title: Relationship between psoriasis severity, clinical symptoms, quality of life and work productivity among patients in the USA.
abstract: BACKGROUND
  Psoriasis is a chronic disease, and many patients experience itching, painful skin and scaling. The relationship between psoriasis severity and symptom severity, quality of life (QoL) and work productivity is not fully understood.
  
  
  OBJECTIVE
  To examine how QoL, work productivity and clinical symptoms vary between patients with mild, moderate and severe psoriasis.
  
  
  METHODS
  During a recent US survey, dermatologists provided information on overall disease severity, symptom severity and comorbidities. Patients with psoriasis completed QoL and work productivity instruments: the EuroQoL 5-Dimension Health (EQ-5D) questionnaire, the Dermatology Life Quality Index (DLQI), and the Work Productivity and Activity Impairment (WPAI) questionnaire. Multivariate regression was used to explore the relationship between these outcome variables and psoriasis severity, controlling for differences in demographics and comorbidities.
  
  
  RESULTS
  The study analysed 694 patients (55% male; mean age: 44 years); 48%, 46% and 6% had mild, moderate and severe psoriasis, respectively. Scaling was the most common symptom, which was experienced by 82% of patients, followed by itching (73%) and pain (32%). Increased psoriasis severity was associated with increased itching, pain and scaling, and with reduced QoL (decrease in EQ-5D scores: moderate vs. mild -0.04, severe vs. mild -0.18; increase in DLQI: moderate vs. mild 2.97, severe vs. mild 7.95). WPAI scores increased with severity, indicating greater impairment (moderate vs. mild: 11.77, severe vs. mild 18.73).
  
  
  CONCLUSIONS
  Patients with more severe psoriasis experienced more severe symptoms and had a greater reduction in QoL and work productivity. It is important that physicians recognize the impact of severe disease on patients' lives and take steps to address this.
authors.affiliation: Clinical Trials Unit, University Hospitals Case Medical Center, Cleveland, OH, USA.
authors.forename: N J
authors.initials: NJ
authors.lastname: Korman
authors.affiliation: Novartis Pharmaceuticals Corporation, East Hanover, NJ, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Adelphi Real World, Macclesfield, UK.
authors.forename: J
authors.initials: J
authors.lastname: Pike
authors.affiliation: Adelphi Real World, Macclesfield, UK.
authors.forename: J
authors.initials: J
authors.lastname: Roberts
mesh_terms: D000328:Adult; D000368:Aged; D004526:Efficiency; D004651:Employment; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000523:psychology; D011537:Pruritus / Q000523:psychology; D011565:Psoriasis / Q000150:complications* / Q000523:psychology*; D011788:Quality of Life; D012044:Regression Analysis; D012189:Retrospective Studies; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D014481:United States