title: Discriminating dominant computed tomography phenotypes in smokers without or with mild COPD.
abstract: BACKGROUND
  Finding phenotypes within COPD patients may prove imperative for optimizing treatment and prognosis. We hypothesized that it would be possible to discriminate emphysematous, large airway wall thickening and small airways disease dominant phenotypes.
  
  
  METHODS
  Inspiratory and expiratory CTs were performed in 1140 male smokers without or with mild COPD to quantify emphysema, airway wall thickness and air trapping. Spirometry, residual volume to total lung capacity (RV/TLC) and diffusion capacity (Kco) were measured. Dominant phenotype (emphysema, airway wall thickening or air trapping dominant) was defined as one of the respective CT measure in the upper quartile, with the other measures not in the upper quartile.
  
  
  RESULTS
  573 subjects had any of the three CT measures in the upper quartile. Of these, 367 (64%) were in a single dominant group and 206 (36%) were in a mixed group. Airway wall thickening dominance was associated with younger age (p < 0.001), higher body mass index (p < 0.001), more wheezing (p < 0.05) and lower FEV1 %predicted (p < 0.001). Emphysema dominant subjects had lower FEV1/FVC (p < 0.05) and Kco %predicted (p < 0.05). There was no significant difference in respiratory related hospitalizations (p = 0.09).
  
  
  CONCLUSIONS
  CT measures can discriminate three different CT dominant groups of disease in male smokers without or with mild COPD.
  
  
  BACKGROUND
  ISRCTN63545820, registered at www.trialregister.nl.
authors.affiliation: Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands. Electronic address: fmohamedhoesein@gmail.com.
authors.forename: Firdaus A A
authors.initials: FA
authors.lastname: Mohamed Hoesein
authors.affiliation: Fraunhofer MEVIS, Institute for Medical Image Computing, Bremen, Germany. Electronic address: Michael.Schmidt@mevis.fraunhofer.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Schmidt
authors.affiliation: Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands. Electronic address: metsonno@gmail.com.
authors.forename: Onno M
authors.initials: OM
authors.lastname: Mets
authors.affiliation: Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands. Electronic address: h.gietema@umcutrecht.nl.
authors.forename: Hester A
authors.initials: HA
authors.lastname: Gietema
authors.affiliation: Department of Respiratory Medicine, Division of Heart & Lungs, University Medical Center Utrecht, Utrecht, The Netherlands. Electronic address: j.w.j.lammers@umcutrecht.nl.
authors.forename: Jan-Willem J
authors.initials: JW
authors.lastname: Lammers
authors.affiliation: Department of Respiratory Medicine, Division of Heart & Lungs, University Medical Center Utrecht, Utrecht, The Netherlands. Electronic address: p.zanen@umcutrecht.nl.
authors.forename: Pieter
authors.initials: P
authors.lastname: Zanen
authors.affiliation: Department of Public Health, Erasmus MC, Rotterdam, The Netherlands. Electronic address: h.dekoning@erasmusmc.nl.
authors.forename: Harry J
authors.initials: HJ
authors.lastname: de Koning
authors.affiliation: Department of Public Health, Erasmus MC, Rotterdam, The Netherlands. Electronic address: c.vanderaalst@erasmusmc.nl.
authors.forename: Carlijn
authors.initials: C
authors.lastname: van der Aalst
authors.affiliation: Department of Radiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands. Electronic address: m.oudkerk@umcg.nl.
authors.forename: Matthijs
authors.initials: M
authors.lastname: Oudkerk
authors.affiliation: Department of Radiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands. Electronic address: r.vliegenthart@rad.umcg.nl.
authors.forename: Rozemarijn
authors.initials: R
authors.lastname: Vliegenthart
authors.affiliation: Image Sciences Institute, University Medical Center Utrecht, The Netherlands. Electronic address: ivana.isgum@gmail.com.
authors.forename: Ivana
authors.initials: I
authors.lastname: Isgum
authors.affiliation: Department of Radiology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands. Electronic address: M.Prokop@rad.umcn.nl.
authors.forename: Mathias
authors.initials: M
authors.lastname: Prokop
authors.affiliation: Department of Radiology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands. Electronic address: b.vanginneken@rad.umcn.nl.
authors.forename: Bram
authors.initials: B
authors.lastname: van Ginneken
authors.affiliation: Department of Radiology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands. Electronic address: E.vanRikxoort@rad.umcn.nl.
authors.forename: Eva M
authors.initials: EM
authors.lastname: van Rikxoort
authors.affiliation: Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands. Electronic address: pimdejong@gmail.com.
authors.forename: Pim A
authors.initials: PA
authors.lastname: de Jong
mesh_terms: D000368:Aged; D056151:Airway Remodeling; D015992:Body Mass Index; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011237:Predictive Value of Tests; D011379:Prognosis; D029424:Pulmonary Disease, Chronic Obstructive / Q000000981:diagnostic imaging* / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology; D011656:Pulmonary Emphysema / Q000000981:diagnostic imaging / Q000473:pathology; D012115:Residual Volume; D012307:Risk Factors; D012680:Sensitivity and Specificity; D012907:Smoking / Q000009:adverse effects*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014109:Total Lung Capacity
keywords: Air trapping; Airway wall thickness; Chronic obstructive pulmonary disease; Computed tomography; Emphysema