title: Predictive factors for long-term outcome in polymyositis/dermatomyositis-associated interstitial lung diseases.
abstract: BACKGROUND
  Interstitial lung disease (ILD) is strongly associated with polymyositis (PM), dermatomyositis (DM), and clinically amyopathic dermatomyositis (CADM). It is also related to mortality. Previous studies have highlighted that the acute form of PM/DM/CADM-associated ILD (PM/DM/CADM-ILD) has a poor short-term prognosis. However, little is known about the long-term clinical features of patients with PM/DM/CADM-ILD. The aim of the present study is to clarify the clinical characteristics and the predictive factors for long-term outcomes in patients with PM/DM/CADM-ILD.
  
  
  METHODS
  Thirty-four patients with PM/DM/CADM-ILD who were followed up for more than 12 months were analyzed retrospectively. The patients were classified as "stable" or "deterioration" according to respiratory symptoms, serial changes in forced vital capacity (FVC) or arterial oxygen pressure, and radiologic findings during the follow-up period.
  
  
  RESULTS
  Twenty-six patients (76%) were in the stable group and eight patients (24%) were in the deterioration group. Home oxygen therapy was performed in six cases in the deterioration group because of chronic respiratory failure due to progression of ILD. The deterioration group, in comparison to the stable group, had a significantly lower %FVC and a higher positive rate for the anti-PL-7 antibody. Multivariate logistic regression analysis revealed that a positive anti-PL-7 antibody test and a lower %FVC were independently associated with deterioration during long-term follow-up.
  
  
  CONCLUSIONS
  Patients with PM/DM/CADM-ILD are at risk for chronic respiratory failure due to the deterioration of ILD during long-term follow-up. The presence of anti-PL-7 antibody and a lower %FVC at initial diagnosis may predict long-term deterioration in patients with PM/DM/CADM-ILD.
authors.affiliation: Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama Higashi-ku, Hamamatsu 431-3192, Japan. Electronic address: fujisawa@hama-med.ac.jp.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Fujisawa
authors.affiliation: Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama Higashi-ku, Hamamatsu 431-3192, Japan. Electronic address: hozumi@hama-med.ac.jp.
authors.forename: Hironao
authors.initials: H
authors.lastname: Hozumi
authors.affiliation: Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama Higashi-ku, Hamamatsu 431-3192, Japan. Electronic address: masato.k@hama-med.ac.jp.
authors.forename: Masato
authors.initials: M
authors.lastname: Kono
authors.affiliation: Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama Higashi-ku, Hamamatsu 431-3192, Japan. Electronic address: norieno@hama-med.ac.jp.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Enomoto
authors.affiliation: Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama Higashi-ku, Hamamatsu 431-3192, Japan. Electronic address: nakayuta@hama-med.ac.jp.
authors.forename: Yutaro
authors.initials: Y
authors.lastname: Nakamura
authors.affiliation: Department of Clinical Pharmacology and Therapeutics, Hamamatsu University School of Medicine, 1-20-1 Handayama Higashi-ku, Hamamatsu 431-3192, Japan. Electronic address: inui@hama-med.ac.jp.
authors.forename: Naoki
authors.initials: N
authors.lastname: Inui
authors.affiliation: Department of Rheumatology and Clinical Immunology, Kyoto University Hospital, 54 Shogoin-kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: ranran@kuhp.kyoto-u.ac.jp.
authors.forename: Ran
authors.initials: R
authors.lastname: Nakashima
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, 54 Shogoin-kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: imuray@kuhp.kyoto-u.ac.jp.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Imura
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, 54 Shogoin-kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: mimorit@kuhp.kyoto-u.ac.jp.
authors.forename: Tsuneyo
authors.initials: T
authors.lastname: Mimori
authors.affiliation: Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama Higashi-ku, Hamamatsu 431-3192, Japan. Electronic address: suda@hama-med.ac.jp.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Suda
mesh_terms: D000328:Adult; D000368:Aged; D002908:Chronic Disease; D003882:Dermatomyositis / Q000150:complications* / Q000503:physiopathology; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006931:Hyperbaric Oxygenation; D016015:Logistic Models; D017563:Lung Diseases, Interstitial / Q000150:complications* / Q000503:physiopathology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012131:Respiratory Insufficiency / Q000209:etiology*; D012189:Retrospective Studies; D013997:Time Factors; D014797:Vital Capacity
keywords: Anti-PL-7 antibody; Dermatomyositis; Interstitial lung disease; Outcome; Polymyositis