title: Epidemiology of chronic spontaneous urticaria: results from a nationwide, population-based study in Italy.
abstract: BACKGROUND
  Chronic spontaneous urticaria (CSU) is a common skin disease, but there is a paucity of precise epidemiological data on this disease.
  
  
  OBJECTIVE
  To obtain information on the epidemiology of CSU in Italy.
  
  
  METHODS
  The data source was the Health Search IMS Health Longitudinal Patient Database. The study population was formed by patients aged ≥ 15 years, registered with a total of 700 general practitioners, homogeneously distributed across Italy. An algorithm based on the International Classification of Diseases, ninth revision, Clinical Modification was used for the identification of patients with CSU. The annual prevalence and incidence rates of CSU over a 12-year period (2002-2013) were estimated, along with demographic and clinical determinants.
  
  
  RESULTS
  The annual prevalence of CSU ranged from 0·02% in 2002 to 0·38% in 2013. The incidence was 0·10-1·50 per 1000 person-years. For both prevalence and incidence rates, female patients outnumbered male. The risk of CSU was statistically significantly higher in the presence of the following variables: obesity; anxiety, dissociative and somatoform disorders; malignancies; use of immunosuppressive drugs; and chronic use of systemic corticosteroids. History of autoimmune thyroiditis showed a trend towards an increased risk of CSU, though it was not statistically significant. Smoking was associated with a significantly reduced risk of CSU.
  
  
  CONCLUSIONS
  Our findings on CSU prevalence are consistent with those obtained in previous studies. Furthermore, this large population-based study provides important information regarding the association of CSU with demographic and clinical determinants, which have been examined in the primary-care setting.
authors.affiliation: Health Search, Italian College of General Practitioners and Primary Care, Florence, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Lapi
authors.affiliation: Dermatology and Venereology Private Practice, Bari/Barletta, Italy.
authors.forename: N
authors.initials: N
authors.lastname: Cassano
authors.affiliation: IMS Health Information Solutions Srl, Milan, Italy.
authors.forename: V
authors.initials: V
authors.lastname: Pegoraro
authors.affiliation: IMS Health Information Solutions Srl, Milan, Italy.
authors.forename: N
authors.initials: N
authors.lastname: Cataldo
authors.affiliation: IMS Health Information Solutions Srl, Milan, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Heiman
authors.affiliation: Health Search, Italian College of General Practitioners and Primary Care, Florence, Italy.
authors.forename: I
authors.initials: I
authors.lastname: Cricelli
authors.affiliation: Health Search, Italian College of General Practitioners and Primary Care, Florence, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Levi
authors.affiliation: Novartis Farma S.p.A., Origgio, Varese, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Colombo
authors.affiliation: Novartis Farma S.p.A., Origgio, Varese, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Zagni
authors.affiliation: Italian College of General Practitioners and Primary Care, Florence, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Cricelli
authors.affiliation: Dermatology and Venereology Private Practice, Bari/Barletta, Italy.
authors.forename: G A
authors.initials: GA
authors.lastname: Vena
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D017678:Sex Distribution; D014581:Urticaria / Q000453:epidemiology* / Q000209:etiology; D055815:Young Adult