The proportion of patients who were smokers, had diabetes, and hypertension, and were dialysis-dependent was 38.1%, 28.9%, 82.1%, and 40.2% in the MPO-AAV group, and 54.0%, 36.5%, 78.7%, and 47.0% in the control group, respectively. Here, MPO is linked to anti-neutrophil cytoplasmic antibody-associated vasculitis.