Epidemiological study of primary systemic vasculitides among adults in southern Spain and review of the main epidemiological studies.

Objectives: To study the incidence and prevalence of primary systemic vasculitides (PSV) in the Costa del Sol region (southern Spain) and to compare the major epidemiological studies in PSV with the results obtained in our area.
Methods: Retrospective study including permanent residents ≥14 years (or older) diagnosed with PSV at the Hospital Costa del Sol (Marbella, Spain) between 1994 and 2010. Epidemiological data were collected and the annual incidence rate during the study period and the prevalence in 2010 were calculated per million population, except for GCA, which was estimated per 100,000 population >50 years.
Results: Seventy-four adult patients were diagnosed with PSV, representing an annual incidence of 15.8 (95%CI 12.2-19.4) patients/million population. These diagnoses included 29 (39.1%) giant cell arteritis (GCA), 5 (6.7%) Takayasu's arteritis (TKA), 3 (4%) poly-arteritis nodosa (PAN), 29 (39.1%) antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) [10 (13.5%) granulomatosis with polyangiitis (GPA) (Wegener), 16 (21.6%) microscopic polyangiitis (MPA) and 3 (4%) eosinophilic granulomatosis with polyangiitis (EGPA) (Churg-Strauss)], 7 (9.4%) IgA vasculitis (Henoch-Schönlein) (IgAV) and one (1.3%) cryobulinaemic vasculitis (CV). The annual incidence and 2010 prevalence for each of the PSV, respectively, were: GCA: 2.2/12.2; TKA: 1.1/10.5; PAN: 0.6/2.6; AAV: 6.2/44.8 (GPA: 2.1/15.8; MPA: 3.4/23.8; EGPA: 0.6/5.3); IgAV: 1.5/7.9; and CV: 0.2/0.
Conclusions: The first epidemiological study of PSV in southern Spain corroborates their infrequency, with GCA and AAV as the PSV most often diagnosed. In southern Spain, the incidence and prevalence of PSV are lower than in northern Spain and in countries in the Northern Hemisphere.