Hepatic steatosis index at diagnosis has the potential for forecasting end-stage kidney disease in patients with antineutrophil cytoplasmic antibody-associated vasculitis

OBJECTIVE: This study evaluated whether the hepatic steatosis index (HSI) at antineutrophil cytoplasmic antibody-associated vasculitis (AAV) diagnosis could forecast poor outcomes during the disease course in AAV patients. METHODS: This study included 260 AAV patients. The equation for HSI is as follows HSI=8×(alanine aminotransferase/aspartate aminotransferase)+body mass index+(2, diabetes mellitus)+(2, female). The cut-off of HSI was obtained using the receiver operating characteristic curve. RESULTS: The median age of the 260 patients was 59.5 years, and 65.0% were female. Among the continuous variables excluding the parameters composing the equation for HSI, HSI was significantly correlated with Birmingham vasculitis activity score, five-factor score, haemoglobin, blood urea nitrogen, serum creatinine, and total cholesterol. Among poor outcomes, the area under the curve of HSI for end-stage renal disease (ESRD) was significant, and the cut-off of HSI for ESRD was set at ≤30.82. AAV patients with HSI ≤30.82 exhibited a significantly higher risk of ESRD (relative risk 3.489) and a significantly lower cumulative ESRD-free survival rate than those with HSI >30.82. CONCLUSION: This study is the first to demonstrate that HSI at AAV diagnosis could forecast ESRD during the disease course in AAV patients.