Risk factors for relapse of antineutrophil cytoplasmic antibody-associated vasculitis

Objective To determine the association between characteristics at diagnosis and the time to first relapse in a large cohort of patients with antineutrophil cytoplasmic antibodyassociated 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 mu moles/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 200 mu moles/liter).Conclusion. Relapse of disease is common for patients with AAV. A creatinine level >200 mu moles/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.