The Incidence of Primary Systemic Vasculitis in Jerusalem: A 20-year Hospital-based Retrospective Study.

OBJECTIVE: The incidence of primary systemic vasculitides varies among different geographic regions and ethnic origins. The aim of this study was to examine the incidence rates of vasculitides in the Jerusalem Jewish population, and to examine possible trends in incidence rates over a 20-year period. METHODS: The clinical databases of inpatients at the 2 medical centers in Jerusalem were searched for patients with vasculitis diagnosed between 1990-2009. Individual records were then reviewed by one of the authors. The significance of trends in incidence rates throughout the study period was evaluated by Pearson correlation coefficient. RESULTS: The average annual incidence rate of polyarteritis nodosa was 3.6/million adults (95% CI 1.6-4.7). Incidence rates did not change significantly during this period (r = 0.39, p = 0.088). The incidence of granulomatosis with polyangiitis (GPA) was 4.1 (2.2-5.9) for the whole period, during which it increased significantly (r = 0.53, p < 0.05). The incidence of microscopic polyangiitis (MPA) was lower: 2.3 (1.2-3.5)/million. It also increased significantly (r = 0.55, p < 0.05). The incidence of eosinophilic granulomatosis with polyangiitis was 1.2 (0.4-1.9), which remained stable throughout the study period. The incidence of Takayasu arteritis was 2.1/million (95% CI 1.2-2.9), and it also remained stable. Giant cell arteritis (GCA) incidence was 8.1 (5.7-10.6)/100,000 population aged 50 years or older. In sharp contrast with other vasculitides, its incidence decreased significantly throughout the study period (r = -0.61, p < 0.01). CONCLUSION: The incidence rates of vasculitides in the Jewish population of Jerusalem are in the lower range of global incidence rates. While GPA and MPA incidence are increasing, GCA incidence is decreasing.