Epidemiology of ANCA associated vasculitis
AbstractANCA associated vasculitis (AAV) comprises three syndromes with systemic vasculitis (Wegener’s granulomatosis (WG), Churg Strauss syndrome (CSS) and icroscopic polyangiitis (MPA)), which all involve small and medium sized vessels and are associated with antibodies against cytoplasmatic antibodies in neutrophils (ANCA). Polyarteritis nodosa (PAN) is included in this review as it also affects medium sized vessels, and has many clinical findings in common with the AAV.
Since the recognition of ANCA, increasing data have become available on the epidemiology of these vasculitidis. WG constitutes half of the AAV and its prevalence has increased from 30/million in the late 1980’s in the USA to 160/million in this century in northern Europe. The prevalence for the whole group of primary systemic vasculitides is now 300/million in Sweden. The annual incidence of WG increased from 6.0/million to 14/million during the 1990’s in Tromsø, but it is unknown if this is a true increase or the result of an increased awareness of the diagnosis. For the whole group of AAV, the annual incidence in most more recent studies is relatively constant over time and by geographical location, ranging from 13 to 21/million. Nonetheless there are interesting differences in the prevalence of specific vasculitis between different geographical areas, as well as for sub specificities of ANCA.
There seems to be a South-North gradient for WG and PR3-ANCA with high figures reported from northern Europe and southern New Zealand. In European studies WG is 90% PR3-ANCA positive. MPA which is predominantly MPO-ANCA associated are more frequent in the Mediterranean countries and also has an increasing gradient towards east-Asia, as almost all AAV in China and Japan are diagnosed as MPA, predominantly MPO-ANCA positive.
There are also some ethnic and gender differences. WG is most prevalent among Caucasians in the USA and in people with European ancestors in Paris and in New Zealand, less frequent in Africans and Asians. Several studies have shown that the highest incidence of WG is in males 60-70 years old. Females are younger at onset, and in children WG is most frequent in girls. With better treatment (cyclophosphamide and corticosteroids), the survival of AAV has increased considerably. However disease control is not optimal, as most of the vasculitis present a remitting-relapsing course and organ damage is considerable. Hence, we are still looking to improve treatment regimens
Copyright (c) 2015 Norsk epidemiologi
This work is licensed under a Creative Commons Attribution 4.0 International License.
Norsk Epidemiologi licenses all content of the journal under a Creative Commons Attribution (CC-BY) licence. This means, among other things, that anyone is free to copy and distribute the content, as long as they give proper credit to the author(s) and the journal. For further information, see Creative Commons website for human readable or lawyer readable versions.
Authors who publish with this journal agree to the following terms:
1. Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
2. Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
3. Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).