Background: Symptomatic response to acid inhibition can be used as a guide in diagnosing patients with reflux symptoms. The proton-pump inhibitor (PPI) omeprazole has been used as such a diagnostic tool. Intragastric acid control with esomeprazole is more effective than other PPIs and has the potential to offer an advance in the diagnostic use of PPIs.
Methods: Patients experiencing heartburn (for > or = 6 months) were studied in this randomized, double-blind, multicenter study. Following a 3-day placebo run-in, 440 patients were randomized to 14 days' treatment with esomeprazole 40 mg once daily (o.d.), esomeprazole 20 mg twice daily (b.i.d.) or placebo. Heartburn symptoms were recorded daily. Endoscopy and 24-h esophageal pH-monitoring were performed to determine the presence of gastroesophageal reflux disease (GERD). The esomeprazole treatment test was considered positive if patients' symptoms improved during the treatment period compared with symptoms recorded on Day 0.
Results: 63 patients were excluded from the analysis due to lack of symptoms on Day 0 or failure to complete pH-monitoring. The sensitivity of an esomeprazole treatment test in confirming GERD increased during the first days of treatment and stabilized between 79% and 86% after 5 days (both esomeprazole arms). The corresponding figure for the placebo arm was 36%. Specificity was variable (24%-65%) for both active treatment and placebo.
Conclusion: A treatment test with esomeprazole 40 mg has a high sensitivity in confirming GERD. Furthermore, the data indicate that 1-week treatment with a once-daily dosage is sufficient to ensure adequate diagnosis.