title: Upper esophageal sphincter abnormalities: frequent finding on high-resolution esophageal manometry and associated with poorer treatment response in achalasia.
abstract: BACKGROUND
  Abnormalities of the upper esophageal sphincter (UES) on high-resolution esophageal manometry (HREM) have been observed in both symptomatic and asymptomatic individuals and are often interpreted as incidental findings of unclear clinical significance.
  
  
  OBJECTIVE
  Our primary aims were: (1) to assess the frequency of UES abnormalities in consecutive patients referred for HREM studies; and (2) to characterize the demographics, clinical symptoms, and manometric profiles associated with UES abnormalities as compared with those with normal UES function.
  
  
  METHODS
  We performed a retrospective study of 200 consecutive patients referred for HREM. Patients were divided into those with normal and abnormal UES function, including impaired relaxation (residual pressure >12 mm Hg), hypertensive (>104 mm Hg), and hypotensive (<34 mm Hg) resting pressure. Clinical and manometric profiles were compared.
  
  
  RESULTS
  A total of 32.5% of patients had UES abnormalities, the majority of which were hypertensive (55.4%). Patients with achalasia were significantly more likely to have UES abnormalities as compared with normal UES function (57.2% vs. 42.9%, P=0.04), with the most frequent abnormality being a hypertensive UES (50%). In addition, patients with impaired lower esophageal sphincter (LES) relaxation (esophagogastric junction outflow obstruction or achalasia) were more likely to have an UES abnormality present as compared with those with normal LES relaxation (53.1% vs. 28.6%, P=0.01). When we assessed for treatment response among patients with achalasia, we found that subjects with evidence of UES dysfunction had significantly worse treatment outcomes as compared with those without UES abnormalities present (20% improved vs. 100%, P=0.015). This remained true even after adjusting for type of treatment received (surgical myotomy, per-oral endoscopic mytotomy, botulinum toxin injection, pneumatic dilatation, medical therapy, P=0.67) and achalasia subtype (P=1.00).
  
  
  CONCLUSIONS
  UES abnormalities are a frequent finding on HREM studies, especially in patients with impaired LES relaxation, including both achalasia and esophagogastric junction outflow obstruction. Interestingly, the most common UES abnormality associated with achalasia was a hypertensive resting UES, despite the fact that achalasia is thought to spare striated muscle. Among patients with achalasia, we found a significant association between the lack of treatment response and the presence of UES dysfunction. The routine evaluation of UES function in patients referred for manometry may enhance our understanding of esophageal motility disorders and may yield important prognostic information, particularly in subjects with achalasia. Future prospective studies are needed to further delineate the underlying mechanism between UES dysfunction with achalasia and other esophageal motility disorders to predict treatment response and guide therapeutic treatment modalities.
authors.affiliation: *Department of Medicine ‡Division of Gastroenterology and Hepatology, Johns Hopkins University School of Medicine Baltimore, MD †Yale University School of Public Health, New Haven, CT.
authors.forename: Yamile H
authors.initials: YH
authors.lastname: Chavez
authors.forename: Maria M
authors.initials: MM
authors.lastname: Ciarleglio
authors.forename: John O
authors.initials: JO
authors.lastname: Clarke
authors.forename: Monica
authors.initials: M
authors.lastname: Nandwani
authors.forename: Ellen
authors.initials: E
authors.lastname: Stein
authors.forename: Bani C
authors.initials: BC
authors.lastname: Roland
mesh_terms: D000328:Adult; D000368:Aged; D004931:Esophageal Achalasia / Q000503:physiopathology* / Q000628:therapy*; D049630:Esophageal Sphincter, Lower / Q000503:physiopathology; D049631:Esophageal Sphincter, Upper / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry / Q000379:methods; D008875:Middle Aged; D011312:Pressure; D012189:Retrospective Studies; D016896:Treatment Outcome