title: Clinical characteristics associated with occurrence and poor prognosis of interstitial lung disease in rheumatoid arthritis.
abstract: OBJECTIVE
  To analyze clinical characteristics of interstitial lung disease (ILD) associated with rheumatoid arthritis (RA), especially in patients with poor prognosis.
  
  
  METHODS
  Seventy-seven RA patients with ILD and 231 age, sex, and disease duration-matched RA patients without ILD were enrolled in this retrospective study. Epidemiologic, clinical, and laboratory information were obtained through a medical chart review. Logistic regression analysis was used to estimate the risk of mortality in RA patients with ILD.
  
  
  RESULTS
  Compared to the RA without ILD group, the RA with ILD group had significantly higher titers of rheumatoid factor and the anti-cyclic citrullinated peptide (p = 0.001 for both), higher levels of C-reactive protein (CRP) at the time of RA diagnosis (p = 0.014), and a higher erythrocyte sedimentation rate (p = 0.022) and CRP levels (p < 0.001) throughout the 10-year follow-up period. These patients also received a higher mean daily dose of corticosteroids (p < 0.001). In the subgroup analysis of RA patients with ILD, 28 patients (36.4%) died during follow-up. Multivariate analysis revealed that older age at the time of ILD diagnosis was significantly associated with mortality. Usual interstitial pneumonia (UIP) subtype on high-resolution computed tomography (HRCT) was also suggested as a poor prognostic factor.
  
  
  CONCLUSIONS
  The survival of RA patients with ILD is adversely affected by age at the time of ILD diagnosis. RA-ILD patients diagnosed after age 65 or with a UIP subtype on HRCT may have a poor prognosis.
authors.forename: Ji Ae
authors.initials: JA
authors.lastname: Yang
authors.forename: Jeong Seok
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Jin Kyun
authors.initials: JK
authors.lastname: Park
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Eun Bong
authors.initials: EB
authors.lastname: Lee
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Yeong Wook
authors.initials: YW
authors.lastname: Song
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Eun Young
authors.initials: EY
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D000075422:Anti-Citrullinated Protein Antibodies / Q000097:blood; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000150:complications*; D001799:Blood Sedimentation; D002097:C-Reactive Protein / Q000378:metabolism; D005260:Female; D006801:Humans; D017563:Lung Diseases, Interstitial / Q000097:blood / Q000175:diagnosis / Q000209:etiology / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D012217:Rheumatoid Factor / Q000097:blood
chemical_list: D000075422:Anti-Citrullinated Protein Antibodies; D002097:C-Reactive Protein; D012217:Rheumatoid Factor
keywords: Arthritis, rheumatoid; Lung diseases, interstitial; Rheumatoid arthritis-associated interstitial lung disease