title: Maximum upper esophageal sphincter (UES) admittance: a non-specific marker of UES dysfunction.
abstract: BACKGROUND
  Assessment of upper esophageal sphincter (UES) motility is challenging, as functionally, UES relaxation and opening are distinct. We studied novel parameters, UES admittance (inverse of nadir impedance), and 0.2-s integrated relaxation pressure (IRP), in patients with cricopharyngeal bar (CPB) and motor neuron disease (MND), as predictors of UES dysfunction.
  
  
  METHODS
  Sixty-six healthy subjects (n = 50 controls 20-80 years; n = 16 elderly >80 years), 11 patients with CPB (51-83 years) and 16 with MND (58-91 years) were studied using pharyngeal high-resolution impedance manometry. Subjects received 5 × 5 mL liquid (L) and viscous (V) boluses. Admittance and IRP were compared by age and between groups. A p < 0.05 was considered significant.
  
  
  RESULTS
  In healthy subjects, admittance was reduced (L: p = 0.005 and V: p = 0.04) and the IRP higher with liquids (p = 0.02) in older age. Admittance was reduced in MND compared to both healthy groups (Young: p < 0.0001 for both, Elderly L: p < 0.0001 and V: p = 0.009) and CPB with liquid (p = 0.001). Only liquid showed a higher IRP in MND patients compared to controls (p = 0.03), but was similar to healthy elderly and CPB patients. Only admittance differentiated younger controls from CPB (L: p = 0.0002 and V: p < 0.0001), with no differences in either parameter between CPB and elderly subjects.
  
  
  CONCLUSIONS
  The effects of aging and pathology were better discriminated by UES maximum admittance, demonstrating greater statistical confidence across bolus consistencies as compared to 0.2-s IRP. Maximum admittance may be a clinically useful determinate of UES dysfunction.
authors.affiliation: Gastroenterology & Hepatology, Southern Adelaide Local Health Network, Adelaide, SA, Australia.|School of Medicine, Flinders University of South Australia, Adelaide, SA, Australia.
authors.forename: C
authors.initials: C
authors.lastname: Cock
authors.affiliation: Gastroenterology & Hepatology, Southern Adelaide Local Health Network, Adelaide, SA, Australia.
authors.forename: L
authors.initials: L
authors.lastname: Besanko
authors.affiliation: Gastroenterology Unit, Women's and Children's Health Network, Adelaide, SA, Australia.
authors.forename: S
authors.initials: S
authors.lastname: Kritas
authors.affiliation: Gastroenterology & Hepatology, Southern Adelaide Local Health Network, Adelaide, SA, Australia.
authors.forename: C M
authors.initials: CM
authors.lastname: Burgstad
authors.affiliation: Gastroenterology & Hepatology, Southern Adelaide Local Health Network, Adelaide, SA, Australia.
authors.forename: A
authors.initials: A
authors.lastname: Thompson
authors.affiliation: Gastroenterology & Hepatology, Southern Adelaide Local Health Network, Adelaide, SA, Australia.
authors.forename: R
authors.initials: R
authors.lastname: Heddle
authors.affiliation: Gastroenterology & Hepatology, Southern Adelaide Local Health Network, Adelaide, SA, Australia.|School of Medicine, Flinders University of South Australia, Adelaide, SA, Australia.
authors.forename: R J L
authors.initials: RJ
authors.lastname: Fraser
authors.affiliation: School of Medicine, Flinders University of South Australia, Adelaide, SA, Australia.|Gastroenterology Unit, Women's and Children's Health Network, Adelaide, SA, Australia.|School of Paediatrics and Reproductive Health, University of Adelaide, Adelaide, SA, Australia.
authors.forename: T I
authors.initials: TI
authors.lastname: Omari
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D003679:Deglutition / Q000502:physiology*; D003680:Deglutition Disorders / Q000503:physiopathology*; D017097:Electric Impedance; D049631:Esophageal Sphincter, Upper / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry; D008875:Middle Aged; D055815:Young Adult
keywords: admittance; high-resolution impedance manometry; pressure flow analysis; upper esophageal sphincter