title: Risk factors for relapse of antineutrophil cytoplasmic antibody-associated vasculitis.
abstract: OBJECTIVE
  To determine the association between characteristics at diagnosis and the time to first relapse in a large cohort of patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV).
  
  
  METHODS
  We studied long-term followup data from 4 clinical trials that included newly diagnosed patients with a broad spectrum of AAV severity and manifestations. Patient and disease characteristics at baseline were used in competing risk regression models with relapse as the event of interest and death as the competing event.
  
  
  RESULTS
  We assessed 535 patients with 1,804 patient-years at risk of relapse. At diagnosis, the median age was 60.7 years (interquartile range [IQR] 48.8-69.1 years), 284 patients (53%) had granulomatosis with polyangiitis (Wegener's), and the median creatinine level was 203 μmoles/liter (IQR 97-498). A total of 201 patients (38%) experienced a relapse and 133 patients (25%) died, 96 of whom had not had prior relapse. Anti-proteinase 3 antibodies (subhazard ratio [sHR] 1.62 [95% confidence interval 1.39-1.89]) and cardiovascular involvement (sHR 1.59 [95% confidence interval 1.07-2.37]) were independently associated with a higher risk of relapse. Compared with patients with a creatinine level ≤100 μmoles/liter, patients with higher creatinine levels had a lower risk of relapse (sHR 0.81 [95% confidence interval 0.77-0.85] for a creatinine level of 101-200 μmoles/liter; sHR 0.39 [95% confidence interval 0.22-0.69] for a creatinine level >200 μmoles/liter).
  
  
  CONCLUSIONS
  Relapse of disease is common for patients with AAV. A creatinine level >200 μmoles/liter at the time of diagnosis is strongly associated with a reduced risk of relapse and may help guide monitoring and treatment of patients with AAV.
authors.affiliation: Division of Nephrology, St. Joseph's Hospital, Hamilton, Ontario, Canada. lastwalsh1975@gmail.com
authors.forename: Michael
authors.initials: M
authors.lastname: Walsh
authors.forename: Oliver
authors.initials: O
authors.lastname: Flossmann
authors.forename: Annelies
authors.initials: A
authors.lastname: Berden
authors.forename: Kerstin
authors.initials: K
authors.lastname: Westman
authors.forename: Peter
authors.initials: P
authors.lastname: Höglund
authors.forename: Coen
authors.initials: C
authors.lastname: Stegeman
authors.forename: David
authors.initials: D
authors.lastname: Jayne
mesh_terms: D000328:Adult; D000368:Aged; D056648:Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000276:immunology*; D002986:Clinical Trials as Topic; D003404:Creatinine / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012307:Risk Factors
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D003404:Creatinine