Outcomes after Negative Impedance-pH Monitoring (MII-pH) in Patients with Functional Heartburn: A Retrospective Chart Review

Abstract

Purpose: In patients with proton pump inhibitor (PPI)-resistant symptoms, evaluation with impedancepH monitoring (MII-pH) is often used to assess whether a relationship exists between symptoms and reflux episodes. Some patients will have a normal number of M-II reflux events and a negative symptomrefl ux association, and may be defined as functional heartburn. The purpose of this study was to asses the outcomes of these patients with negative MII-pH monitoring. Methods: This was a retrospective chart review of all MII-pH studies conducted over a 12-month period at a tertiary referral center. Negative studies were defined as when there was no evidence of increased acid and nonacid events at M-II (total events < 48) and there was a negative association between symptoms and reflux events (Symptom Index scores < 50%). Patient characteristics and clinical outcomes were determined. Results: A total of 108 studies were reviewed, of which 38 were determined to be negative studies based on SI scores and total number of reflux episodes on M-II pH testing. Thirty of these patients were women, eight were men with mean age 49. No patients had a history of esophagitis on past upper endoscopies. Seven patients were on BID dosing of PPI medications, 26 on QD dosing, and five patients were not on any therapy prior to MII-pH testing. Ten studies were done on PPI therapy, and the remainder off. Primary indications for the studies were heartburn, hoarseness and throat clearing. Ninety percent% had previous evaluations with other specialties (ex. ENT, Pulmonary) and/or gastroenterologists for their symptoms. Forty-four percent of patients had a history of concurrent functional GI disorders, and 38% of patients had concurrent diagnosis of depression or anxiety. Follow-up chart reviews revealed 19/38 (50%) were continued on their previous PPI after M-II testing results were completed. Only two of these patients were on a PPI for other indications (PUD, gastric protection). Three patients were placed on agents to modulate visceral hypersensitivity (ex. tricyclics). No patients underwent surgical interventions for their symptoms. Half the patients were able to be contacted on a follow-up phone interview, and 90% reported that their symptoms continued. Conclusion: A high number of patients with PPI-resistant symptoms and negative evaluations with M-II studies for both acid and nonacid reflux remain on PPI therapy, despite no clear evidence of reflux. Better management strategies, appropriate clinical trials and education need to be determined for these patients.