ALBI score predicts morphological changes in esophageal varices following direct-acting antiviral-induced sustained virological response in patients with liver cirrhosis.

BACKGROUND: This study aimed to clarify the morphological changes in esophageal varices after achieving sustained virological response (SVR) with direct-acting antivirals (DAAs) in patients with cirrhosis. METHODS: A total of 243 patients underwent esophagogastroduodenoscopy before DAA treatment and after achieving SVR. Morphological changes in esophageal varices were investigated using esophagogastroduodenoscopy. RESULTS: This study comprised 125 males and 118 females with a median age of 68 years. Esophageal varices at baseline were classified into no varix in 155 (63.8%), F1 in 59 (24.3%), F2 in 25 (10.3%) and F3 in 4 (1.6%) patients. The improvement, unchanged, and aggravation rates of esophageal varices after SVR were 11.9%, 73.3%, and 14.8%, respectively. High ALBI score at SVR12 was an independent factor associated with post-SVR esophageal varices aggravation (p = 0.045). Time-dependent receiver operating characteristic (ROC) curve analysis revealed a cut-off value of - 2.33 for ALBI score at SVR12 in predicting post-SVR esophageal varices aggravation. Of the 155 patients without esophageal varices at baseline, 17 developed de novo post-SVR esophageal varices. High ALBI score at SVR12 was a significant independent factor associated with de novo post-SVR esophageal varices (p = 0.046). ROC curve analysis revealed a cut-off value of - 2.65 for ALBI score at SVR12 in predicting de novo post-SVR esophageal varices. CONCLUSIONS: Patients with cirrhosis can experience esophageal varices aggravation or de novo esophageal varices, despite achieving SVR. In particular, patients with high ALBI score at SVR12 have a high likelihood of developing post-SVR esophageal varices aggravation or de novo post-SVR esophageal varices.

Factors associated with prevalence and severity of erosive tooth wear in patients with reflux oesophagitis.

BACKGROUND: Extrinsic factors for erosive tooth wear (ETW) have been widely reported, but the intrinsic factors for wear remain unclear. OBJECTIVES: The aim of this study was to evaluate the factors associated with the prevalence of ETW in patients with reflux oesophagitis (RO). To prevent severe ETW with RO, factors associated with severity of ETW were also evaluated. METHODS: A total of 270 patients with RO were recruited. A modified tooth wear index was used to evaluate the prevalence and severity of ETW. Salivary secretion and buffering capacity were assessed prior to endoscopy. Subjects were asked to complete a medical condition and oral self-care questionnaire. Univariate and multivariate analyses were employed to identify factors collectively associated with the prevalence and severity of ETW. RESULTS: A total of 212 cases were categorized as patients with ETW (148 with mild ETW and 64 with severe ETW). Multivariate analyses indicated that saliva secretion, severity of RO and proton pump inhibitor (PPI) resistance were associated with the prevalence of ETW, whereas age, BMI and severity of RO were associated with the severity of ETW. The odds ratio of saliva secretion and BMI were less than 1, meaning that higher saliva secretion resulted in a lower prevalence of ETW and lower BMI was associated with severe ETW. CONCLUSION: Saliva secretion, severity of RO and PPI resistance were associated with the prevalence of ETW, whereas age, BMI and severity of RO were associated with the severity of ETW. Lower saliva secretion and BMI were significant factors for ETW.

Correction: Potential for expanded application of endoscopic hand suturing: A pilot study of 15 cases.

[This corrects the article DOI: 10.1055/a-2284-9492.].

Potential for expanded application of endoscopic hand suturing: A pilot study of 15 cases.

Endoscopic hand suturing (EHS) was first developed to firmly close a mucosal defect following endoscopic submucosal dissection and has the potential for expanded applications. This study aimed to investigate the feasibility and safety of EHS in various clinical settings. In this single-center pilot study, 15 patients who had diseases with potential indications for EHS were prospectively recruited. Technical success, clinical success after the procedure, and severe EHS-related adverse events (AEs) were evaluated. EHS was applied for defect closure after gastric subepithelial lesion removal under laparoscopic observation (n = 9), defect closure after rectal endoscopic full-thickness resection (EFTR) (n = 2), defect closure after thoracoscopy-assisted esophageal EFTR (n = 1), mucosal closure for gastric ulcer bleeding (n = 1), mucosal closure after peroral endoscopic myotomy (POEM) (n = 1), and postoperative anastomotic leak (n = 1). EHS was completed without severe AEs and the clinical courses were also favorable in 13 patients (87%). The median suturing time was 61 minutes. In patients with POEM and anastomotic leak, EHS was discontinued because of the narrow lumen. In conclusion, EHS appears feasible and safe in situations.

Tumor size discrepancy between endoscopic and pathological evaluations in colorectal endoscopic submucosal dissection.

BACKGROUND: Tumor size impacts the technical difficulty and histological curability of colorectal endoscopic submucosal dissection (ESD); however, the preoperative evaluation of tumor size is often different from histological assessment. Analyzing influential factors on failure to obtain an accurate tumor size evaluation could help prepare optimal conditions for safer and more reliable ESD. AIM: To investigate the tumor size discrepancy between endoscopic and pathological evaluations and the influencing factors. METHODS: This was a retrospective study conducted at a single institution. A total of 377 lesions removed by colorectal ESD at our hospital between April 2018 and March 2022 were collected. We first assessed the difference in size with an absolute percentage of the scaling discrepancy. Subsequently, we compared the clinicopathological characteristics of the correct scaling group (> -33% and < 33%) with that of the incorrect scaling group (< -33% or > 33%), which was further subdivided into the underscaling group (-33% or less of the discrepancy) and overscaling group (33% or more of the discrepancy), respectively. As secondary outcome measures, parameters on size estimation were compared between the underscaling and correct scaling groups, as well as between the overscaling and correct scaling groups. Finally, multivariate analysis was performed in terms of the following relevant parameters on size estimation: Pathological size, location, and possible influential factors (P < 0.1) in the univariate analysis. RESULTS: The mean of absolute percentage in the scaling discordance was 21%, and 91 lesions were considered to be incorrectly estimated in size. The incorrect scaling was significantly remarkable in larger lesions (40 mm vs 28 mm; P < 0.001) and less experience (P < 0.001), and these two factors were influential on the underscaling (75 lesions; P < 0.001). Conversely, compared with the correct scaling group, 16 lesions in the overscaling group were significantly small (20 mm vs 28 mm; P < 0.001), and the small lesion size was influential on the overscaling (P = 0.002). CONCLUSION: Lesions indicated for colorectal ESD tended to be underestimated in large tumors, but overestimated in small ones. This discrepancy appears worth understanding for optimal procedural preparation.

Impact of pemafibrate in patients with metabolic dysfunction-associated steatotic liver disease complicated by dyslipidemia: A single-arm prospective study.

Background and Aim: This study aimed to clarify the efficacy and safety of 48-week pemafibrate treatment in patients with metabolic dysfunction-associated steatotic liver disease (MASLD) complicated by dyslipidemia. Methods: A total of 110 patients diagnosed with MASLD complicated by dyslipidemia received pemafibrate at a dose of 0.1 mg twice daily for 48 weeks. Results: The participants were 54 males and 37 females, with a median age of 63 (52-71) years. Besides improvement in lipid profile, significant reductions from baseline to 48 weeks of treatment were found in liver-related enzymes, such as aspartate aminotransferase, alanine aminotransferase (ALT), gamma-glutamyl transpeptidase, and alkaline phosphatase (P < 0.001 for all). A significant decrease in the homeostasis model assessment-insulin resistance (HOMA-IR) was observed in patients with insulin resistance (HOMA-IR ≥ 2.5) (4.34 at baseline to 3.89 at Week 48, P < 0.05). Moreover, changes in ALT were weakly correlated with those in HOMA-IR (r = 0.34; p < 0.05). Regarding noninvasive liver fibrosis tests, platelets, Wisteria floribunda agglutinin-positive Mac-2-binding protein, type IV collagen 7s, and the non-alcoholic fatty liver disease fibrosis score significantly decreased from baseline to Week 48. Most adverse events were Grades 1-2, and no drug-related Grade 3 or higher adverse events were observed. Conclusion: This study demonstrated that 48-week pemafibrate administration improved liver-related enzymes and surrogate marker of liver fibrosis in patients with MASLD. The improvement of insulin resistance by pemafibrate may contribute to the favorable effect on MASLD complicated by dyslipidemia.

Kinetics of the hepatitis B core-related antigen and treatment responses in chronic hepatitis B patients treated with tenofovir alafenamide.

AIM: An association between hepatitis B core-related antigen (HBcrAg) kinetics and hepatocarcinogenesis during nucleoside (t)id analog (NA) treatment has recently been reported. HBcrAg kinetics and factors associated with HBcrAg response during tenofovir alafenamide (TAF) administration remain unclear. In this multicenter retrospective study, we aimed to clarify the efficacy and safety of TAF in treatment-naïve patients with chronic hepatitis B, focusing on the reduction in HBcrAg levels. METHODS: Patients were treated with TAF monotherapy for 96 weeks, and the kinetics of HBcrAg during treatment and the factors associated with HBcrAg response (defined as a change in HBcrAg of -1 log IU/mL from baseline) were evaluated. RESULTS: The study population comprised 241 patients, 36.9% of whom were HBeAg-positive. The median baseline HBcrAg level was 4.7 log IU/mL. The median change in HBcrAg from baseline was -1.1 log IU/mL at 96 weeks after treatment. The HBcrAg response rate at 96 weeks was 56.6% (43/76). Multivariate analysis revealed high alanine transaminase level as an independent baseline factor associated with HBcrAg response at 96 weeks of treatment (p = 4.53 × 10-6). No correlation was found between the HBcrAg and hepatitis B surface antigen kinetics in patients treated with TAF monotherapy. CONCLUSIONS: In TAF monotherapy for patients with chronic hepatitis B, HBcrAg levels were significantly decreased and baseline alanine transaminase level is an important factor associated with HBcrAg reduction. As no correlation was found between HBcrAg and reduced hepatitis B surface antigen levels in this study, HBcrAg kinetics in addition to hepatitis B surface antigen may need to be monitored during TAF treatment.

Low vitamin D levels accelerates muscle mass loss in patients with chronic liver disease.

Sarcopenia frequently and progressively occurs in patients with chronic liver disease. This study aimed to clarify the relationship between vitamin D levels and muscle mass loss. A total of 166 patients with chronic liver disease were enrolled in this study. Skeletal muscle mass index (SMI) was measured by bioelectrical impedance analysis at baseline and after 1 year. The rate of change in SMI from baseline after 1 year was calculated: ΔSMI (%) = [(1-year SMI - baseline SMI) / baseline SMI] × 100. Muscle mass loss was defined as ΔSMI ≤ -2%. The median 25-hydroxyvitamin D was 15.2 (11.2-19.3) ng/mL. The median SMI were 6.8 (5.9-7.8) kg/m2 at baseline and 6.7 (5.9-7.6) kg/m2 after 1 year. The median ΔSMI was -1.23% (-2.21% to 1.61%). Multivariate analysis identified low 25-hydroxyvitamin D as an independent factor associated with muscle mass loss. The optimal cut-off value of 25-hydroxyvitamin D to predict muscle mass loss was 12.7 ng/mL. Muscle mass loss was found in 56.4% v.s. 18.0% of patients with 25-hydroxyvitamin D < 12.7 vs. ≥ 12.7 ng/mL, respectively (p = 9.01 × 10-7); with the highest incidence in patients with non-alcoholic fatty liver disease (NAFLD). Specifically, patients with NAFLD and 25-hydroxyvitamin D < 12.7 ng/mL had a significantly higher incidence of muscle mass loss than those with ≥ 12.7 ng/mL (p = 1.23 × 10-3). Low vitamin D levels are associated with muscle mass loss after 1 year in patients with chronic liver disease, especially NAFLD.

In females, salivary secretion was significantly lower in patients with severe reflux esophagitis than in healthy controls.

BACKGROUND: The salivary secretion in patients with mild reflux esophagitis (RE) and non-erosive reflux disease is significantly lower in females, but not in males. However, sex differences in salivary secretion in patients with severe RE remain unknown. Therefore, the present study investigated sex differences in saliva secretion in patients with severe RE. METHODS: Subjects consisted of 23 male patients with severe RE, 24 male healthy controls (HCs), 26 female patients with severe RE, and 25 female HCs. Saliva secretion was assessed as follows: each patient chewed sugarless gum for 3 min prior to endoscopy, and the amount and pH of saliva secreted before and after acid loading as an index of the acid-buffering capacity were measured. RESULTS: In males, no significant differences were observed in the amount of saliva secretion, salivary pH, or the acid-buffering capacity between severe RE patients and HCs. In females, the amount of saliva secretion (severe RE: 2.4 [1.8-4.1], HCs: 5.3 [3.4-7.5], p = 0.0017), salivary pH (severe RE: 7.0 [6.7-7.3], HCs: 7.2 [7.1-7.3], p = 0.0455), and the acid-buffering capacity (severe RE: 5.9 [5.3-6.2], HCs: 6.2 [6.1-6.5], p = 0.0024) were significantly lower in severe RE patients than in HCs. CONCLUSION: Among females, the salivary secretion was significantly lower in severe RE patients than in HCs. This reduction in salivary secretion may contribute to the pathophysiology of severe RE in females.

Remarkable response as a new indicator for endoscopic evaluation of local efficacy of non-surgical treatments for esophageal cancer.

In Japan, standard of care of the patients with resectable esophageal cancer is neoadjuvant chemotherapy (NAC) followed by esophagectomy. Patients unfitted for surgery or with unresectable locally advanced esophageal cancer are generally indicated with definitive chemoradiotherapy (CRT). Local disease control is undoubtful important for the management of patients with esophageal cancer, therefore endoscopic evaluation of local efficacy after non-surgical treatments must be essential. The significant shrink of primary site after NAC has been reported as a good indicator of pathological good response as well as favorable survival outcome after esophagectomy. And patients who could achieve remarkable shrink to T1 level after CRT had favorable outcomes with salvage surgery and could be good candidates for salvage endoscopic treatments. Based on these data, "Japanese Classification of Esophageal Cancer, 12th edition" defined the new endoscopic criteria "remarkable response (RR)", that means significant volume reduction after treatment, with the subjective endoscopic evaluation are proposed. In addition, the finding of local recurrence (LR) at primary site after achieving a CR was also proposed in the latest edition of Japanese Classification of Esophageal Cancer. The findings of LR are also important for detecting candidates for salvage endoscopic treatments at an early timing during surveillance after CRT. The endoscopic evaluation would encourage us to make concrete decisions for further treatment indications, therefore physicians treating patients with esophageal cancer should be well-acquainted with each finding.

Potential of Direct Oral Anticoagulant in Bleeding After Gastric Endoscopic Submucosal Dissection: A Systematic Review and Meta-Analysis.

BACKGROUND AND AIMS: An increasing number of patients are undergoing gastric endoscopic submucosal dissection (ESD) with active prescriptions of direct oral anticoagulants (DOACs). Only a few reports have described the effects of DOAC intake on postoperative bleeding. We aimed to investigate the bleeding risk associated with DOACs after gastric ESD. METHODS: Clinical studies published up to April 2022 showing bleeding rates after gastric ESD in patients taking DOACs were identified using electronic searches. The primary outcome was the rate of bleeding after gastric ESD in patients receiving DOACs compared to those not receiving antithrombotic therapy. In this meta-analysis, odds ratios (ORs) were calculated and pooled using a random effects model. The secondary outcome was the difference in the bleeding rate between patients treated with DOACs and those treated with warfarin and antiplatelet drugs. RESULTS: Seven studies were included in this meta-analysis. The pooled analysis showed that DOACs had a higher bleeding rate than non-thrombotic therapy (17.0% vs. 3.4%; OR 5.72; 95% confidence interval [CI], 4.33-7.54; I2 = 0%). The bleeding risk associated with DOAC administration was similar to that associated with warfarin (17.0% vs. 20.0%; OR 0.83; 95% CI 0.59-1.18; I2 = 0%), whereas it was higher than that associated with antiplatelet administration (16.9% vs. 11.0%; OR 1.63; 95% CI 1.14-2.34; I2 = 8%). CONCLUSIONS: This meta-analysis reveals that the bleeding risk of DOACs is higher than that of non-antithrombotics and antiplatelets, whereas it is comparable to that of warfarin. Gastric ESD in patients on anticoagulants requires careful postoperative management.

Characteristics of proton pump inhibitor-resistant severe reflux esophagitis and efficacy of vonoprazan in elderly (older than 75 years) and non-elderly groups.

Background and Aim: Previous studies on age differences in proton pump inhibitor (PPI)-resistant reflux esophagitis (RE) have found that stenosis and bleeding complications were significantly more common in the elderly than in the non-elderly. We sought to examine differences between two groups of elderly (75 years or older) and non-elderly (<75 years) patients with (PPI)-resistant severe RE and also the efficacy of vonoprazan (VPZ) in these patients. Methods: There were 14 patients in the elderly group and 15 in the non-elderly group. Information was obtained on patient background (sex, body mass index [BMI], gastric mucosal atrophy, and the presence of hernia and collagen disease), and all patients underwent the saliva secretion test and esophagogastroduodenoscopy (EGD). The saliva secretion test (amount of saliva secreted, salivary pH, and the acid-buffering capacity) was performed by chewing sugar-free gum for 3 min before EGD. The efficacy of VPZ in both groups was also assessed. Results: Saliva secretion, sex, BMI, and the presence of gastric mucosal atrophy did not significantly differ between the two groups. The number of hernias larger than 4 cm was significantly higher in the elderly PPI-resistant group, and significantly more patients had collagen disease in the non-elderly group. The efficacy of VPZ was not significantly different between the two groups; however, 10 patients in the non-elderly group had collagen disease, and 4 did not achieve esophageal mucosal healing even with VPZ 20 mg. Conclusion: The number of large hernias (>4 cm) was significantly higher in the elderly group, while significantly more non-elderly patients had collagen disease. In the non-elderly group with scleroderma, the efficacy of VPZ 20 mg may not be sufficient.

Relationship Between Immunophenotypes, Genetic Profiles, and Clinicopathologic Characteristics in Small Bowel Adenocarcinoma.

Small bowel adenocarcinoma (SBA) is rare, and scant data exist regarding its molecular and clinicopathologic characteristics. This study aimed to clarify the correlation between immunophenotypes, DNA mismatch repair status, genomic profiling, and clinicopathologic characteristics in patients with SBA. We examined 68 surgical resections from patients with primary SBA for immunohistochemical analyses of CK7, CK20, CD10, CDX2, MUC1, MUC2, MUC4, MUC5AC, and MUC6 expression as well as mismatch repair status. Genomic profiling was performed on 30 cases using targeted next-generation sequencing. Tumor mucin phenotypes were classified as gastric, intestinal, gastrointestinal, or null based on MUC2, MUC5AC, MUC6, and CD10 immunostaining. The expression of these proteins was categorized into 3 classifications according to their relationship to: (1) tumor location: CK7/CK20, MUC4, and MUC6; (2) histologic type: mucinous adenocarcinoma was positive for MUC2 and negative for MUC6; and (3) TNM stage: CD10 was downregulated, whereas MUC1 was upregulated in advanced TNM stages. CDX2 was a specific marker for SBA generally expressed in the small intestine. MUC1 and MUC4 expression was significantly associated with worse prognosis. MUC2 expression correlated with better prognosis, except for mucinous adenocarcinoma. Although the difference was not statistically significant, gastric-type tumors were more frequently located in the duodenum and were absent in the ileum. APC and CTNNB1 mutations were not found in the gastric-type tumors. The SBA immunophenotype correlated with tumor location, biological behavior, and genomic alterations. Our results suggest that the molecular pathway involved in carcinogenesis of gastric-type SBA differs from that of intestinal-type SBA.

Patients with gastroesophageal reflux disease (both reflux oesophagitis and non-erosive reflux disease): Prevalence and severity of erosive tooth wear and saliva properties.

BACKGROUND: The prevalence between erosive tooth wear (ETW) in association with reflux oesophagitis (RO) has been reported. However, the severity of both diseases and the relationship between ETW and non-erosive reflux disease (NERD) is unclear. OBJECTIVES: The prevalence and severity of ETW were investigated in RO, NERD and healthy controls. METHODS: 135 patients with RO, 65 with NERD and 40 healthy controls were recruited for this case-control study. A modified tooth wear index was used to evaluate the prevalence and severity of ETW. Salivary secretion and buffer capacity were assessed prior to endoscopy. The prevalence and severity of ETW, saliva properties among each group were analysed using Pearson's chi-squared test. RESULTS: A total of 135 cases (56.3%) were categorised as the patient with ETW (55 with mild RO, 49 with severe RO and 31 with NERD). There was a significant relationship between the prevalence of RO and ETW, while there was no significant correlation between the prevalence of NERD and ETW. There was a significant difference related to the severity between RO and ETW. For salivary secretion, there was a significant difference between with and without ETW in patients with mild RO, severe RO and NERD. There was a significant difference between with and without ETW for salivary buffer capacity in patients with mild and severe RO. CONCLUSION: There was a significant association of the prevalence and severity between RO and ETW. Clinical signs such as ETW and salivary buffer capacity depended on the severity of RO.

Esophageal Motility Disorders: Diagnosis and Treatment Strategies.

BACKGROUND: Esophageal motility disorders (EMDs) are caused by the impaired relaxation of the upper/lower esophageal sphincter and/or defective esophageal peristaltic contractions, resulting in dysphagia and noncardiac chest pain. High-resolution manometry (HRM) is essential for the diagnosis of primary EMD; however, the recognition of EMD and HRM by general practitioners in Japan is limited. This review summarizes the diagnosis of and treatment strategies for EMD. SUMMARY: HRM is a specific test for the diagnosis of EMD, whereas endoscopy and barium swallow as screening tests provide characteristic findings (i.e., esophageal rosette and bird's beak sign) in some cases. It is important to note that manometric diagnoses apart from achalasia are often clinically irrelevant; therefore, the recently updated guidelines suggest additional manometric maneuvers, such as the rapid drink challenge, and further testing, including functional lumen imaging, for a more accurate diagnosis before invasive treatment. Endoscopic/surgical myotomy, pneumatic dilation, and botulinum toxin injections need to be considered for patients with achalasia and clinically relevant esophagogastric junction outflow obstruction. KEY MESSAGE: Since the detailed pathophysiology of EMD remains unclear, their diagnosis needs to be cautiously established prior to the initiation of invasive treatment.

Characteristics, outcomes, and risk factors of surgery for acute lower gastrointestinal bleeding: nationwide cohort study of 10,342 hematochezia cases.

BACKGROUND: Current evidence on the surgical rate, indication, procedure, risk factors, mortality, and postoperative rebleeding for acute lower gastrointestinal bleeding (ALGIB) is limited. METHODS: We constructed a retrospective cohort of 10,342 patients admitted for acute hematochezia at 49 hospitals (CODE BLUE J-Study) and evaluated clinical data on the surgeries performed. RESULTS: Surgery was performed in 1.3% (136/10342) of the cohort with high rates of colonoscopy (87.7%) and endoscopic hemostasis (26.7%). Indications for surgery included colonic diverticular bleeding (24%), colorectal cancer (22%), and small bowel bleeding (16%). Sixty-four percent of surgeries were for hemostasis for severe refractory bleeding. Postoperative rebleeding rates were 22% in patients with presumptive or obscure preoperative identification of the bleeding source and 12% in those with definitive identification. Thirty-day mortality rates were 1.5% and 0.8% in patients with and without surgery, respectively. Multivariate analysis showed that surgery-related risk factors were transfusion need ≥ 6 units (P < 0.001), in-hospital rebleeding (P < 0.001), small bowel bleeding (P < 0.001), colorectal cancer (P < 0.001), and hemorrhoids (P < 0.001). Endoscopic hemostasis was negatively associated with surgery (P = 0.003). For small bowel bleeding, the surgery rate was significantly lower in patients with endoscopic hemostasis as 2% compared to 12% without endoscopic hemostasis. CONCLUSIONS: Our cohort study elucidated the outcomes and risks of the surgery. Extensive exploration including the small bowel to identify the source of bleeding and endoscopic hemostasis may reduce unnecessary surgery and improve the management of ALGIB.

Among females older than 50 years, saliva secretion is significantly lower in non-erosive reflux disease patients than in healthy controls.

BACKGROUND: Saliva secretion is significantly lower in patients with non-erosive reflux disease (NERD) than in healthy controls (HC). A previous study on HC showed that saliva secretion was lower in females than in males. Saliva secretion may be lower in female patients with NERD than in male patients. Therefore, the present study investigated sex differences in saliva secretion in patients with NERD. METHODS: Subjects older than 50 years were included in the present study and consisted of 20 male patients with NERD, 19 male HC, 25 female patients with NERD, and 23 female HC. Saliva secretion was assessed as follows: each patient chewed sugar-free gum for 3 min prior to endoscopy, and the amount and pH of saliva before and after acid loading as an index of the acid-buffering capacity were measured. RESULTS: In males, no significant differences were observed in the amount of stimulated saliva secretion or salivary pH between NERD patients and HC. However, the acid-buffering capacity (NERD: 6.1 [5.9-6.5], HC: 6.4 [6.2-6.6]) was significantly lower in NERD patients than in HC. In females, the amount of stimulated saliva secretion (NERD: 2.6 [2.0-4.1], HC: 5.8 [3.7-7.5]), salivary pH (NERD: 7.0 [6.8-7.2], HC: 7.2 [7.0-7.2]), and the acid-buffering capacity (NERD: 5.8 [5.4-6.2], HC: 6.2 [6.0-6.5]) were significantly lower in NERD patients than in HC. CONCLUSION: Among females older than 50 years, saliva secretion was significantly lower in NERD patients than in HC. This reduction in saliva secretion may contribute to the pathophysiology of NERD in females.