title: Paraseptal emphysema: Prevalence and distribution on CT and association with interstitial lung abnormalities.
abstract: OBJECTIVE
  To investigate the prevalence and distribution of paraseptal emphysema on chest CT images in the Framingham Heart Study (FHS) population, and assess its impact on pulmonary function. Also pursued was the association with interstitial lung abnormalities.
  
  
  METHODS
  We assessed 2633 participants in the FHS for paraseptal emphysema on chest CT. Characteristics of the participants, including age, sex, smoking status, clinical symptoms, and results of pulmonary function tests, were compared between those with and without paraseptal emphysema. The association between paraseptal emphysema and interstitial lung abnormalities was investigated.
  
  
  RESULTS
  Of the 2633 participants, 86 (3%) had pure paraseptal emphysema (defined as paraseptal emphysema with no other subtypes of emphysema other than paraseptal emphysema or a very few centrilobular emphysema involved) in at least one lung zone. The upper zone of the lungs was almost always involved. Compared to the participants without paraseptal emphysema, those with pure paraseptal emphysema were significantly older, and were more frequently male and smokers (mean 64 years, 71% male, mean 36 pack-years, P<0.001) and had significantly decreased FEV1/FVC% (P=0.002), and diffusion capacity of carbon monoxide (DLCO) (P=0.002). There was a significant association between pure paraseptal emphysema and interstitial lung abnormalities (P<0.001).
  
  
  CONCLUSIONS
  The prevalence of pure paraseptal emphysema was 3% in the FHS population, predominantly affects the upper lung zone, and contributes to decreased pulmonary function. Cigarette smoking, aging, and male gender were the factors associated with the presence of paraseptal emphysema. Significant association between paraseptal emphysema and interstitial lung abnormalities was observed.
authors: Department of Radiology, Center for Pulmonary Functional Imaging, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02215, USA; Department of Radiology, Kinki University Faculty of Medicine, Osaka-Sayama, Japan. Electronic address: taraki@partners.org.
authors: Tetsuro
authors: T
authors: Araki
authors: Department of Radiology, Center for Pulmonary Functional Imaging, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02215, USA.
authors: Mizuki
authors: M
authors: Nishino
authors: The Pulmonary and Critical Care Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors: Oscar E
authors: OE
authors: Zazueta
authors: Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA.
authors: Wei
authors: W
authors: Gao
authors: Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA; The National Heart Lung and Blood Institute's Framingham Heart Study, Framingham, MA, USA.
authors: Josée
authors: J
authors: Dupuis
authors: Department of Radiology, Center for Pulmonary Functional Imaging, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02215, USA.
authors: Yuka
authors: Y
authors: Okajima
authors: Department of Medicine and Neurology, Boston University School of Medicine, Boston, MA, USA.
authors: Jeanne C
authors: JC
authors: Latourelle
authors: The Pulmonary and Critical Care Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors: Ivan O
authors: IO
authors: Rosas
authors: Department of Radiology, Kinki University Faculty of Medicine, Osaka-Sayama, Japan.
authors: Takamichi
authors: T
authors: Murakami
authors: The National Heart Lung and Blood Institute's Framingham Heart Study, Framingham, MA, USA; Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA, USA.
authors: George T
authors: GT
authors: O'Connor
authors: The Pulmonary and Critical Care Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors: George R
authors: GR
authors: Washko
authors: The Pulmonary and Critical Care Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors: Gary M
authors: GM
authors: Hunninghake
authors: Department of Radiology, Center for Pulmonary Functional Imaging, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02215, USA.
authors: Hiroto
authors: H
authors: Hatabu
mesh_terms: D000367:Age Factors; D000368:Aged; D002248:Carbon Monoxide; D005260:Female; D006801:Humans; D008168:Lung / Q000002:abnormalities* / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011656:Pulmonary Emphysema / Q000000981:diagnostic imaging*; D012129:Respiratory Function Tests; D012737:Sex Factors; D012907:Smoking; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D002248:Carbon Monoxide
keywords: CT; Interstitial lung abnormalities; Paraseptal emphysema