Epidemiology of vasculitides: differences between Japan, Europe and North America.

The epidemiology of systemic vasculitides differs between Japan, Europe and North America. Takayasu's arteritis occurs frequently in Japan, unlike giant cell arteritis. A collaborative international study comparing the epidemiology of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis between Japan and the United Kingdom (UK) demonstrated that microscopic polyangiitis and myeloperoxidase-ANCA were more common in Japan, whereas granulomatosis with polyangiitis and pronase 3-ANCA were more common in the UK. These differences may be attributed to differences in latitude and genetic backgrounds. These findings provide useful information on the aetiology and pathogenesis of primary systemic vasculitides in various geographical regions.