title: The Chicago classification for achalasia in a French multicentric cohort.
abstract: BACKGROUND
  Achalasia is divided into 3 subtypes using the Chicago classification for high-resolution manometry. Aim of this study was to apply this classification to a multicentric French cohort of achalasia and to compare clinical and manometric characteristics between the 3 subtypes.
  
  
  METHODS
  Oesophageal symptoms were collected in a retrospective study of patients diagnosed with achalasia on high-resolution manometry. Manometry data were analyzed with oesophago-gastric junction resting and relaxation pressures, and upper oesophageal sphincter resting pressure. Achalasia was classified according to the Chicago classification.
  
  
  RESULTS
  From 2007 to August 2011, achalasia was diagnosed in 169 patients, 14% classified as type I, 70% as type II and 16% as type III. Type III patients were older than types I and II (62 years vs. 52, p = 0.03). Ninety five percent of patients complained of dysphagia, 16% of chest pain (no difference between the 3 subtypes); 50% of type I patients presented regurgitations compared to 33% of type II and 22% of type III (p = 0.10). Oesophago-gastric junction and upper oesophageal sphincter pressures did not differ between the 3 groups.
  
  
  CONCLUSIONS
  Type II was the more prevalent subtype of achalasia in this French multicentre cohort. The older age of patients with type III achalasia suggests a different pathophysiology.
authors.affiliation: Hospices Civils de Lyon, Edouard Herriot Hospital, Digestive Physiology, Lyon F-69437, France. roman.sabine@gmail.com
authors.forename: Sabine
authors.initials: S
authors.lastname: Roman
authors.forename: Frank
authors.initials: F
authors.lastname: Zerbib
authors.forename: Lucille
authors.initials: L
authors.lastname: Quenehervé
authors.forename: Hugo
authors.initials: H
authors.lastname: Clermidy
authors.forename: Stanislas Bruley des
authors.initials: SB
authors.lastname: Varannes
authors.forename: François
authors.initials: F
authors.lastname: Mion
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D015331:Cohort Studies; D003680:Deglutition Disorders / Q000209:etiology; D004931:Esophageal Achalasia / Q000145:classification* / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D049630:Esophageal Sphincter, Lower / Q000503:physiopathology; D004943:Esophagogastric Junction / Q000503:physiopathology; D005260:Female; D005602:France; D005764:Gastroesophageal Reflux / Q000209:etiology; D006801:Humans; D008297:Male; D008365:Manometry; D008875:Middle Aged; D012189:Retrospective Studies; D055815:Young Adult