title: Airway wall thickness on HRCT scans decreases with age and increases with smoking.
abstract: To investigate if age, gender and smoking are associated with airway wall thickness (AWT) measured by high resolution computed tomography (HRCT) and if higher AWT is associated with lower levels of pulmonary function in healthy current- and never-smokers with a wide age range.
  
  
  
  HRCT scans were performed in 99 subjects (48 never- and 51 current-smokers, median age 39 years [IQR 22 - 54], 57% males). The AWT at an internal perimeter of 10 mm (AWT Pi10) was calculated as an overall measurement of AWT, based on all measurements throughout the lungs. Extensive pulmonary function testing was performed in all subjects.
  
  
  
  Higher age was associated with a lower AWT Pi10 (b = -0.003, p < 0.001). Current-smokers had a higher AWT Pi10 than never-smokers (mean 0.49 mm versus 0.44 mm, p = 0.022). In multivariate analysis, age and current-smoking were independently associated with AWT Pi10 (age b = -0.002, p < 0.001, current-smoking b = 0.041, p = 0.021), whereas gender was not (b = 0.011, p = 0.552). Higher AWT Pi10 was associated with a lower FEV1, FEV1/FVC, FEF25-75and higher R5, R20 and X5.
  
  
  
  AWT decreases with higher age, possibly reflecting structural changes of the airways. Additionally, current-smokers have a higher AWT, possibly due to remodeling or inflammation. Finally, higher AWT is associated with a lower level of pulmonary function, even in this population of healthy subjects.
  
  
  
  This Study was registered at www.clinicaltrials.gov with number NCT00848406 on 19 February 2009.
authors.affiliation: Department of Pulmonary Diseases, University of Groningen, University Medical Center Groningen, PO Box 30.001, 9700 RB, Groningen, The Netherlands.|GRIAC Research Institute, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors.forename: Eef D
authors.initials: ED
authors.lastname: Telenga
authors.affiliation: Center for Medical Imaging North East Netherlands, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors.forename: Matthijs
authors.initials: M
authors.lastname: Oudkerk
authors.affiliation: Center for Medical Imaging North East Netherlands, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.|Department of Radiology, University of Groningen, University Medical Center Groningen, PO Box 30.001, 9700 RB, Groningen, The Netherlands.
authors.forename: Peter M A
authors.initials: PM
authors.lastname: van Ooijen
authors.affiliation: Center for Medical Imaging North East Netherlands, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.|Department of Radiology, University of Groningen, University Medical Center Groningen, PO Box 30.001, 9700 RB, Groningen, The Netherlands.
authors.forename: Rozemarijn
authors.initials: R
authors.lastname: Vliegenthart
authors.affiliation: Department of Pulmonary Diseases, University of Groningen, University Medical Center Groningen, PO Box 30.001, 9700 RB, Groningen, The Netherlands.|GRIAC Research Institute, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors.forename: Nick H T
authors.initials: NH
authors.lastname: Ten Hacken
authors.affiliation: Department of Pulmonary Diseases, University of Groningen, University Medical Center Groningen, PO Box 30.001, 9700 RB, Groningen, The Netherlands.|GRIAC Research Institute, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors.forename: Dirkje S
authors.initials: DS
authors.lastname: Postma
authors.affiliation: Department of Pulmonary Diseases, University of Groningen, University Medical Center Groningen, PO Box 30.001, 9700 RB, Groningen, The Netherlands. m.van.den.berge@umcg.nl.|GRIAC Research Institute, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands. m.van.den.berge@umcg.nl.
authors.forename: Maarten
authors.initials: M
authors.lastname: van den Berge
mesh_terms: D000328:Adult; D000375:Aging / Q000502:physiology*; D000403:Airway Resistance; D001980:Bronchi / Q000000981:diagnostic imaging* / Q000473:pathology*; D016022:Case-Control Studies; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009426:Netherlands; D011446:Prospective Studies; D012016:Reference Values; D012907:Smoking / Q000009:adverse effects / Q000503:physiopathology*; D013147:Spirometry; D014057:Tomography, X-Ray Computed; D014797:Vital Capacity; D055815:Young Adult
keywords: Age; Airway wall thickness; Computed tomography; Smoking