2512: Contribution of the CALLY index at diagnosis to early prediction of all-cause mortality in patients with ANCA-associated vasculitis

Background/Purpose: This study retrospectively investigated whether the initial C-reactive protein (CRP)-albumin-lymphocyte (CALLY) index at diagnosis can contribute to early prediction of all-cause mortality during follow-up in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).

Methods: This study included 323 patients with AAV. Clinical data at AAV diagnosis and those during follow-up were collected. The CALLY index was calculated using the following equation: serum albumin (g/L) × lymphocyte count (/mm3) / CRP (mg/L) /10,000. The parameter of serum albumin (g/L) of an equation of the CALLY index was corrected by multiplying the measured serum albumin (g/dL) by 10.

Results: The median age was 61.0 years (36.2% male and 63.8% female). The median CALLY index was calculated as 0.48. Of the 323 patients, 45 (13.9%) died during the follow-up period of 53.7 months. In ROC curve analysis, the optimal cut-off of the CALLY index for all-cause mortality was determined as 0.55 (area 0.715). Patients with the CALLY index ≤0.55 at AAV diagnosis had a significantly higher risk for death (relative risk 7.294), and exhibited a significantly lower cumulative patients’ survival rate than those with the CALLY index >0.55. In multivariable Cox proportional hazard analysis, the CALLY index ≤0.55 (hazard ratio [HR] 3.913), age (HR 1.037) and male sex (HR 2.326) were independently associated with all-cause mortality during follow-up in patients with AAV.

Conclusion: This is the first study to demonstrate that the initial CALLY index at diagnosis could be useful in predicting all-cause mortality during follow-up in patients with AAV.