title: Prevalence of rheumatologist-diagnosed psoriatic arthritis in patients with psoriasis in European/North American dermatology clinics.
abstract: Prompt identification and treatment of psoriatic arthritis (PsA) in patients with psoriasis is critical to reducing the risk of joint damage, disability, and comorbidities.
  
  
  
  We sought to estimate PsA prevalence in patients with plaque psoriasis in 34 dermatology centers in 7 European and North American countries.
  
  
  
  Consecutive patients were evaluated by dermatologists for plaque psoriasis and subsequently by rheumatologists for PsA. PsA prevalence was estimated primarily based on rheumatologists' assessment of medical history, physical examination, and laboratory tests.
  
  
  
  Of 949 patients evaluated, 285 (30%) had PsA (95% confidence interval 27-33) based on rheumatologists' assessment. PsA diagnosis changed in 1.2% of patients when diagnostic laboratory tests were added to medical history and physical examination. Of 285 patients given the diagnosis of PsA, 117 (41%) had not been previously given the diagnosis.
  
  
  
  Bias may have been introduced by lack of standardized diagnostic criteria and unbalanced recruitment based on country populations.
  
  
  
  In this study, almost a third of patients with psoriasis seen in dermatology centers had PsA as determined by rheumatologists. More than a third of patients with PsA had not been previously given the diagnosis. Clinical evaluation alone is often sufficient basis for PsA diagnosis, but laboratory test results may be helpful in some patients.
authors: Swedish Medical Center, University of Washington School of Medicine, Seattle, Washington. Electronic address: pmease@philipmease.com.
authors: Philip J
authors: PJ
authors: Mease
authors: University of Toronto, Toronto, Ontario, Canada.
authors: Dafna D
authors: DD
authors: Gladman
authors: Probity Medical Research, Waterloo, Ontario, Canada.
authors: Kim A
authors: KA
authors: Papp
authors: Memorial University of Newfoundland, St John's, Newfoundland and Labrador, Canada.
authors: Majed M
authors: MM
authors: Khraishi
authors: Comprehensive Center for Inflammation Medicine, University of Lübeck, Lübeck, Germany.
authors: Diamant
authors: D
authors: Thaçi
authors: Comprehensive Center for Inflammation Medicine, University of Lübeck, Lübeck, Germany.
authors: Frank
authors: F
authors: Behrens
authors: Specialty Care, Pfizer Inc, Collegeville, Pennsylvania.
authors: Robert
authors: R
authors: Northington
authors: Specialty Care, Pfizer Inc, Collegeville, Pennsylvania.
authors: Joanne
authors: J
authors: Fuiman
authors: Specialty Care, Pfizer Inc, Collegeville, Pennsylvania.
authors: Eustratios
authors: E
authors: Bananis
authors: Specialty Care, Pfizer Inc, Collegeville, Pennsylvania.
authors: Robert
authors: R
authors: Boggs
authors: Specialty Care, Pfizer Inc, Collegeville, Pennsylvania.
authors: Daniel
authors: D
authors: Alvarez
mesh_terms: D015535:Arthritis, Psoriatic / Q000175:diagnosis* / Q000453:epidemiology* / Q000209:etiology; D003880:Dermatology; D005060:Europe; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011565:Psoriasis / Q000150:complications; D012219:Rheumatology; D014481:United States
keywords: assessment; dermatologist; diagnosis; laboratory test; prevalence; psoriasis; psoriatic arthritis; rheumatologist