Incidence and survival rates in Wegener's granulomatosis, microscopic polyangiitis, Churg-Strauss syndrome and polyarteritis nodosa

Rheumatology (Oxford). 2009 Dec;48(12):1560-5. doi: 10.1093/rheumatology/kep304. Epub 2009 Oct 1.


Objective: To estimate the incidence of and survival rates for WG, microscopic polyangiitis (MPA), Churg-Strauss syndrome (CSS) and PAN within a defined population in southern Sweden.

Methods: Cases were retrieved using hospital records and a serology database. All new cases of WG, MPA, CSS and PAN between 1997 and 2006 were included, provided they met pre-defined criteria, and were followed until 30 June 2008. The study area comprised two health care districts with a total population of 641 000. The standardized mortality ratio (SMR) was estimated using Swedish population data as a reference.

Results: A total of 140 (WG, 63; MPA 65; CSS 6; and PAN 6) cases (52% women) with a median age of 67.6 (range 20-96) years fulfilled the inclusion criteria. The annual incidence per million of the population (95% CI) was estimated to be 9.8 (7.4-12.2) for WG, 10.1 (7.7-12.6) for MPA and 0.9 (0-1.7) for both CSS and PAN. The highest incidence was found in patients aged >or=75 years (79.1/million). The 1- and 5-year survival rates were 87.8 and 71.6% for all patients, but lower for MPA (80 and 55%) compared with WG (95 and 83%; P = 0.001), although the difference was not significant in the multivariate analysis. The SMR was 2.77 (95% CI 2.02, 3.71) for all patients.

Conclusions: The incidence of WG and MPA was equal in our district, but there was a difference in survival rates related to age and renal function. A progressive increase in age-specific incidence rates was observed.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Age Distribution
  • Aged
  • Aged, 80 and over
  • Churg-Strauss Syndrome / epidemiology
  • Epidemiologic Methods
  • Female
  • Granulomatosis with Polyangiitis / epidemiology
  • Humans
  • Male
  • Microscopic Polyangiitis / epidemiology
  • Middle Aged
  • Polyarteritis Nodosa / epidemiology
  • Seasons
  • Sex Distribution
  • Sweden / epidemiology
  • Systemic Vasculitis / epidemiology*
  • Young Adult