Clinical features of Korean elderly patients with antineutrophil cytoplasmic antibody-associated vasculitis

Background/Aims: We compared the clinical and laboratory data between elderly and non-elderly patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) at diagnosis; further, we investigated the predictors at diagnosis for all-cause mortality and end-stage renal disease (ESRD) occurrence during follow-up in Korean elderly patients with AAV. Methods: We reviewed the medical records of 191 AAV patients regarding clinical manifestations and laboratory results at diagnosis and during follow-up. The follow-up duration was defined as the period from diagnosis to death for deceased patients or to the time of dialysis for ESRD patients, or to the last visit. Elderly (n = 67) and non-elderly (n = 124) patients were grouped based on an age threshold of 65 years. Results: At diagnosis, elderly patients exhibited higher median Birmingham Vasculitis Activity Score (BVAS) and higher frequencies of ANCA positivity and pulmonary manifestations than non-elderly patients. Furthermore, elderly patients exhibited increased median white blood cell count, blood urea nitrogen (BUN), alkaline phosphatase, erythrocyte sedimentation rate, and C-reactive protein and decreased median hemoglobin. However, there were no significant differences in all-cause mortality and ESRD occurrence between elderly and non-elderly patients. Meanwhile, elderly patients exhibited lower cumulative patients' and ESRD-free survival rates than non-elderly patients. In the multivariable Cox hazards model, BUN, creatinine and serum albumin at diagnosis were independent predictors for ESRD occurrence, whereas there were no independent predictors at diagnosis for all-cause mortality. Conclusions: Elderly AAV patients exhibited substantially higher rates of all-cause mortality and ESRD occurrence during follow-up compared than non-elderly AAV patients.