Convenient Method of Measuring Baseline Impedance for Distinguishing Patients with Functional Heartburn from those with Proton Pump Inhibitor-Resistant Endoscopic Negative Reflux Disease

Abstract

Background: Combined 24-h intraesophageal pH-multichannel intraluminal impedance (24MII-pH) used for assessing gastroesophageal reflux disease by measuring baseline impedance (BI) requires a 24-h measuring period. In the present study, we developed a quick method of measuring BI and evaluated its usefulness in classifying patients with proton pump inhibitor (PPI)-refractory non-erosive reflux diseases (NERD) as having functional heartburn (FH) or endoscopic-negative reflux disease (ENRD). Methods: Ninety-one NERD patients without esophageal motility disorder underwent 24MII-pH monitoring while on a PPI. The measurements of the mean nocturnal BI (MNBI) and short MNBI were assessed at 3 times (at about 1: 00, 2: 00, and 3: 00 am) for 10 min and 30 s respectively. The measurement of the simple mean BI (MBI) was performed once 30 s at about 11: 00 am. Results: Ninety-one patients were divided into 2 groups: 59 with ENRD and 32 with FH. The cutoff, specificity, and sensitivity for distinguishing patients with FH were as follows: MNBI, 2,874.1 Ω, 72%, and 72%; short MNBI, 2,857.6 Ω, 74%, and 84%; and simple MBI, 2,874.1 Ω, 86%, and 78% respectively. Conclusion: Measuring the simple MBI is a quick method and is useful for distinguishing patients with FH from those in a cohort with PPI-refractory NERD.

Role of the Mean Nocturnal Baseline Impedance in Identifying Evidence Against Pathologic Reflux in Patients With Refractory Gastroesophageal Reflux Disease Symptoms as Classified by the Lyon Consensus

“…37 It is crucial to differentiate non-GERD (ie, FH) patients from GERD (ie, erosive esophagitis and non-erosive reflux disease) patients for prescribing different treatments. The MNBI has proven to be useful in distinguishing FH from GERD [14][15][16][17] and FH from RH, 18,19 with a high diagnostic accuracy off-as well as on-PPI therapy (Table 2), and in predicting symptomatic responses to antireflux therapy. [20][21][22][23] However, no study has explored its role in identifying evidence against GERD in patients with refractory GERD symptoms as classified by the Lyon Consensus, which includes evidence against GERD group, conclusive evidence of GERD group, and inconclusive or borderline evidence of GERD group.…”

“…[9][10][11] Mean nocturnal baseline impedance (MNBI) based on MII-pH monitoring is a novel metric that can be obtained manually in a few minutes using a simple formula and has a very high interobserver reproducibility rate. 6,12 It is considered to be a potential objective reflux metric and a marker that reflects longitudinal reflux burden, mucosal integrity, 13 and the severity of esophageal mucosal damage, which has proved to be useful in both separating refluxunrelated (functional heartburn [FH]) patients from reflux-related (GERD [14][15][16][17] and reflux hypersensitivity [RH] 18,19 ) patients and as an independent potential predictor of symptoms responding to antireflux therapy. [20][21][22][23] Low MNBI is adjunctive evidence for inconclusive or borderline evidence for pathologic reflux (AET 4-6%, reflux episodes 40-80, or Los Angeles [LA] A or B), and can increase the impression of conclusive evidence for pathologic reflux.…”

Mean nocturnal baseline impedance, a novel metric of multichannel intraluminal impedance-pH monitoring in diagnosing gastroesophageal reflux disease

“… 4 , 5 , 15 , 16 , 18 , 19 , 21 – 28 Lower MNBI values have been found in EE, NERD, and reflux hypersensitivity (RH) compared with FH and healthy controls. 4 , 15 , 16 , 18 , 19 , 21 – 23 Also, MNBI was significantly lower in patients with refractory reflux esophagitis than in those with healed reflux esophagitis and NERD, indicating that low MNBI could reflect the severity of esophageal mucosal damage. 16 In addition, it has been proved to be useful in distinguishing GERD from healthy controls, 4 , 15 , 21 and distinguishing reflux-related patients (GERD 16 , 18 , 19 , 22 and RH 22 , 23 ) from reflux-unrelated patients (FH) with a high diagnostic accuracy ( Table 2 ).…”

“… 33 Moreover, previous studies have demonstrated that MNBI can be useful for distinguishing NERD from FH with high AUC, high sensitivity, and specificity off PPI or on PPI therapy ( Table 2 ). 16 , 18 , 19 , 22 …”

The role of advanced endoscopy in the management of inflammatory digestive diseases (upper gastrointestinal tract)

“…10 Furthermore, Yoshimine et al reported that a simple method of measuring impedance at one point during the daytime was useful for distinguishing FH from PPIrefractory NERD. 11 The impedance measurement method will continue to be improved.…”