title: Prevalence and incidence of systemic sclerosis in southern Sweden: population-based data with case ascertainment using the 1980 ARA criteria and the proposed ACR-EULAR classification criteria.
abstract: OBJECTIVE
  To estimate the prevalence and incidence of systemic sclerosis (SSc) in southern Sweden.
  
  
  METHODS
  In Skåne, the southernmost region of Sweden (total population 1.2 million), healthcare provided is registered in the Skåne Healthcare Register. We identified all Skåne residents who had received an International Classification of Diseases 10 diagnosis of SSc (M34) or Raynaud's phenomenon (I73.0) between 1998 and 2010. Every single case was ascertained by review of medical records in reference to the 1980 American Rheumatism Association preliminary classification criteria for SSc and the proposed American College of Rheumatology (ACR)-European League Against Rheumatism (EULAR) classification criteria presented at the ACR/Association of Rheumatology Health Professionals Annual Meeting 2012. We calculated the point prevalence by the end of 2010 by linkage with the population register to exclude deceased persons and we also estimated the mean annual cumulative incidence for 2006-2010.
  
  
  RESULTS
  Using the 1980 ARA criteria, the adult prevalence and annual incidence of SSc in the Skåne region were 235 and 14 per 1 million inhabitants respectively. Applying the proposed ACR-EULAR criteria, the corresponding figures were 305 and 19 per 1 million inhabitants. A majority (82%) of the prevalent cases had the limited cutaneous SSc subtype.
  
  
  CONCLUSIONS
  The prevalence and incidence of SSc in southern Sweden, based on the 1980 ARA criteria, are higher than previously reported in northern Europe and do not support the concept of a north-south gradient of SSc occurrence in Europe. Application of the proposed ACR-EULAR classification criteria in this population results in about 30-40% higher estimates of SSc prevalence and incidence compared to the 1980 ARA criteria.
authors.affiliation: Department of Clinical Sciences Lund, Section of Rheumatology, Lund University, Lund, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Andréasson
authors.affiliation: Department of Clinical Sciences Lund, Section of Rheumatology, Lund University, Lund, Sweden.
authors.forename: T
authors.initials: T
authors.lastname: Saxne
authors.affiliation: Epi-centre Skåne, Skåne University Hospital, Lund, Sweden Department of Orthopedics, Clinical Sciences Lund, Lund University, Lund, Sweden.
authors.forename: C
authors.initials: C
authors.lastname: Bergknut
authors.affiliation: Department of Clinical Sciences Lund, Section of Rheumatology, Lund University, Lund, Sweden.
authors.forename: R
authors.initials: R
authors.lastname: Hesselstrand
authors.affiliation: Epi-centre Skåne, Skåne University Hospital, Lund, Sweden Department of Orthopedics, Clinical Sciences Lund, Lund University, Lund, Sweden Clinical Epidemiology Research and Training Unit, Boston University, Boston, Massachusetts, USA.
authors.forename: M
authors.initials: M
authors.lastname: Englund
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D001323:Autoantibodies / Q000097:blood; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012042:Registries; D012595:Scleroderma, Systemic / Q000175:diagnosis / Q000453:epidemiology* / Q000276:immunology; D012720:Severity of Illness Index; D017678:Sex Distribution; D013548:Sweden / Q000453:epidemiology
chemical_list: D001323:Autoantibodies
keywords: Autoimmune Diseases; Epidemiology; Systemic Sclerosis