4-percent AET best predictor of PPI discontinuation

An acid exposure time (AET) of 4.0 percent is a reliable prognostic marker of proton pump inhibitor (PPI) therapy discontinuation, a study has shown. In addition, 96 hours of monitoring works better than 48 hours in predicting PPI cessation.

“Ambulatory reflux monitoring performed off PPI is the gold standard diagnostic test for nonerosive gastroesophageal reflux disease (GERD),” the researchers said. “However, the diagnostic metrics and optimal duration of monitoring are not well defined.”

To address this, a single-arm clinical trial was carried out over 4 years at two centres involving adults with troublesome GERD symptoms and inadequate response to >8 weeks of PPI. Participants went through wireless pH monitoring off PPI for 96 hours. Whether an individual successfully discontinued PPI or resumed therapy within 3 weeks was the primary outcome.

One hundred thirty participants were enrolled, of which 30 percent stopped using PPI. Among the metrics evaluated, total AET of 4.0 percent showed the best predictive ability to discontinue PPI (odds ratio, 2.9, 95 percent confidence interval, 1.4‒6.4; p=0.006). Other AET thresholds and DeMeester score performed comparably.

AET was markedly higher on day 1 of monitoring than with other days. In addition, prognostic performance decreased substantially when only assessing the first 48 hours of monitoring (area under the curve for 96 vs 48 hours, 0.57; p=0.01).

“These data can inform current diagnostic approaches for patients with GERD symptoms who are unresponsive to PPI therapy,” the researchers said.