Clinical perspective on serum periostin in antineutrophil-cytoplasmic antibody-associated vasculitis.

BACKGROUND/AIMS: This study evaluated the clinical utility of serum periostin measured at diagnosis in reflecting activity at diagnosis and predicting all-cause mortality during follow-up in patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV). METHODS: This study included 76 patients with AAV whose serum periostin was measured from sera collected and stored at diagnosis. The correlation of either serum periostin or the Birmingham Vasculitis Activity Score (BVAS) with other variables was evaluated. Cumulative survival rates were compared using Kaplan-Meier survival analysis. The variables at diagnosis were compared between deceased and surviving patients. Hazard ratios were obtained by Cox proportional hazard analysis. RESULTS: The median age of the 76 patients was 64.0 years and 60.5% were female. The median BVAS and serum periostin were 5.0 and 10.9 ng/mL, respectively. Five of the 76 patients (6.6%) died. Serum periostin was independently correlated with cross-sectional BVAS, the Vasculitis Damage Index (VDI), white blood cell count, and serum albumin. Patients with serum periostin ≥ 15.9 ng/mL at diagnosis had a significantly lower cumulative survival rate than those without. In addition to high VDI, dyslipidaemia frequency, and C-reactive protein, deceased patients showed higher serum periostin than surviving patients. In multivariable Cox analysis, however, only dyslipidaemia rather than serum periostin was identified as an independent predictor of all-cause mortality. CONCLUSION: This study is the first to demonstrate that serum periostin at diagnosis could independently reflect cross-sectional BVAS and further partially contribute to all-cause mortality prediction in patients with AAV.