Predictors of treatment resistance and relapse in antineutrophil cytoplasmic antibody-associated vasculitis: a study of 439 cases in a single Chinese center.

Treatment resistance and relapse in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) are major challenges for physicians. The aim of this study was to assess the risk factors for treatment resistance and relapse in a single-center cohort of Chinese patients with AAV. Four hundred thirty-nine consecutive patients with AAV were recruited for inclusion in this study. The value of various clinical and pathologic parameters for the prediction of treatment resistance and relapse was analyzed. Treatment resistance occurred in 47 (10.7%) of 439 patients and was independently associated with a higher serum creatinine level (odds ratio [OR] 1.087, 95% confidence interval [95% CI] 1.001-1.180, P = 0.047), a higher erythrocyte sedimentation rate (OR 1.009, 95% CI 1.001-1.018, P = 0.025), therapy with corticosteroids plus cyclophosphamide (OR 0.115, 95% CI 0.051-0.256, P = 0.000), and the presence of muscle pain (OR 0.249, 95% CI 0.083-0.747, P = 0.013). Relapse occurred in 128 (32.7%) of 392 patients in whom remission was achieved and was independently associated with lung involvement (hazard ratio [HR] 1.768, 95% CI 1.088-2.872, P = 0.021) and a lower serum creatinine level (HR 0.925, 95% CI 0.872-0.981, P = 0.009). In Chinese patients with AAV, lung involvement and lower serum creatinine levels were independently associated with an increased risk of relapse. Elevated serum creatinine levels were associated with treatment resistance.