How accurate is PPI test in GERD, chest pain diagnosis?

Use of the proton pump inhibitor (PPI) test showed acceptable sensitivity but poor specificity in diagnosing gastroesophageal reflux disease (GERD), a study has shown. The test, however, works better in GERD-related noncardiac chest pain (NCCP).

A team of investigators searched the databases of Medline, Central, and Web of Science for studies reporting the diagnostic accuracy of the PPI test in adult patients with typical GERD and NCCP, who underwent assessment using an accepted reference standard from 1 January 1950 to 1 February 2021.

In addition, the team conducted subgroup analyses and measured the risk of bias using the Quality Assessment of Diagnostic Accuracy Studies-2 tool.

Nineteen studies (11 on GERD and eight on NCCP), which included a total of 1,691 patients, met the eligibility criteria.

PPI test in GERD demonstrated a pooled sensitivity of 79 percent (95 percent confidence interval [CI], 72‒84) and pooled specificity of 45 percent (95 percent CI, 40‒49). In NCCP the pooled sensitivity and specificity were 79 percent (95 percent CI, 69‒86) and 79 percent (95 percent CI, 69‒86), respectively.

For erosive reflux disease (ERD), the pooled sensitivity and specificity of the PPI test were 76 percent (95 percent CI, 66‒84) and 30 percent (95 percent CI< 8‒67), respectively. For nonerosive reflux disease (NERD), the test showed a pooled sensitivity of 79 percent (95 percent CI, 70‒86) and a pooled specificity of 50 percent (95 percent CI, 39‒61).

“Diagnostic accuracy was comparable in ERD and NERD,” the investigators said.