid.
esophageal manometry and 24-h esophageal pH tests performed were
reviewed in asthmatics who met entrance criteria from July 1, 1989,
through November 1, 1994. GER was present if esophageal pH tests were
abnormal. Results of esophageal tests were compared for asthmatics with
reflux symptoms and GER and asthmatics without reflux symptoms and GER.
Respiratory symptoms correlated with esophageal acid events if the
esophageal pH was < 4 simultaneously with the respiratory event or
within 5 min before its onset.
Results: Of 199
asthmatics who qualified for analysis, 164 (82%) had reflux symptoms.
The results of 24-h esophageal pH tests were abnormal in 118 of 164
asthmatics with reflux symptoms (72%), compared with 10 of 35
asthmatics without reflux symptoms (29%). Among asthmatics with GER,
119 of 151 respiratory symptoms (78.8%) were associated with
esophageal acid. Seventy-six of 84 reported coughs (90.5%) were
associated with esophageal acid. Theophylline did not alter esophageal
Conclusions: There is a strong correlation
between esophageal acid events and respiratory symptoms in asthmatics
with GER. Respiratory symptom correlation with esophageal acid events
further supports that GER may be a trigger for
GER = gastroesophageal reflux; LES = lower esophageal sphincter;+
Sx GER = asthmatics with reflux symptoms and GER; −Sx
GER = asthmatics without reflux symptoms and GER; UES = upper