Value of the Proton Pump Inhibitor (PPI) Test for Patients with GERD, NCCP, and Extra-Esophageal GERD: A Meta-Analysis

Abstract

Introduction: Administration of high dose proton pump inhibitor (PPI) therapy has been shown to be beneficial for patients with suspected gastroesophageal reflux disease (GERD), non-cardiac chest pain (NCCP) and/or extra-esophageal GERD. A prior meta-analysis in GERD did not show value for the PPI test. Methods: We performed a systematic review of the literature and meta-analysis in order to determine the odds ratio, pooled sensitivity and specificity rates for the PPI test in populations with different symptoms. We used an expert librarian to conduct three searches for GERD, NCCP, and extra-esophageal GERD separately. (Figure) We only included randomized controlled studies randomizing potential subjects to proton pump inhibitor (PPI) compared to placebo therapy. We used random effects models conducted in Comprehensive Meta-Analysis (CMA software, version 3.0) in order to determine pooled odds ratios (OR) and 95% confidence intervals. Results: GERD was diagnosed in all studies by the presence of abnormal endoscopic findings or an abnormal 24-hour ambulatory esophageal pH test. Of the 1327 patients with GERD symptoms, the odds ratio (OR) that the patient had GERD based upon a positive response to PPI was 3.8 based on 8 studies (95% CI 1.8-7.9). However there was significant heterogeneity present (I2=79%) between studies. Of the 131 patients with NCCP, the OR of the patient having GERD based upon the presence of a positive PPI test from 6 studies was 18.7 (95% CI 9.6-36.4, without the presence of heterogeneity (I2 = 0%). For 136 patients with extra-esophageal GERD symptoms based on data from only 2 studies, the OR was 1.7 (95% CI 0.81-3.4, I2= 0%). Pooled sensitivity, specificity and positive predictive values were highest for NCCP (81%, 84%, and 81%) compared to GERD. (Table).Table 1: Sensitivity, Specificity, and Predictive Values for PPI Test in NCCP and GERDFigure 1Conclusion: The PPI test is a useful diagnostic test for patients presenting with GERD, NCCP or extraesophageal symptoms. The highest predictive value appears to be for patients with NCCP.