title: Ineffective oesophageal motility: manometric subsets exhibit different symptom profiles.
abstract: OBJECTIVE
  To compare the demographic and clinical features of different manometric subsets of ineffective oesophageal motility (IOM; defined as > or = 30% wet swallows with distal contractile amplitude < 30 mmHg), and to determine whether the prevalence of gastro-oesophageal reflux differs between IOM subsets.
  
  
  METHODS
  Clinical characteristics of manometric subsets were determined in 100 IOM patients (73 female, median age 58 years) and compared to those of 100 age-and gender-matched patient controls with oesophageal symptoms, but normal manometry. Supine oesophageal manometry was performed with an eight-channel DentSleeve water-perfused catheter, and an ambulatory pH study assessed gastro-oesophageal reflux.
  
  
  RESULTS
  Patients in the IOM subset featuring a majority of low-amplitude simultaneous contractions (LASC) experienced less heartburn (prevalence 26%), but more dysphagia (57%) than those in the IOM subset featuring low-amplitude propagated contractions (LAP; heartburn 70%, dysphagia 24%; both P < or = 0.01). LASC patients also experienced less heartburn and more dysphagia than patient controls (heartburn 68%, dysphagia 11%; both P < 0.001). The prevalence of heartburn and dysphagia in IOM patients featuring a majority of non-transmitted sequences (NT) was 54% (P = 0.04 vs LASC) and 36% (P < 0.01 vs controls), respectively. No differences in age and gender distribution, chest pain prevalence, acid exposure time (AET) and symptom/reflux association existed between IOM subsets, or between subsets and controls.
  
  
  CONCLUSIONS
  IOM patients with LASC exhibit a different symptom profile to those with LAP, but do not differ in gastro-oesophageal reflux prevalence. These findings raise the possibility of different pathophysiological mechanisms in IOM subsets, which warrants further investigation.
authors.affiliation: Department of Gastroenterology, Gastrointestinal Investigation Unit, Royal North Shore Hospital, University of Sydney, Australia.
authors.forename: Horst-Gunter
authors.initials: HG
authors.lastname: Haack
authors.forename: Ross-David
authors.initials: RD
authors.lastname: Hansen
authors.forename: Allison
authors.initials: A
authors.lastname: Malcolm
authors.forename: John-Edward
authors.initials: JE
authors.lastname: Kellow
mesh_terms: D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D016022:Case-Control Studies; D002637:Chest Pain / Q000209:etiology / Q000503:physiopathology; D003679:Deglutition; D003680:Deglutition Disorders / Q000209:etiology / Q000503:physiopathology; D015154:Esophageal Motility Disorders / Q000150:complications* / Q000453:epidemiology / Q000503:physiopathology; D050782:Esophageal pH Monitoring; D004947:Esophagus / Q000503:physiopathology*; D005260:Female; D005764:Gastroesophageal Reflux / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D005769:Gastrointestinal Motility; D006356:Heartburn / Q000209:etiology / Q000503:physiopathology; D006801:Humans; D008297:Male; D008365:Manometry; D008875:Middle Aged; D009119:Muscle Contraction; D011312:Pressure; D015995:Prevalence; D012737:Sex Factors; D016683:Supine Position