title: Outcomes from studies of antineutrophil cytoplasm antibody associated vasculitis: a systematic review by the European League Against Rheumatism systemic vasculitis task force.
abstract: OBJECTIVE
  We undertook a systematic literature review as a background to the European League Against Rheumatism (EULAR) recommendations for conducting clinical trials in anti-neutrophil cytoplasm antibody associated vasculitis (AAV), and to assess the quality of evidence for outcome measures in AAV.
  
  
  METHODS
  Using a systematic Medline search, we categorised the identified studies according to diagnoses. Factors affecting remission, relapse, renal function and overall survival were identified.
  
  
  RESULTS
  A total of 44 papers were reviewed from 502 identified by our search criteria. There was considerable inconsistency in definitions of end points. Remission rates varied from 30% to 93% in Wegener granulomatosis (WG), 75% to 89% in microscopic polyangiitis (MPA) and 81% to 91% in Churg-Strauss syndrome (CSS). The 5-year survival for WG, MPA and CSS was 74-91%, 45-76% and 60-97%. Relapse (variably defined) was common in the first 2 years but the frequency varied: 18% to 60% in WG, 8% in MPA, and 35% in CSS. The rate of renal survival in WG varied from 23% at 15 months to 23% at 120 months.
  
  
  METHODS
  used to assess morbidity varied between studies. Ignoring the variations in definitions of the stage of disease, factors influencing remission, relapse, renal and overall survival included immunosuppressive therapy used, type of organ involvement, presence of ANCA, older age and male gender.
  
  
  CONCLUSIONS
  Factors influencing remission, relapse, renal and overall survival include the type of immunosuppressive therapy used, pattern of organ involvement, presence of ANCA, older age and male gender. Methodological variations between studies highlight the need for a consensus on terminology and definitions for future conduct of clinical studies in AAV.
authors.affiliation: Botnar Research Centre, University of Oxford, Windmill Road, Oxford OX3 7LD, UK.
authors.forename: C
authors.initials: C
authors.lastname: Mukhtyar
authors.forename: O
authors.initials: O
authors.lastname: Flossmann
authors.forename: B
authors.initials: B
authors.lastname: Hellmich
authors.forename: P
authors.initials: P
authors.lastname: Bacon
authors.forename: M
authors.initials: M
authors.lastname: Cid
authors.forename: J W
authors.initials: JW
authors.lastname: Cohen-Tervaert
authors.forename: W L
authors.initials: WL
authors.lastname: Gross
authors.forename: L
authors.initials: L
authors.lastname: Guillevin
authors.forename: D
authors.initials: D
authors.lastname: Jayne
authors.forename: A
authors.initials: A
authors.lastname: Mahr
authors.forename: P A
authors.initials: PA
authors.lastname: Merkel
authors.forename: H
authors.initials: H
authors.lastname: Raspe
authors.forename: D
authors.initials: D
authors.lastname: Scott
authors.forename: J
authors.initials: J
authors.lastname: Witter
authors.forename: H
authors.initials: H
authors.lastname: Yazici
authors.forename: R A
authors.initials: RA
authors.lastname: Luqmani
mesh_terms: D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood*; D015267:Churg-Strauss Syndrome / Q000188:drug therapy / Q000276:immunology; D003520:Cyclophosphamide / Q000627:therapeutic use; D019317:Evidence-Based Medicine; D005938:Glucocorticoids / Q000627:therapeutic use; D014890:Granulomatosis with Polyangiitis / Q000188:drug therapy; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D012008:Recurrence; D012074:Remission Induction; D012307:Risk Factors; D016019:Survival Analysis; D016896:Treatment Outcome; D014657:Vasculitis / Q000188:drug therapy* / Q000276:immunology
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D005938:Glucocorticoids; D007166:Immunosuppressive Agents; D003520:Cyclophosphamide