title: Epidemiology of granulomatosis with polyangiitis (Wegener's granulomatosis) in Northern Italy: a 15-year population-based study.
abstract: OBJECTIVE
  To investigate the epidemiology of granulomatosis with polyangiitis (GPA) over a 15-year period in a defined area of northern Italy.
  
  
  METHODS
  All patients with incident GPA diagnosed from January 1, 1995 to December 31, 2009 living in the Reggio Emilia area were identified by looking at computerized hospital discharge diagnoses, by contacting Reggio Emilia Hospital physicians and community-based specialists, and by checking the databases of the pathology and the laboratory departments and the Reggio Emilia district database for rare diseases. Patients were classified according to the European Medicines Agency (EMA) algorithm. Patients were followed up from the time of diagnosis until either their death or December 31, 2011. For each case, we identified 20 control subjects from the same geographic area matched for age and gender.
  
  
  RESULTS
  A total of 18 patients (7 men and 11 women) with GPA were identified. The overall age- and sex-adjusted incidence rate (IR) was 2.4 per million (95% CI: 1.2-3.5). The mean annual IR increased from 1.7/million/year during 1995-1999 to 3.4 during 2005-2009. The highest IR occurred in females aged 70-79 years (13.5 per million; 95% CI: 5.0-30.0) and in males aged ≥ 80 years (14.9 per million; 95% CI: 2.5-49.4). The prevalence of GPA on December 31, 2009 was 34.3 per million (95% CI: 20.3-54.2). The point prevalence per million increased from 17.8 (95% CI: 7.7-35.1) in 1999 to 34.3 (95% CI: 20.3-54.2) in 2009. Survival among individuals with GPA was significantly reduced compared to that observed in the matched control population (p < 0.001).
  
  
  CONCLUSIONS
  In the Italian population, GPA is very uncommon and GPA patients have reduced survival.
authors.affiliation: Rheumatology Unit, Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Arcispedale Santa Maria Nuova, Viale Risorgimento 80, 42123, Reggio Emilia, Italy.
authors.forename: Mariagrazia
authors.initials: M
authors.lastname: Catanoso
authors.affiliation: Rheumatology Unit, Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Arcispedale Santa Maria Nuova, Viale Risorgimento 80, 42123, Reggio Emilia, Italy.
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Macchioni
authors.affiliation: Rheumatology Unit, Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Arcispedale Santa Maria Nuova, Viale Risorgimento 80, 42123, Reggio Emilia, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Boiardi
authors.affiliation: Department of Nephrology, University Hospital of Parma, Parma, Italy.
authors.forename: Lucio
authors.initials: L
authors.lastname: Manenti
authors.affiliation: Internal Medicine Unit II, Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Arcispedale Santa Maria Nuova, Reggio Emilia, Italy.
authors.forename: Bruno
authors.initials: B
authors.lastname: Tumiati
authors.affiliation: Pathology Unit, Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Arcispedale Santa Maria Nuova, Reggio Emilia, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Cavazza
authors.affiliation: Epidemiology and Risk Communication Unit, Local Health Authority, Azienda USL di RE, Reggio Emilia, Italy.
authors.forename: Ferdinando
authors.initials: F
authors.lastname: Luberto
authors.affiliation: Rheumatology Unit, Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Arcispedale Santa Maria Nuova, Viale Risorgimento 80, 42123, Reggio Emilia, Italy.
authors.forename: Nicolò
authors.initials: N
authors.lastname: Pipitone
authors.affiliation: Rheumatology Unit, Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Arcispedale Santa Maria Nuova, Viale Risorgimento 80, 42123, Reggio Emilia, Italy. Electronic address: salvarani.carlo@asmn.re.it.
authors.forename: Carlo
authors.initials: C
authors.lastname: Salvarani
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D005260:Female; D014890:Granulomatosis with Polyangiitis / Q000453:epidemiology* / Q000401:mortality*; D006801:Humans; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012189:Retrospective Studies; D015996:Survival Rate
keywords: Northern Italy; epidemiology; granulomatosis with polyangiitis; mortality; population-based study