title: Functional impact of a spectrum of interstitial lung abnormalities in rheumatoid arthritis.
abstract: BACKGROUND
  Approximately 10% of patients with rheumatoid arthritis (RA) have interstitial lung disease (ILD), and one-third have subclinical ILD on chest CT scan. In this study, we aimed to further characterize functional decrements in a spectrum of RA-associated ILD.
  
  
  METHODS
  All subjects were enrolled in the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study (BRASS). The presence of interstitial lung abnormalities (ILAs) on clinically indicated chest CT scans was determined using a previously validated sequential reading method. Univariate and multivariate analyses were used to assess the association between degree of ILAs and physiologic, functional, and demographic variables of interest.
  
  
  RESULTS
  Of 1,145 BRASS subjects, 91 subjects (8%) were included in this study. Twelve had radiologically severe ILAs, 34 had ILAs, and 38 had no ILAs on CT scan. Subjects with radiologically severe ILAs were older (P = .0037), had increased respiratory symptoms (cough, P = .027; dyspnea, P = .010), and more severe RA disease (rheumatoid factor, P = .018; total swollen joints, P = .046) compared with subjects with no ILAs. Participants also had a trend toward having an increased smoking history (P = .16) and having lower FVC % predicted (77% vs 94%, P = .097) and diffusion capacity of carbon monoxide % predicted (52% vs 77%, P = .068). Similar but attenuated increases in respiratory symptoms, functional decrements, and RA disease severity were observed in subjects with ILAs compared with those with no ILAs.
  
  
  CONCLUSIONS
  We have shown that patients with RA have varying degrees of ILAs that are associated with a spectrum of functional and physiologic decrements. Our findings suggest that improved risk stratification and detection of ILAs will provide a therapeutic window that could improve RA-ILD outcomes.
authors.affiliation: Pulmonary and Critical Care Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Tracy J
authors.initials: TJ
authors.lastname: Doyle
authors.affiliation: Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA.
authors.forename: Paul F
authors.initials: PF
authors.lastname: Dellaripa
authors.affiliation: Division of Rheumatology, Rhode Island Hospital, Providence RI.
authors.forename: Kerri
authors.initials: K
authors.lastname: Batra
authors.affiliation: Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA.
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Frits
authors.affiliation: Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA.
authors.forename: Christine K
authors.initials: CK
authors.lastname: Iannaccone
authors.affiliation: Center for Pulmonary Functional Imaging, Brigham and Women's Hospital, Boston, MA; Department of Radiology, Brigham and Women's Hospital, Boston, MA.
authors.forename: Hiroto
authors.initials: H
authors.lastname: Hatabu
authors.affiliation: Center for Pulmonary Functional Imaging, Brigham and Women's Hospital, Boston, MA; Department of Radiology, Brigham and Women's Hospital, Boston, MA.
authors.forename: Mizuki
authors.initials: M
authors.lastname: Nishino
authors.affiliation: Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA.
authors.forename: Michael E
authors.initials: ME
authors.lastname: Weinblatt
authors.affiliation: Division of Rheumatology, University of Miami Miller School of Medicine, Miami FL.
authors.forename: Dana P
authors.initials: DP
authors.lastname: Ascherman
authors.affiliation: Pulmonary and Critical Care Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: George R
authors.initials: GR
authors.lastname: Washko
authors.affiliation: Pulmonary and Critical Care Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA; Channing Laboratory, Brigham and Women's Hospital, Boston, MA.
authors.forename: Gary M
authors.initials: GM
authors.lastname: Hunninghake
authors.affiliation: Pulmonary and Critical Care Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Augustine M K
authors.initials: AMK
authors.lastname: Choi
authors.affiliation: Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA.
authors.forename: Nancy A
authors.initials: NA
authors.lastname: Shadick
authors.affiliation: Pulmonary and Critical Care Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA; Lovelace Respiratory Research Institute, Albuquerque, NM. Electronic address: irosas@rics.bwh.harvard.edu.
authors.forename: Ivan O
authors.initials: IO
authors.lastname: Rosas
mesh_terms: D000368:Aged; D001172:Arthritis, Rheumatoid / Q000150:complications*; D005260:Female; D005500:Follow-Up Studies; D005541:Forced Expiratory Volume / Q000502:physiology*; D006801:Humans; D008168:Lung; D017563:Lung Diseases, Interstitial / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D012129:Respiratory Function Tests; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed / Q000379:methods