title: Nasal nitric oxide is dependent on sinus obstruction in allergic rhinitis.
abstract: OBJECTIVE
  The aim of this study was to evaluate the associations between nasal nitric oxide and nasal symptoms, sinus opacification, and markers of allergic inflammation in allergic and in nonallergic rhinitis while taking into account the effect of sinus obstruction.
  
  
  METHODS
  We studied 175 young adult subjects divided into three groups: 1) allergic rhinitis, 2) nonallergic rhinitis, and 3) controls.
  
  
  METHODS
  We measured nasal nitric oxide using the breath-holding method and exhaled nitric oxide and scored semiquantitatively nasal computed tomography scans for opacification and obstruction. We also assessed the visual analogue scores of nasal symptoms, eosinophil count, and interleukin-13 mRNA levels in nasal biopsies.
  
  
  RESULTS
  The level of nasal nitric oxide correlated with exhaled nitric oxide (r = 0.377, P < .001). In allergic rhinitis, nasal nitric oxide was elevated when compared to the controls, and an inverse correlation existed between the nasal nitric oxide level and sinus ostial obstruction (r = -0.272, P = .013). In nonallergic rhinitis, the level of nasal nitric oxide was similar to that of the controls. In allergic rhinitis, nasal nitric oxide correlated positively with the opacification score (r = 0.250, P = .033) and the nasal eosinophil count (r = 0.293, P = .030) of patients without a marked sinus ostial obstruction.
  
  
  CONCLUSIONS
  Sinus ostial obstruction lowers the level of nasal nitric oxide and reduces its value as an indicator of allergic mucosal inflammation. A high nasal nitric oxide level may be a useful marker of eosinophilic inflammation in the nasal cavity and indicate the absence of marked sinus ostial obstruction.
  
  
  METHODS
  3b.
authors.affiliation: Control of Hypersensitivity Diseases Team, Finnish Institute of Occupational Health, Helsinki, Finland.
authors.forename: Hille
authors.initials: H
authors.lastname: Suojalehto
authors.forename: Tapio
authors.initials: T
authors.lastname: Vehmas
authors.forename: Irmeli
authors.initials: I
authors.lastname: Lindström
authors.forename: David W
authors.initials: DW
authors.lastname: Kennedy
authors.forename: Maritta
authors.initials: M
authors.lastname: Kilpeläinen
authors.forename: Tuomas
authors.initials: T
authors.lastname: Plosila
authors.forename: Sauli
authors.initials: S
authors.lastname: Savukoski
authors.forename: Jukka
authors.initials: J
authors.lastname: Sipilä
authors.forename: Matti
authors.initials: M
authors.lastname: Varpula
authors.forename: Henrik
authors.initials: H
authors.lastname: Wolff
authors.forename: Harri
authors.initials: H
authors.lastname: Alenius
authors.forename: Elina
authors.initials: E
authors.lastname: Toskala
mesh_terms: D000328:Adult; D000367:Age Factors; D015415:Biomarkers / Q000378:metabolism; D001944:Breath Tests; D016022:Case-Control Studies; D045853:Exhalation / Q000502:physiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D015999:Multivariate Analysis; D015508:Nasal Obstruction / Q000453:epidemiology / Q000378:metabolism / Q000503:physiopathology*; D009569:Nitric Oxide / Q000493:pharmacokinetics*; D012016:Reference Values; D065631:Rhinitis, Allergic; D012221:Rhinitis, Allergic, Perennial / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D012737:Sex Factors; D055815:Young Adult
chemical_list: D015415:Biomarkers; D009569:Nitric Oxide
keywords: Nasal nitric oxide; computed tomography; eosinophils; exhaled nitric oxide; interleukin-13; rhinitis