Hypothesis: There is an independent association between the different patterns of esophageal acid exposure in gastroesophageal reflux disease and the severity of the disease.
Design: Case-comparison study.
Setting: Department of surgery at a university hospital.
Patients: A group of 401 patients with increased esophageal acid exposure divided into 4 groups according to the pattern of reflux: postprandial (n = 41), upright (n = 74), supine (n = 129), and bipositional (n = 157).
Main outcome measures: The prevalence of mucosal injury and the status of the lower esophageal sphincter and esophageal motility were assessed in each group.
Results: The likelihood of having indicators of the severity of gastroesophageal reflux disease increases progressively from postprandial to upright, supine, and bipositional reflux.
Conclusions: The pattern of esophageal acid exposure in gastroesophageal reflux disease is an objective predictor of the severity of disease and could be used for therapeutic decisions.