Pan-immune-inflammation value at diagnosis independently predicts all-cause mortality in patients with antineutrophil cytoplasmic antibody-associated vasculitis

Objective. The pan-immune-inflammation value (PIIV), a novel, validated predictor of the prognosis of several diseases, has been recently introduced. We investigated whether PIIV at diagnosis could predict all-cause mortality during follow-up in patients with antineutrophil cytoplasmic antibody (ANCA)associated vasculitis (AAV). Methods. Medical records of 219 immunosuppressive drug-naïve patients with AAV were reviewed. PIIV was calculated as follows: neutrophil count (x 1000/m³) x monocyte count (x 1000/m³) x platelet count (x 1000/mm³) / lymphocyte count (x 1000/m³). Additionally, conventional risk factors of mortality, AAV-specific indices, and acute-phase reactants at diagnosis were evaluated. Results. The median age at diagnosis was 59.0 years and 32.9% of the patients were male. During follow-up, 24 patients (11.0%) died due to all causes. When the cut-off of PIIV at diagnosis for all-cause mortality was set at 1011.3, sensitivity and specificity of 52.0% and 71.2%, were attained (p=0.041). When AAV patients were divided into two groups according to the calculated cut-off, those with PIIV ≥1011.3 at diagnosis had a significantly lower cumulative survival rate than those without (p=0.009). In the multivariable Cox hazards model analysis, male gender (HR 2.307), FFS (HR 1.728) and PIIV ≥1011.3 (HR 2.689) were identified as significant and independent risk factors of all-cause mortality. Conclusion. PIIV at diagnosis exceeding the optimal cut-off for death could predict all-cause mortality during follow-up in AAV patients comparable to male gender and FFS at diagnosis.