24-hour Multichannel Intraluminal Impedance Research Articles

Pathophysiology of Potassium-competitive Acid Blocker-refractory Gastroesophageal Reflux and the Potential of Potassium-competitive Acid Blocker Test.

Background/AimsPotassium-competitive acid blockers are expected to be the next generation of drugs for the treatment of diseases caused by gastric acid. In 2015, vonoprazan fumarate, a novel potassium-competitive acid blocker, was approved by the Japanese health insurance system. Since its approval, patients refractory to vonoprazan can be encountered in clinical settings. We designed this study to clarify the pathophysiology of gastroesophageal reflux disease refractory to vonoprazan.MethodsIn this retrospective study, we involved patients who had refractory symptoms after administration of standard-dose proton pump inhibitors or vonoprazan and underwent diagnostic testing with esophageal high-resolution manometry and 24-hour multichannel intraluminal impedance and pH monitoring while using proton pump inhibitors or vonoprazan. Patients were diagnosed based on the Rome IV criteria for functional gastrointestinal disorders and diagnostic test results.ResultsTwenty-seven patients were analyzed during this study. Gastric pH ≥4 was sustained for a longer period of time, and the esophageal acid exposure time and number of acid reflux events were shorter in the vonoprazan group than in the proton pump inhibitor group. The percentage of patients diagnosed with acidic gastroesophageal reflux disease in the vonoprazan group was lower than that in the proton pump inhibitor group.ConclusionsIntra-gastric pH and acid reflux were strongly suppressed by 20-mg vonoprazan. When patients with gastroesophageal reflux disease present symptoms after administration of 20-mg vonoprazan, the possibility of pathophysiologies other than acid reflux should be considered.

Su1073 - Assessment of Exhaled Breath Condensate for Non-Invasive Diagnosis of Gastroesophageal Reflux Disease

Introduction: Gastroesophageal reflux disease (GERD) is a disease caused by backflow of gastric contents into the esophagus due to the failure of physiological antireflux mechanisms and can lead to esophageal and extraesophageal symptomatology. Extraesophageal reflux (EER) is a condition where refluxate penetrate above the upper esophageal sphincter in to the oral cavity, pharynx, upper and lower respiratory tract and leads to pathological changes. Monitoring of various parameters in exhaled breath condensate (EBC) in patients suffering from extraesophageal symptoms of GERD is non-invasive and simple approach to assess the gastroesophageal reflux. The aim was to compare the pH and total ionic profile of EBC with 24-hour multichannel intraluminal impedance and pH monitoring (MII-pH) and Peptest in a group of patients with acid reflux (pH<4), weakly acid reflux (pH 4-7) and healthy controls

Association Between Pepsin in the Saliva and the Subjective Symptoms in Patients With Laryngopharyngeal Reflux

Our study was designed to further evaluate the relationships between the saliva pepsin level and the symptoms and quality of life of patients with laryngopharyngeal reflux (LPR). A prospective cohort study without controls. Tertiary teaching hospital. We analyzed 50 patients diagnosed with LPR by 24-hour multichannel intraluminal impedance pH monitoring. All subjects were instructed to collect saliva samples upon waking in the morning. The saliva pepsin levels were analyzed using enzyme-linked immunosorbent assay. The Reflux Symptom Index, Reflux Finding Score, Laryngopharyngeal Reflux-Health-Related Quality of Life, and Short Form 36 survey were administered. The pepsin was detected in the saliva of 41 patients with LPR (17.15 ± 20.42 ng/mL). Nine patients did not have pepsin in the saliva. There were no significant associations between the pepsin level in the saliva and Reflux Symptom Index, Laryngopharyngeal Reflux-Health-Related Quality of Life, or Short Form 36 of patients with LPR. The saliva pepsin level is not significantly correlated with LPR symptoms or quality of life in LPR patients. It may be true that there is no association between pepsin levels and LPR symptoms, but this lack of association does not prove the lack of pathophysiological effect.

Symptom relief and health-related quality of life in globus patients: a prospective study

Globus may be a persistent symptom impairing patients’ quality of life. Diagnostics and treatment are controversial but some globus patients may benefit from reassurance and attention. We investigated how globus symptoms change during a short-term follow-up without any treatment after an examination by an ear, nose and throat (ENT) physician and further diagnostic procedures. We also surveyed whether patients with persistent globus suffer from simultaneous voice problems. The study comprised 30 consecutive globus patients referred to Helsinki University Hospital, Department of Otorhinolaryngology – Head and Neck Surgery. We performed an ENT examination and scored patients’ videolaryngostroboscopies using the Reflux Finding Score (RFS). Patients filled in three questionnaires: the Reflux Symptom Index (RSI), the Deglutition Handicap Index (DHI) and the 15-Dimensional Measure of Health-Related Quality of Life (15-D HRQoL). Patients underwent transnasal esophagoscopy, high-resolution manometry, and 24-hour multichannel intraluminal impedance and pH monitoring. After a four-month follow-up, patients re-answered the same questionnaires and a speech and language pathologist (SLP) examined the patients. Baseline and follow-up questionnaires were available from 27 (90%) patients. According to the RSI (p = .001) and the DHI (p = .003), patients’ symptoms diminished after four months. The 15-D showed improvement in one subscale measuring discomfort and symptoms (p = .023). The SLP examined 23 (77%) patients, finding functional voice problems in six (26%). The study showed that most globus patients felt their symptoms diminished without any treatment during four months. In some patients, coexisting voice problems may be associated with persistent globus.

Severe Delayed Gastric Emptying Induces Non-acid Reflux up to Proximal Esophagus in Neurologically Impaired Patients.

Background/AimsThe aim of this study is to investigate the degree of delayed gastric emptying (DGE) and evaluate how the severity of DGE affects gastroesophageal reflux disease (GERD) in neurologically impaired (NI) patients utilizing 24-hour multichannel intraluminal impedance pH measurements (pH/MII) and 13C-acetate breath test (13C-ABT) analyses.Methods13C-ABT and pH/MII were conducted in 26 NI patients who were referred to our institution due to suspected GERD. At first, correlation analyses were performed to investigate the correlation between the 13C-ABT parameters and the clinical or pH/MII parameters. Thereafter, all patients were divided into 2 groups (DGE and severe DGE [SDGE] group) according to each cut off half emptying time (t1/2, 90–170 minutes). Each pH/MII parameter was compared between the 2 groups in each set-up cutoff t1/2.ResultsThe mean t1/2 of all patients was 215.5 ± 237.2 minutes and the t1/2 of 24 (92.3%) patients were > 100 minutes. Significant moderate positive correlations were observed between both t1/2 and lag phase time and the non-acid reflux related parameters. Furthermore, the patients in the SDGE group demonstrated higher non-acid reflux related parameters than those of the DGE groups when the cutoff was t1/2 ≥ 140 minutes.ConclusionThe present study demonstrated that GE with t1/2 ≥ 140 minutes was related to an increase of non-acid exposure reaching up to the proximal esophagus in NI patients, and indicating that NI patients with SDGE might have a high risk of non-acid GERD.

Acid and nonacid gastroesophageal reflux after single anastomosis gastric bypass. An objective assessment using 24-hour multichannel intraluminal impedance-pH metry

BackgroundSingle anastomosis gastric bypass (SaGB) was introduced in 2001 as an alternative to “loop” gastric bypass. It was considered as a procedure that would eliminate alkaline reflux and associated esophagitis. ObjectivesExisting evidence about the postoperative incidence of gastroesophageal reflux (GERD) after SaGB is based on studies using symptom questionnaires. The aim of our study was to evaluate GERD 12 months after SaGB by using 24-hour multichannel intraluminal impedance pH metry (24-h MIIpH). SettingSurgical department of a university hospital MethodsMorbidly obese candidates for SaGB underwent 24-hour MIIpH prior and 12 months after their bariatric procedure. ResultsThere were 11 patients included in this prospective study. Results of 24-hour MIIpH revealed that DeMeester score (40.48 versus 24.16, P = .339) had an increasing trend 12 months after SaGB. Acid reflux episodes decreased, whereas nonacid reflux episodes increased postoperatively, both in proximal and distal esophagus. Total median bolus clearance time and acid clearance time increased. De novo GERD developed in 2 patients (28.6%) and worsening of already existing GERD developed in all patients with preoperative evidence of GERD. ConclusionThe use of symptom questionnaires to assess postoperative GERD after SaGB may not accurately depict the real image. Twenty-four–hour MIIpH in 12 months after SaGB revealed an increase of total number of nonacid reflux episodes and a decrease of total number of acid reflux episodes, with longer duration of each acid reflux episode. Close postoperative follow-up with reflux testing and possibly endoscopy could eliminate the risk of complicated GERD.

Comparison of Characteristics According to Reflux Type in Patients With Laryngopharyngeal Reflux

Objectives To analyze laryngopharyngeal reflux (LPR) as an acidic, nonacidic, or mixed type according to 24-hour multi-channel intraluminal impedance (MII) pH monitoring and the clinical characteristics of each type.Methods Ninety patients were prospectively enrolled in this study. All patients underwent 24-hour MII pH monitoring as a diagnostic tool. Eighty-three patients were diagnosed with LPR. The patients were classified into three groups according to the pH of the hypopharyngeal probe: the acid reflux group, nonacid reflux group, and mixed reflux group. Subjective symptoms and objective findings were evaluated based on patients’ responses to the Short Form 12 Survey (SF-12), LPR health-related quality of life (LPR-HRQOL), reflux symptom index, and reflux finding score.Results The results of each group were compared. As a result, 34 patients were classified into the nonacid reflux group and 49 into the mixed reflux group. There were no patients classified as having acid reflux alone. There was no significant difference between the two groups when comparing the reflux symptom index, reflux finding score, LPR-HRQOL, or the mental component score of the SF-12. However, the physical component score of the SF-12 was higher in the nonacid reflux group (P=0.018). The DeMeester composite score (P=0.015) and total number of LPR events (P=0.001) were lower in the nonacid reflux group than in the mixed reflux group.Conclusion In conclusion, no LPR patient had only acid reflux. The nonacid reflux LPR patients showed similar clinical characteristics and findings compared to the mixed reflux group, but exhibited significantly fewer LPR episodes.

Sa1165 - Qualitative Evaluation of the Composition of Refluxate by 24-Hour Multichannel Esophageal Intraluminal Impedance and pH-Monitoring and its Relationship to Extraesophageal Reflux Disease

We presented a study focused on qualitative evaluation of the composition of refluxate and its relationship with extraesophageal symptoms. Gastroesophageal reflux disease (GERD) is a disease caused by backflow of gastric contents into the esophagus due to the failure of physiological antireflux mechanisms and can lead to esophageal and extraesophageal symptomatology. Extraesophageal reflux (EER) is a condition where refluxate penetrate above the upper esophageal sphincter (UES) in to the oral cavity, pharynx, upper and lower respiratory tract and leads to pathological changes. The examinations in our study were carried out using 24-hour multichannel intraluminal impedance and pH esophageal monitoring (MII-pH), which compared to the more commonly used conventional pH-monitoring can accurately detect reflux episodes at all pH levels and divide the episodes to acid reflux, weakly acidic reflux and nonacid reflux, and also provides information of the composition of refluxate (liquid, gas and mixture). We evaluated results of the examinations from 200 patients in two groups. The first group included 100 patients with classic GERD and in the second group were 100 patients with EER symptoms. We evaluated DeMeester score, the number of reflux episodes by pH, simultaneously the state of matter and the rate of penetration in the UES area. Patients with EER symptoms have more weakly acid reflux episodes and fewer acid reflux episodes compared to a group of patients with classical GERD symptoms while we found minor differences in the frequency of individual components of refluxate. In the group with EER we also observed lower values of DeMeester score, a higher number of gaseous reflux episodes and generally significantly higher number of penetration of refluxate of all states of matter to the UES area.

Association between 24-hour combined multichannel intraluminal impedance-pH monitoring and symptoms or quality of life in patients with laryngopharyngeal reflux.

To evaluate the association between the parameters of 24-hour multichannel intraluminal impedance (MII)-pH monitoring and the symptoms or quality of life (QoL) in laryngopharyngeal reflux (LPR) patients. Prospective cohort study without controls. University teaching hospital. Forty-five LPR patients were selected from subjects who underwent 24-hour MII-pH monitoring and were diagnosed with LPR from September 2014 to May 2015. Reflux Symptom Index (RSI), Health-related Quality of Life (HRQoL), Short Form 12 (SF-12) Survey questionnaires were surveyed. Spearman's correlation was used to analyse the association between the symptoms or QoL and 24-hour MII-pH monitoring. Most parameters in 24-hour MII-pH monitoring showed weak or no correlation with RSI, HRQoL and SF-12. Only number of non-acid reflux events that reached the larynx and pharynx (LPR-non-acid) and number of total reflux events that reached the larynx and pharynx (LPR-total) parameters showed strong correlation with heartburn in RSI (R = 0.520, P < 0.001, R = 0.478, P = 0.001, respectively). Multiple regression analysis showed that there was only one significant regression coefficient between LPR-non-acid and voice/hoarseness portion of HRQoL (b = 1.719, P = 0.022). Most parameters of 24-hour MII-pH monitoring did not reflect subjective symptoms or QoL in patients with LPR.

Comparison of Esophageal Function Tests in Chinese Patients with Functional Heartburn and Reflux Hypersensitivity.

Objective To investigate the differences in the results of esophageal function tests for functional heartburn (FH) and reflux hypersensitivity (RH). Methods Patients with FH and RH and healthy volunteers (HVs) from the Department of Gastroenterology, Beijing Anzhen Hospital and Beijing Chao-Yang hospital, who underwent high-resolution manometry and impedance (HRIM), and 24-hour multichannel intraluminal impedance and pH recording (MII/pH) between 2014 and 2016, were enrolled in this study. Results 36 HV, 147 FH patients, and 91 RH patients were enrolled. The postreflux swallow-induced peristaltic wave index (PSPW index) and mean nocturnal baseline impedance (MNBI) values were significantly lower in RH than in FH and HV. The ineffective esophageal motility (IEM), fragmented peristalsis rates, total bolus exposure, proximal total reflux events, and distal total reflux events were significantly greater in RH than in FH and HV. Conclusions Compared to HV and FH patients, RH patients exhibited greater IEM and fragmented peristalsis rates, a greater total bolus exposure, more proximal total and distal total reflux events, and reduced chemical clearance and mucosal integrity. By using the above described parameters, HRIM and MII/pH assays could be used to correctly classify RH and FH and hence allow physicians to provide adequate relief from associated symptoms.

Association between Laryngeal Pepsin Levels and the Presence of Vocal Fold Polyps.

Objective To determine whether pepsin, the main component of refluxed gastric contents, is significantly associated with vocal fold polyps and to evaluate the diagnostic value of pepsin in vocal fold polyps' tissues. Study Design Cross-sectional study. Setting Nanfang Hospital of Southern Medical University. Subjects and Methods The study included 32 patients with vocal fold polyps and 16 healthy controls between 2011 and 2012. Reflux symptom index and reflux finding score assessments, 24-hour combined multichannel intraluminal impedance and pH monitoring, and biopsy of the vocal fold polyp tissues or posterior laryngeal mucosa (healthy controls) for immunohistochemical pepsin staining were performed. Results The expression of pepsin was significantly higher in patients with vocal fold polyps than in controls (28/32, 75% vs 5/16, 31.25%; P < .001). The pepsin levels were significantly positively correlated with upright position pharyngeal acid reflux and esophageal reflux parameters adjusted by age. Based on pepsin staining data, the sensitivity and negative predictive values of 24-hour pH monitoring, the reflux symptom index, and the reflux finding score were 70% to 84.62%, whereas their specificity and positive predictive values were relatively low (20%-31.58%). Conclusion Pepsin reflux may be a risk factor for vocal fold polyps formation. In addition, pepsin immunohistochemical analysis of polyp biopsy samples appears to be a more sensitive and effective test for diagnosing laryngopharyngeal reflux than the reflux symptom index, the reflux finding score, and 24-hour pH monitoring in a clinical setting.

Laryngopharyngeal Reflux in Children with Chronic Otitis Media with Effusion.

Background/AimsTo evaluate the characteristic properties of laryngopharyngeal reflux (LPR) and gastroesophageal reflux (GER) in children with otitis media with effusion (OME) using 24-hour multichannel intraluminal impedance combined with dual-probe (pharyngeal and esophageal) pH-metry.MethodsChildren aged 7–10 years of age with OME underwent 24-hour multichannel intraluminal impedance pH-metry. The upper pH sensor was situated 1 cm above the upper esophageal sphincter, and the lower pH sensor was placed 3–5 cm above the lower esophageal sphincter. Parents were asked to complete the gastroesophageal reflux assessment of symptoms in a pediatrics questionnaire.ResultsTwenty-eight children were enrolled; LPR was detected in 19 (67.9%) children. The criteria of the LPR diagnosis was the presence of at least one supraesophageal episode with a pH < 5.0 and a change in the pH value measured from the initial level at the upper sensor of > 0.2. In total, 64 episodes were observed. Assessment of all LPR episodes showed the presence of 246 episodes in the entire study. A considerable predominance of weakly acidic episodes (87.8%) was noted; there were 6.5% acidic episodes, and weakly alkaline episodes reached 5.7%. Pathological GER was noted in 10 (35.7%) subjects. Acid GER was detected in 8 children, 2 of whom demonstrated non-acidic reflux. In the LPR-negative patients, no pathological GER was confirmed with the exception of a single case of non-acidic reflux.ConclusionsLPR was frequently noted in the group of children with OME, and it might be an important risk factor in this common disease.

Do Hiatal Hernias Influence GERD in Patients on PPI Therapy?

Introduction: 24-hour Multichannel intraluminal impedance and pH (MII-pH) esophageal monitoring allows detection of Gastro-esophageal reflux (GER). MII-PH allows identification of acid and non-acid reflux. Hiatal hernia (HH) is more common in Western countries. Complications of HH are frequent and are usually related to reflux. Aim: To evaluate the effect of the presence and size of HH on the GER characteristics assessed by MIIpH. Methods: Retrospective review of 119 consecutive adult patients on proton pump inhibitor (PPI) therapy who underwent an upper endoscopy and MII-pH studies (81 Females, mean age =52 years) between 2009 and 2014. Presence and size of HH was identified endoscopically. The group was divided based on the presence of HH and then subdivided based on the size of HH: small HH =2-3cm, medium HH=4-5cm and large HH ≥6cm. MII-pH reports were reviewed to assess GER characteristics. Results: 63/119 (52%) patients had HH. There was no statistically significant difference between the presence and size of HH and GER characteristics (tables). Conclusion: In patients on PPI therapy, HH does not seem to increase GERD as measured by MII-pH.Table 1: HH vs. no HHTable 2: Size of HH vs. no HH

Is the Impedance Baseline Helpful in the Evaluation of Globus Patients?

Background/AimsGastroesophageal reflux disease (GERD) has been suggested to be responsible for 23–68% of globus cases. The impedance baseline (IB) acquired by 24-hour multichannel intraluminal impedance monitoring has been proven to represent esophageal mucosal integrity. We aimed to investigate whether the IB is helpful for evaluating globus patients.MethodsTwenty-four-hour multichannel intraluminal impedance pH tracings (MII-pH) were evaluated in globus patients. Differences in the IB between the acid reflux, non-acid reflux, and no reflux groups were analyzed. Receiver operating characteristic (ROC) curves were obtained to determine the optimal measurement point from the lower esophageal sphincter (LES).ResultsA total of 62 patients were analyzed. MII-pH showed that acid reflux, non-acid reflux, and no reflux were present in 13, 5, and 44 patients, respectively. The acid reflux group had a significantly lower IB than the other groups at a location 3 cm from the LES. ROC curve analysis revealed that placement at a position 3 cm from the LES resulted in moderate diagnostic accuracy (area under the curve = 0.88). When we set 2500 Ω as the cut-off value for acid reflux at a position 3 cm from the LES, the additional diagnostic yield for acid reflux was increased by 19.4% compared with that obtained by MII-pH.ConclusionsIB is complementary to pH findings enabling identification of a subset of patients with co-existing acid reflux. Catheter placement at a location 3 cm from the LES and a cut-off value of 2500 Ω may be reasonable criteria for estimating acid reflux.

Normal values of 24-hour ambulatory esophageal impedance-pH monitoring in a rural South African cohort of healthy participants.

There are no data on 24-hour multichannel intraluminal impedance and pH monitoring in African populations. The purpose of this study was to provide the normal values of esophageal impedance and pH monitoring in a rural African populations. South African healthy rural participants were recruited and underwent 24 hours of esophageal impedance and pH monitoring. The median and the 95th percentiles of the total reflux episodes were 49 and 97, respectively, of which the corresponding number of acidic, weakly acidic, and weakly alkaline reflux were 15 and 55, 17 and 51, and 8 and 36, respectively. The compositions of the total reflux were 5 and 21 for liquid, 27 and 72 for mixed, and 10 and 39 for gas reflux, respectively. The median bolus clearance was 18 seconds and the median bolus exposure was 14 minutes/24 hours. The proximal extent was 6%. The 95th percent time of esophageal exposure to acid was 8.6 in 24 hours. Female and overweight participants were associated with an increased number of reflux events. There were more reflux episodes, and of which, more were weakly alkaline compared with previous similar studies. The findings provide reference values of gastroesophageal reflux for a South African rural population.

The prevalence of gastro-esophageal reflux disease and esophageal dysmotility in Chinese patients with idiopathic pulmonary fibrosis.

BackgroundThe cause of idiopathic pulmonary fibrosis (IPF) remains unknown, yet gastro-esophageal reflux disease (GERD) is highly prevalent in this population. GERD prevalence was studied, and esophageal function tests (EFT) were assessed in Chinese IPF patients.MethodsWe prospectively studied 69 IPF patients who undertook both stationary High Resolution esophageal Manometry/Impedance (HRiM) and 24-hour esophageal Multi-Channel Intraluminal Impedance with pH Recordings (MII/pH). Patients were divided into GERD+ and GERD- groups according to pH results. Controls were HRiM treated healthy volunteers, and patients without IPF received HRiM and MII/pH diagnosed with GERD.Results69 IPF patients, 62 healthy volunteers, and 88 IPF negative GERD patients were selected. GERD prevalence in IPF was 43/69 (62.3%), and 58.1% of patients presented with at least one typical symptom. Symptoms had a sensitivity of 58.1%, a specificity of 61.6%, a positive predictive value of 71.4% and a negative predictive of 47.1%. Compared with healthy volunteers, IPF patients had significantly decreased lower esophageal sphincter pressure (LESP), upper esophageal sphincter pressure (UESP) and complete bolus transit rate (CBTR). By contrast, IPF patients had increased total bolus transit time and prevalence of weak peristalsis. MII/pH showed that one third of IPF patients had abnormal distal and proximal reflux, especially non-acid reflux. Compared with GERD patients without IPF, GERD patients with IPF had significantly decreased CBTR and UESP with increased bolus exposure time.ConclusionsGERD prevalence in IPF was high, but symptoms alone were an unreliable predictor of reflux. IPF patients had lower LESP and UESP, impaired esophageal peristalsis and bolus clearance function with more proximal reflux events.

Comparisons of Esophageal Function Tests between Chinese and British Patients with Gastroesophageal Reflux Disease.

Objective. To investigate the esophageal function tests in British and Chinese patients with gastroesophageal reflux disease (GERD). Methods. Patients with GERD were selected from the functional gut clinic, London, and digestive department, Beijing Chao-Yang Hospital, after taking the examinations of High-resolution Manometry and Impedance (HRiM) and 24-hour Multi-Channel Intraluminal Impedance and pH Recording (MII/pH) between 2013 and 2014. Chinese healthy volunteers who undertook HRiM were also selected as control group. Results. Fifty-nine British and 82 Chinese patients with GERD and 62 Chinese healthy volunteers were entered. Values for British patients, Chinese patients, and healthy volunteers were as follows: Lower esophageal sphincter pressure (LESP) 16.0 ± 8.6, 16.5 ± 10.0, and 26.4 ± 10.9 mmHg, peristalsis (normal/small break/large break) 24/12/23, 44/10/28, and 57/1/4, total bolus transit time (TBTT) 7.3 ± 1.3, 7.6 ± 1.2, and 6.9 ± 0.9 s, and complete bolus transit rate (CBTR) 66.7 ± 37.8, 61.7 ± 36.4, and 90.3 ± 14.0%, respectively. Stepwise linear regression analysis showed that age, gender, and ethnicity did not have significant effect on LESP, TBTT, esophageal peristalsis, and CBTR in patients with GERD. Conclusions. British and Chinese patients with GERD presented similar values of LESP, TBTT, and impaired esophageal peristalsis and CBTR.

Tu1606 Hypopharyngeal Multichannel Intraluminal Impedance Improves the Outcome of Antireflux Surgery on Patients With Laryngeal Symptoms

Introduction: Patient selection is critical for the successful surgical treatment of gastroesophageal reflux disease (GERD). Previously, we established the normative data of laryngopharyngeal reflux (LPR) and high-esophageal reflux (HER: reflux up to 2cm distal to upper esophageal sphincter) events for 24-hour hypopharyngeal multichannel intraluminal impedance (HMII). Based on the data, we have constructed the criteria to define abnormal proximal exposure (APE) as LPR ≥1/day and/or HER ≥5/day. Previous retrospective analyses have suggested that HMII may increase the sensitivity in selecting patients with LPR symptoms who likely respond antireflux surgery (ARS). The purpose of this study was to objectively evaluate the outcome of ARS on patients selected based on our criteria by using validated questionnaires. Methods: This is a retrospective review of prospectively collected data from patients who underwent HMII. Patients with APE as measured by HMII and subsequently underwent ARS, were identified. The outcome of surgery included improvement in clinical symptoms and quality of life, both of which were assessed based on the personal interview and the validated questionnaires such as GERD-HRQL, Respiratory Symptom Index (RSI) and SF-36 before and after ARS. Results: From September 2012 to October 2013, 171 patients underwent HMII. Of 118 patients with APE, 26 patients underwent ARS (7 men and 19 women; mean age 51.6). Twenty-one patients (81%) had LPR symptoms including cough (n=20), throat burning (n=3), cervical dysphagia (n=3), throat tightness/pressure (n= 2), and hoarseness (n=1). Of 21 with LPR symptoms, 11 (42%) had concomitant typical GERD symptom such as heartburn and regurgitation. The mean DeMeester score was 15.7 (range 1-54.8) and 15 patients (58%) had negative DeMeester score. Clinical symptoms completely resolved in 20 patients (77%) and significantly improved in 5 patients (19%) at 6 weeks after the surgery. Anti-secretory medications were discontinued in 25 patients (96%) at a mean follow-up period of 2.1 months (0.36-5.3). Complete validated questionnaires before and after ARS were available for 11 patients. Of them, there was a significant improvement in GERD-HRQL (Pre-op 20.7; post-op 6.9, p= 0.016) and RSI scores (Pre-op 23.9; post-op 15, p=0.001) post-operatively. However, there was no significant difference in SF-36 scores on either physical component scores (pre-op 33.6; post-op 32.8, p=0.853) or mental component scores (pre-op 44.7; post-op 47.5, p=0.49). Conclusion: APE as measured by HMII, regardless of whether there is positive DeMeester score, may identify patients with laryngeal symptoms, who likely respond ARS, potentially improving the surgical outcome. Data set is currently being expanded and will be presented at the conference.

LPR: How Different Diagnostic Tools Shape the Outcomes of Treatment

To seek a deeper and more comprehensive understanding of two major diagnostic methods for laryngopharyngeal reflux by exploring whether and how differences exist before and after treatment between patients diagnosed by either Reflux Symptom Index (RSI) and Reflux Finding Score (RFS) or 24-hour pH monitoring. Two groups of patients who confirmed laryngopharyngeal reflux disease (LPRD) by either a combination of RSI and RFS (Questionnaire group, 35 patients) or 24-hour multichannel intraluminal impedance (MII) pH monitoring (pH Group, 23 patients) were recruited. All patients were prescribed esomeprazole 20 mg twice a day for 1month. RSI, RFS, and acoustic parameters before and after treatment were compared between the two groups. Intrinsic correlations involving multiple parameters were investigated as well. Except for excess throat mucus (P=0.019) and subglottic edema (P=0.042), most RSI and RFS items before treatment were not significantly different between the Questionnaire and pH Groups, and nearly all such items in both groups exhibited distinct remission after therapy (P<0.05). Absolute value of remission in RSI after treatment was more prominent in pH Group than in the Questionnaire group (P=0.007). Jitter (P=0.252), shimmer (P=0.815), and harmonics-to-noise ratio (P=0.117) descended to normal value after treatment. Moderate to high levels of correlation were found between the patient's original status and the absolute value of remission in most items of RSI and RFS as well as voice parameters. The 24-hour MII pH monitoring and a combination of RSI and RFS are quite competitive with each other in selecting LPRD patients. Although treatment worked out on nearly all the symptoms, laryngeal images and voice parameters, 24-hour MII pH seems to be more promising in a greater symptom relief. The extent of relief that can take place in most of the measurements is considerably determined by their initial status.

Tu1215 Weight Regain After Roux-en-Y Gastric Bypass Is Associated With Abnormal Non-Acid Reflux and Symptom-Association on 24-Hour pH-Impedance Monitoring

Background:Obesity has been associated with increased risk and severity of gastroesophageal reflux disease. Prior studies have shown that Roux-en-Y gastric bypass (RYGB) is effective for weight loss and can decrease reflux symptoms and esophagitis among obese patients. The mechanisms by which RYGB reduces reflux are not completely known. Post-RYGB patients may also develop reflux symptoms as a late complication of surgery. Weight regain (WR) has been shown to occur in 20% post-RYGB on long-term follow-up. No prior study has demonstrated the association between post-RYGB reflux symptoms and WR. Objective evaluation and understanding of post-RYGB reflux symptoms may also allow more effective, targeted therapy for these patients. Aim: To objectively evaluate reflux symptoms among post-RYGB patients using 24-hour multichannel intraluminal impedance and pH (MII-pH) study and investigate their association with WR. Methods: This was a retrospective cohort