Quality Indicator Development for the Approach to Ineffective Esophageal Motility: A Modified Delphi Study.

GOALS: Develop quality indicators for ineffective esophageal motility (IEM). BACKGROUND: IEM is identified in up to 20% of patients undergoing esophageal high-resolution manometry (HRM) based on the Chicago Classification. The clinical significance of this pattern is not established and management remains challenging. STUDY: Using RAND/University of California, Los Angeles Appropriateness Methods, we employed a modified-Delphi approach for quality indicator statement development. Quality indicators were proposed based on prior literature. Experts independently and blindly scored proposed quality statements on importance, scientific acceptability, usability, and feasibility in a 3-round iterative process. RESULTS: All 10 of the invited esophageal experts in the management of esophageal diseases invited to participate rated 12 proposed quality indicator statements. In round 1, 7 quality indicators were rated with mixed agreement, on the majority of categories. Statements were modified based on panel suggestion, modified further following round 2's virtual discussion, and in round 3 voting identified 2 quality indicators with comprehensive agreement, 4 with partial agreement, and 1 without any agreement. The panel agreed on the concept of determining if IEM is clinically relevant to the patient's presentation and managing gastroesophageal reflux disease rather than the IEM pattern; they disagreed in all 4 domains on the use of promotility agents in IEM; and had mixed agreement on the value of a finding of IEM during anti-reflux surgical planning. CONCLUSION: Using a robust methodology, 2 IEM quality indicators were identified. These quality indicators can track performance when physicians identify this manometric pattern on HRM. This study further highlights the challenges met with IEM and the need for additional research to better understand the clinical importance of this manometric pattern.

A Delphi Method for Development of a Barrett's Esophagus Question Prompt List as a Communication Tool for Optimal Patient-physician Communication.

BACKGROUND METHODS: The question prompt list content was derived through a modified Delphi process consisting of 3 rounds. In round 1, experts provided 5 answers to the prompts "What general questions should patients ask when given a new diagnosis of Barrett's esophagus" and "What questions do I not hear patients asking, but given my expertise, I believe they should be asking?" Questions were reviewed and categorized into themes. In round 2, experts rated questions on a 5-point Likert scale. In round 3, experts rerated questions modified or reduced after the previous rounds. Only questions rated as "essential" or "important" were included in Barrett's esophagus question prompt list (BE-QPL). To improve usability, questions were reduced to minimize redundancy and simplified to use language at an eighth-grade level (Fig. 1). RESULTS: Twenty-one esophageal medical and surgical experts participated in both rounds (91% males; median age 52 years). The expert panel comprised of 33% esophagologists, 24% foregut surgeons, and 24% advanced endoscopists, with a median of 15 years in clinical practice. Most (81%), worked in an academic tertiary referral hospital. In this 3-round Delphi technique, 220 questions were proposed in round 1, 122 (55.5%) were accepted into the BE-QPL and reduced down to 76 questions (round 2), and 67 questions (round 3). These 67 questions reached a Flesch Reading Ease of 68.8, interpreted as easily understood by 13 to 15 years olds. CONCLUSIONS: With multidisciplinary input, we have developed a physician-derived BE-QPL to optimize patient-physician communication. Future directions will seek patient feedback to distill the questions further to a smaller number and then assess their usability.

Esophageal Lichen Planus: A Descriptive Multicenter Report.

GOALS: To better understand the characteristics, treatment approaches, and outcomes of patients with esophageal lichen planus (ELP). BACKGROUND: ELP is a rare, often unrecognized and misdiagnosed disorder. Data on this unique patient population are currently limited to small, single-center series. STUDY: A multicenter, retrospective descriptive study was conducted of adults diagnosed with ELP over a 5-year period, between January 1, 2015, and October 10, 2020, from 7 centers across the United States. RESULTS: Seventy-eight patients (average age 65 y, 86% female, 90% Caucasian) were included. Over half had at least 1 extraesophageal manifestation. Esophageal strictures (54%) and abnormal mucosa (50%) were frequent endoscopic findings, with the proximal esophagus the most common site of stricture. Approximately 20% had normal endoscopic findings. Topical steroids (64%) and/or proton pump inhibitors (74%) dominated management; endoscopic response favored steroids (43% vs. 29% respectively). Almost half of the patients required switching treatment modalities during the study period. Adjunctive therapies varied significantly between centers. CONCLUSIONS: Given its at times subtle clinical and endoscopic signs, a high index of suspicion and biopsy will improve ELP diagnosis, especially in those with extraesophageal manifestations. Effective therapies are lacking and vary significantly. Prospective investigations into optimal treatment regimens are necessary.

Esophageal Function Testing Patterns in the Evaluation and Management of Lung Transplantation: Results of a National Survey.

GOALS: We surveyed esophageal motility laboratories affiliated with adult pulmonary transplant centers to determine esophageal function testing (EFT) practices. BACKGROUND: Gastroesophageal reflux and esophageal dysmotility are associated with worse lung transplant outcomes, yet no consensus guidelines for EFT exist in this population. STUDY: A deidentified online survey was sent to gastrointestinal motility laboratory directors of 49 academic and community-affiliated medical centers that perform lung transplants. Practice characteristics, including annual lung transplant volume and institutional EFT practices pre-lung transplantation and post-lung transplantation were queried. Respondents were categorized by transplant volume into small and large programs based on median annual volume. RESULTS: Among 35 respondents (71% response rate), the median annual transplant volume was 37, and there were 18 large programs. Institutional EFT protocols were used pretransplant by 24 programs (68.6%) and post-transplant by 12 programs (34.2%). Among small and large programs, 52.9% and 72.2% always obtained high-resolution manometry before transplant, respectively. Endoscopy before transplant was performed more often in small programs (n=17, 100%) compared with large programs (n=15,83.3%). Pretransplant endoscopy ( P =0.04), barium esophagram ( P <0.01), and high-resolution manometry ( P =0.04) were more common than post-transplant. In contrast, post-transplant reflux monitoring off-therapy was more common than pretransplant ( P =0.01). In general, pulmonologists direct referrals for EFT and gastroenterology consultation (n=28, 80.0%), with symptoms primarily prompting testing. CONCLUSIONS: In the absence of established guidelines, substantial variability exists in pretransplant and post-transplant EFT, directed by pulmonologists. Standardized EFT protocols and gastroenterologist-directed management of esophageal dysfunction has potential to improve lung transplant outcomes.

Development and Validation of a Machine Learning System to Identify Reflux Events in Esophageal 24-Hour pH/Impedance Studies.

INTRODUCTION: Esophageal 24-hour pH/impedance testing is routinely performed to diagnose gastroesophageal reflux disease. Interpretation of these studies is time-intensive for expert physicians and has high inter-reader variability. There are no commercially available machine learning tools to assist with automated identification of reflux events in these studies. METHODS: A machine learning system to identify reflux events in 24-hour pH/impedance studies was developed, which included an initial signal processing step and a machine learning model. Gold-standard reflux events were defined by a group of expert physicians. Performance metrics were computed to compare the machine learning system, current automated detection software (Reflux Reader v6.1), and an expert physician reader. RESULTS: The study cohort included 45 patients (20/5/20 patients in the training/validation/test sets, respectively). The mean age was 51 (standard deviation 14.5) years, 47% of patients were male, and 78% of studies were performed off proton-pump inhibitor. Comparing the machine learning system vs current automated software vs expert physician reader, area under the curve was 0.87 (95% confidence interval [CI] 0.85-0.89) vs 0.40 (95% CI 0.37-0.42) vs 0.83 (95% CI 0.81-0.86), respectively; sensitivity was 68.7% vs 61.1% vs 79.4%, respectively; and specificity was 80.8% vs 18.6% vs 87.3%, respectively. DISCUSSION: We trained and validated a novel machine learning system to successfully identify reflux events in 24-hour pH/impedance studies. Our model performance was superior to that of existing software and comparable to that of a human reader. Machine learning tools could significantly improve automated interpretation of pH/impedance studies.

Development and modification of a dysphagia question prompt list to improve patient-physician communication: Incorporating both esophageal expert and patient perspectives.

BACKGROUND: Question prompt lists (QPLs) are structured sets of disease-specific questions, intended to encourage question-asking by patients and enhance patient-physician communication. To date, a dysphagia-specific QPL has not been developed for patients with esophageal dysphagia symptoms. We aim to develop a dysphagia-specific QPL incorporating both esophageal expert and patient perspectives, applying rigorous methodology. METHODS: The QPL content was generated applying a two-round modified Delphi (RAND/UCLA) method among 11 experts. In round one, experts provided five answers to the prompts: "What general questions should patients ask when being seen for dysphagia?" and "What questions do I not hear patients asking but, given my experience, I believe they should be asking?" In round two, experts rated proposed questions on a 5-point Likert scale. Responses rated as "essential" or "important", determined by an a priori median threshold of ≥4.0, were accepted for inclusion. Subsequently, 20 patients from Stanford Health Care were enrolled to modify the preliminary QPL, to incorporate their perspectives and opinions. Patients independently rated questions applying the same 5-point Likert scale. At the end, patients were encouraged to propose additional questions to incorporate into the QPL by open-endedly asking "Are there questions we didn't ask, that you think we should?" KEY RESULTS: Eleven experts participated in both voting rounds. Of 85 questions generated from round one, 60 (70.6%) were accepted for inclusion, meeting a median value of ≥4.0. Questions were combined to reduce redundancy, narrowing down to 44 questions. Questions were categorized into the following six themes: 1. "What is causing my dysphagia?"; 2. "Associated symptoms"; 3. "Testing for dysphagia"; 4. "Lifestyle modifications"; 5. "Treatment for dysphagia"; and 6. "Prognosis". The largest number of questions covered "What is causing my dysphagia" (27.3%). Twenty patients participated and modified the QPL. Of the 44 questions experts agreed were important, only 30 questions (68.2%) were accepted for inclusion. Six patients proposed 10 additional questions and after incorporating the suggested questions, the final dysphagia-specific QPL created by esophageal experts and modified by patients consisted of 40 questions. CONCLUSIONS & INFERENCES: Incorporating expert and patient perspectives, we developed a dysphagia-specific QPL to enhance patient-physician communication. Our study highlights importance of incorporating patient perspective when developing such a communication tool. Further studies will measure the impact of this communication tool on patient engagement.

The Impact of Intermittent Fasting on Patients With Suspected Gastroesophageal Reflux Disease.

GOAL: The aim was to investigate the short-term impact of time restricted feeding on patients with suspected gastroesophageal reflux disease (GERD). BACKGROUND: Lifestyle modifications are often suggested, but the role of diet in GERD is unclear. Intermittent fasting is popular in the media and has demonstrated potential benefits with weight loss and inflammatory conditions as well as alterations in gastrointestinal hormones. STUDY: Patients who were referred for 96-hour ambulatory wireless pH monitoring off proton pump inhibitor to investigate GERD symptoms were screened for eligibility. Patients were instructed to maintain their baseline diet for the first 2 days of pH monitoring and switch to an intermittent fasting regimen (16 consecutive hour fast and 8 h eating window) for the second 2 days. Objective measures of reflux and GERD symptom severity were collected and analyzed. RESULTS: A total of 25 participants were analyzed. 9/25 (36%) fully adhered to the intermittent fasting regimen, with 21/25 (84%) demonstrating at least partial compliance. Mean acid exposure time on fasting days was 3.5% versus 4.3% on nonfasting days. Intermittent fasting was associated with a 0.64 reduction in acid exposure time (95% CI: -2.32, 1.05). There was a reduction in GERD symptom scores of heartburn and regurgitation during periods of intermittent fasting (14.3 vs. 9.9; difference of -4.46, 95% CI: -7.6,-1.32). CONCLUSIONS: Initial adherence to time restricted eating may be difficult for patients. There is weak statistical evidence to suggest that intermittent fasting mildly reduces acid exposure. Our data show that short-term intermittent fasting improves symptoms of both regurgitation and heartburn.

Nutrient Drink Test to Assess Gastric Accommodation in Cyclic Vomiting Syndrome: Single-blinded Parallel Grouped Prospective Study.

Background/Aims: Cyclic vomiting syndrome (CVS) is characterized by episodes of nausea and vomiting, separated by symptom-free intervals. The pathogenesis of CVS is poorly understood. Limited data exist on evaluating impaired gastric accommodation as a mechanistic means for symptoms. We aim to determine if CVS patients demonstrate impaired gastric accommodation applying a nutrient drink test (NDT) protocol. Methods: Through this single-blinded pilot clinical trial, patients with CVS per Rome IV critera and healthy controls were assessed for presence of impaired gastric accommodation by administering an established NDT protocol. Statistical analysis was performed, with data presented as medians and interquartile range. Results: Eleven CVS patients and 15 healthy controls participated in the study between January 2018 and October 2018. Median age was 42.0 years and 37.0 years; majority of subjects were female, 72.7% and 73.3%, respectively. Demographics were similar between CVS and healthy controls. Almost all healthy controls (93.3%) ingested the complete 500 mL protocol, whereas a smaller proportion (72.7%) were able to complete all 4 doses in the CVS group (P = 0.188). Post-prandial visual analogue scale scores of nausea and abdominal pain were found to be significantly higher in CVS patients compared to healthy controls. Conclusions: To our knowledge, this is the first NDT protocol in CVS evaluating the role of impaired gastric accommodation and hypersensitivity as a possible pathophysiologic mechanism. Findings from this study suggest the presence of gastric hypersensitivity in a subset of CVS patients. These results provide the foundational data necessary for future larger testing of NDT and diagnostic accuracy in CVS.

Quality Indicators for the Diagnosis and Management of Eosinophilic Esophagitis.

INTRODUCTION: Despite best practice recommendations for managing eosinophilic esophagitis (EoE), variation in care exists. METHODS: We used established methodology for quality indicator development to identify metrics to define quality for the treatment of EoE. RESULTS: Among 29 proposed quality indicator statements, 9 (31%) were adopted as highly valid across all categories. Two (22%) of these statements were identified as having existing or suspected quality gaps. DISCUSSION: We identified highly valid EoE quality indicators for adult gastroenterologists, which can be used for quality improvement with resulting benefits for patient outcomes.

Value of 96-hour ambulatory esophageal pH monitoring in the assessment of patients with refractory acid reflux symptoms and their response to anti-reflux diet.

Ambulatory esophageal pH monitoring is a diagnostic tool in patients with heartburn and regurgitation. The aim of this study is to evaluate 96-hour esophageal pH monitoring in patients with gastroesophageal reflux disease (GERD), at baseline and under diet that impedes GER. We hypothesized that diet would potentially reduce pathologic acid exposure time (AET). Retrospective series of 88 patients with GERD undergoing wireless 96-hour pH monitoring. Two-day (48 hours) tandem periods, one on liberal, followed by another on restricted diet assessed esophageal AET. Primary end point was >30% reduction in AET while on anti-GER diet. Of the 88 patients, 16 were excluded because of probe migration. Endoscopy and biopsies assessed erosive esophagitis (EE) and Barrett's esophagus (BE), or normal esophagus. Abnormal AET (% pH < 4.0 ≥ 6) further defined nonerosive reflux disease (NERD), whereas normal AET (% pH < 4.0 < 6) with normal endoscopy defined patients as functional heartburn (FH). There were 6 patients with EE (n = 5) and BE (n = 1), 23 with NERD and 43 with FH. Anti-GER diet led to >30% reduction in AET in EE and NERD patients, but not in those with FH. Most patients (n = 43/72; 60%) had FH and could have avoided acid suppression. Furthermore, (14/23; 61%) of patients with NERD completely normalized AET with diet, potentially negating acid suppression. Ninety-six-hour esophageal pH distinguishes GERD patients from those with FH. Fifty percent of EE/BE patients and 61% of those with NERD completely normalize AET with diet. If pathologic AET occurs despite diet, acid suppression is indicated.

Achalasia Quality Indicator Adherence.

BACKGROUND: Quality indicators (QIs) are formal ways to track health care performance and outcomes, guide quality improvement, and identify gaps in care delivery. We developed twelve quality indicators for achalasia management which cover the domains of patient education, diagnosis, and treatment of achalasia. AIM: To determine adherence to established quality indicators for achalasia management. METHODS: We performed a retrospective, multicenter evaluation of care patterns for adult patients greater than 18 years old with newly diagnosed achalasia from January 2018 to May 2020. A balanced random patient sample was obtained at four large academic medical centers. Independent electronic health record chart abstraction was performed using a standardized form to determine adherence to applicable QIs. Pooled and de-identified data were analyzed to identify gaps in care. RESULTS: A total of 120 patients were included and the overall adherence to applicable quality indicators across all centers was 86%. The median follow-up for all patients from time of diagnosis to end of study was 511 days. Clinicians adhered to all applicable quality indicators in 49 patients (39%). The quality indicator domain with the poorest adherence was patient education (67%), with 50% of patients having had a documented discussion of the risks of gastroesophageal reflux disease following surgical or endoscopic myotomy. CONCLUSIONS: Gaps in the quality of achalasia care delivery were identified, the largest of which relates to patient education about treatment risks. These findings highlight a potential area for future quality improvement studies and form the basis for developing fully specified quality measures.

Development of a Preliminary Question Prompt List as a Communication Tool for Adults With Achalasia: A Modified Delphi Study.

BACKGROUND: Question prompt lists (QPLs) are structured sets of disease-specific questions that enhance patient-physician communication by encouraging patients to ask questions during consultations. AIM: The aim of this study was to develop a preliminary achalasia-specific QPL created by esophageal experts. METHODS: The QPL content was derived through a modified Delphi method consisting of 2 rounds. In round 1, experts provided 5 answers to the prompts "What general questions should patients ask when given a new diagnosis of achalasia" and "What questions do I not hear patients asking, but given my expertise, I believe they should be asking?" In round 2, experts rated questions on a 5-point Likert scale. Questions considered "essential" or "important" were accepted into the QPL. Feedback regarding the QPL was obtained in a pilot study wherein patients received the QPL before their consultation and completed surveys afterwards. RESULTS: Nineteen esophageal experts participated in both rounds. Of 148 questions from round 1, 124 (83.8%) were accepted into the QPL. These were further reduced to 56 questions to minimize redundancy. Questions were categorized into 6 themes: "What is achalasia," "Risks with achalasia," "Symptom management in achalasia," "Treatment of achalasia," "Risk of reflux after treatment," and "Follow-up after treatment." Nineteen patients participated in the pilot, most of whom agreed that the QPL was helpful (84.2%) and recommended its wider use (84.2%). CONCLUSIONS: This is the first QPL developed specifically for adults with achalasia. Although well-received in a small pilot, follow-up studies will incorporate additional patient feedback to further refine the QPL content and assess its usability, acceptability, and feasibility.

Best Practices in Treatment of Laryngopharyngeal Reflux Disease: A Multidisciplinary Modified Delphi Study.

BACKGROUND: Laryngopharyngeal reflux (LPR) is a common otolaryngologic diagnosis. Treatment of presumed LPR remains challenging, and limited frameworks exist to guide treatment. METHODS: Using RAND/University of California, Los Angeles (UCLA) Appropriateness Methods, a modified Delphi approach identified consensus statements to guide LPR treatment. Experts independently and blindly scored proposed statements on importance, scientific acceptability, usability, and feasibility in a four-round iterative process. Accepted measures reached scores with ≥ 80% agreement in the 7-9 range (on a 9-point Likert scale) across all four categories. RESULTS: Fifteen experts rated 36 proposed initial statements. In round one, 10 (27.8%) statements were rated as valid. In round two, 8 statements were modified based on panel suggestions, and experts subsequently rated 5 of these statements as valid. Round three's discussion refined statements not yet accepted, and in round four, additional voting identified 2 additional statements as valid. In total, 17 (47.2%) best practice statements reached consensus, touching on topics as varied as role of empiric treatment, medication use, lifestyle modifications, and indications for laryngoscopy. CONCLUSION: Using a well-tested methodology, best practice statements in the treatment of LPR were identified. The statements serve to guide physicians on LPR treatment considerations.

Intra-subject Variability in High Resolution Anorectal Manometry Using the London Classification: Diagnostic and Therapeutic Implications.

This retrospective pilot study conducted on a community-based cohort of both men and women of various ages and underlying clinical presentations examined the durability and reproducibility of HR-ARM findings influencing their potential impact on clinical decision-making at the point of care (Jameson et al. in Br J Surg 81:1689-1692, 1994). The key finding of our study was that only a minority of patients who underwent repeat anorectal manometry as analyzed by the London Classification had stable manometric findings, raising questions regarding the validity of a single manometric measurement, as currently analyzed, for clinical decision-making.

Question Prompt List as a Communication Tool for Adults With Gastroesophageal Reflux Disease: Incorporation of Patients' Perspectives.

BACKGROUND: Question prompt lists (QPLs) are structured sets of disease-specific questions intended for patient use, enhancing the patient-physician communication by encouraging patients to ask relevant questions during a consultation. Recently, a preliminary 78 question gastroesophageal reflux disease (GERD) specific QPL was created by 12 esophageal experts through a modified Delphi (RAND/University of California, Los Angeles) technique. Patients' perspectives and opinions on each question, however, had not been accounted for in the preliminary expert' version. AIM: The aim was to modify a preliminary experts' QPL, specific to adults with GERD, following patient perspectives and opinions. METHODS: A preliminary GERD QPL was modified through patient input and opinions. Thirty-eight patients with a clinical diagnosis of GERD followed at Stanford University Esophageal Clinic between January and November 2019 were consented to modify the preliminary 78 question expert QPL version. After receiving the QPL in Qualtrics (Provo, UT) by a direct e-mail invitation, patients independently rated questions on a 5-point Likert scale, where 1="should not be included," 2="unimportant," 3="don't know/depends," 4="important," and 5="essential." Questions were accepted for inclusion in the QPL with an a priori interagreement of 80% ranking in the range of 4 to 5. At the end, patients were encouraged to propose additional questions to incorporate into the QPL by open-endedly asking "Are there questions we didn't ask, that you think we should?" RESULTS: Twenty-three patients with GERD (19 female, median age 64) fully participated and modified the existing QPL (60.5%). Of the 78 questions from the preliminary GERD QPL, 66 questions (84.6%) were accepted for inclusion. The question with the highest agreement among patients rating a question as essential consisted of "what habits, food, and drinks do I have to avoid?" (82.6%). Questions eliminated because of disagreement included "What is the natural history of GERD," "Do I have a high chance to die from my Barrett's?," and "Why are you prescribing an antidepressant to treat my GERD?" Nine patients suggested additional questions totaling to 16 separate questions, including "What type of surgeries are there to help GERD?," "What stage is my GERD?," "What are the odds/percentage of getting cancer from GERD?" Incorporating the suggested questions, the final GERD QPL-created by esophageal experts and modified by patients-consisted of 82 questions. CONCLUSION: Esophageal experts and GERD patients have a high level of agreement on important questions, though there is some variation in perspective. Future studies can simplify this list and measure the impact of a shared GERD QPL on patients' decisional conflict and perceived involvement in care.

Development of quality indicators for the diagnosis and management of achalasia.

BACKGROUND: The management of achalasia has improved due to diagnostic and therapeutic innovations. However, variability in care delivery remains and no established measures defining quality of care for this population exist. We aimed to use formal methodology to establish quality indicators for achalasia patients. METHODS: Quality indicator concepts were identified from the literature, consensus guidelines and clinical experts. Using RAND/University of California, Los Angeles (UCLA) Appropriateness Method, experts in achalasia independently ranked proposed concepts in a two-round modified Delphi process based on 1) importance, 2) scientific acceptability, 3) usability, and 4) feasibility. Highly valid measures required strict agreement (≧ 80% of panelists) in the range of 7-9 for across all four categories. KEY RESULTS: There were 17 experts who rated 26 proposed quality indicator topics. In round one, 2 (8%) quality measures were rated valid. In round two, 19 measures were modified based on panel suggestions, and experts rated 10 (53%) of these measures as valid, resulting in a total of 12 quality indicators. Two measures pertained to patient education and five to diagnosis, including discussing treatment options with risk and benefits and using the most recent version of the Chicago Classification to define achalasia phenotypes, respectively. Other indicators pertained to treatment options, such as the use of botulinum toxin for those not considered surgical candidates and management of reflux following achalasia treatment. CONCLUSIONS & INFERENCES: Using a robust methodology, achalasia quality indicators were identified, which can form the basis for establishing quality gaps and generating fully specified quality measures.

Type II Achalasia Is Increasing in Prevalence.

BACKGROUND: Three manometric subtypes of achalasia were defined in the Chicago Classification approximately 10 years ago: type I (aperistalsis), type II (pan-pressurization), and type III (spastic). Since the widespread use of this classification scheme, the evolving prevalence of these subtypes has not been elucidated. We aim to determine the prevalence of each subtype a decade after the adoption of the Chicago Classification. METHODS: This is a retrospective cohort analysis of patients diagnosed with achalasia on high-resolution manometry (HRM) at two major academic medical centers between 2015 and 2018. Patients were excluded if they had a diagnosis of another esophageal motility disorder, previously treated achalasia, or foregut surgery. Demographic data, manometric subtype, and esophageal dilatation grade on endoscopy were obtained. Prevalence of achalasia subtypes was compared with a published historical control population (2004-2007). Fischer's exact and t tests were used for analysis. RESULTS: Of 147 patients in the contemporary cohort and 99 in the historical control cohort, the prevalence of type I achalasia was 8% versus 21%, type II 63% versus 50%, and type III 29% versus 29%, respectively (p = 0.01). The mean age in our population was 58 years compared to 57 years in the historical control, and the proportion of men 48% versus 47%, respectively (p = 0.78). Mean endoscopic dilatation grade in the contemporary cohort was 1.5 for type I patients, 0.9 for type II, and 0.4 for type III, compared with 1.5, 0.6, and 0.4, respectively. Overall mean dilatation grade was 0.8 in our cohort versus 0.7 in the historical control (p = 0.58). CONCLUSION: The prevalence of type II achalasia was significantly greater and prevalence of type I significantly less in our patient population compared to our predefined historical control. Other characteristics such as age and sex did not appear to contribute to these differences. Histopathological evidence has suggested that type II achalasia may be an earlier form of type I; thus, the increased prevalence of type II achalasia may be related to earlier detection of the disease. The adoption of HRM, widespread use of the Chicago Classification, and increased disease awareness in the past decade may be contributing to these changes in epidemiology.