title: Predictors of relapse and treatment outcomes in biopsy-proven giant cell arteritis: a retrospective cohort study.
abstract: OBJECTIVE
  To evaluate characteristics of relapse, relapse rates, treatment and outcomes among patients with biopsy-proven GCA in a large, single-institution cohort.
  
  
  METHODS
  We conducted a retrospective review of all patients with biopsy-proven GCA from 1998 to 2013. Demographic, clinical, laboratory and treatment data at presentation and during follow-up were collected. Comparisons by relapse rate were performed using chi-square tests. Prednisone discontinuation by initial oral dose ≤40 and >40 mg/day was compared using Cox models.
  
  
  RESULTS
  The cohort included 286 patients [74% female, mean age at diagnosis 75.0 years (s.d. 7.6), median follow-up 5.1 years). During follow-up, 73 patients did not relapse, 80 patients had one relapse and 133 had two or more relapses. The first relapse occurred during the first year in 50% of patients, by 2 years in 68% and by 5 years in 79%. More patients with established hypertension (P = 0.007) and diabetes (P = 0.039) at GCA diagnosis were in the high relapse rate group ( ≥ 0.5 relapses/year) and more females were in the low or high relapse groups than in the no relapse group (P = 0.034). Patients receiving an initial oral prednisone dose >40 mg/day were able to reach a dose of <5 mg/day [hazard ratio (HR) 1.46 (95% CI 1.09, 1.96)] and discontinue prednisone [HR 1.56 (95% CI 1.09, 2.23)] sooner than patients receiving ≤40 mg/day without an increase in observed glucocorticoid-associated adverse events.
  
  
  CONCLUSIONS
  Females and patients with hypertension or diabetes at GCA diagnosis have more relapses during follow-up. Patients treated with an initial oral prednisone dose >40 mg/day achieved earlier prednisone discontinuation.
authors.affiliation: Department of Internal Medicine, Universidad del Desarrollo, Clinica Alemana de Santiago, Santiago, Chile.
authors.forename: Cristian
authors.initials: C
authors.lastname: Labarca
authors.affiliation: Division of Rheumatology, Department of Medicine.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Koster
authors.affiliation: Division of Rheumatology, Department of Medicine, Division of Biostatistics and.
authors.forename: Cynthia S
authors.initials: CS
authors.lastname: Crowson
authors.affiliation: Division of Rheumatology, Department of Medicine.
authors.forename: Ashima
authors.initials: A
authors.lastname: Makol
authors.affiliation: Division of Rheumatology, Department of Medicine.
authors.forename: Steven R
authors.initials: SR
authors.lastname: Ytterberg
authors.affiliation: Division of Rheumatology, Department of Medicine, Division of Epidemiology, Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA.
authors.forename: Eric L
authors.initials: EL
authors.lastname: Matteson
authors.affiliation: Division of Rheumatology, Department of Medicine, warrington.kenneth@mayo.edu.
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Warrington
mesh_terms: D000284:Administration, Oral; D000368:Aged; D001706:Biopsy / Q000379:methods*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005500:Follow-Up Studies; D013700:Giant Cell Arteritis / Q000188:drug therapy / Q000401:mortality / Q000473:pathology*; D005938:Glucocorticoids / Q000008:administration & dosage; D006801:Humans; D008297:Male; D008875:Middle Aged; D008910:Minnesota / Q000453:epidemiology; D011239:Prednisolone / Q000008:administration & dosage*; D012008:Recurrence; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D016896:Treatment Outcome
chemical_list: D005938:Glucocorticoids; D011239:Prednisolone
keywords: adverse events; cohort; diabetes; giant cell arteritis; glucocorticoids; hypertension; relapse; retrospective