Demographic characteristics and health-related quality of life of patients with moderate-to-severe psoriasis: The VACAP study

Background: Psoriasis is associated with a deterioration in the health-related quality of life (HRQoL) of affected patients. The aim of this study was to assess the HRQoL of patients with moderate-to-severe psoriasis.

Methods: A prospective observational study (the VACAP Study) was carried out in 123 centers in Spain with 1217 patients. Patients were evaluated at baseline (visit 1 [V1]) and again four months later (visit 2 [V2]). The severity of psoriasis was determined using the following indices: (i) Psoriasis Area and Severity Index (PASI) (score range 0-72, higher score indicates more severe disease), (ii) the body surface area (BSA) affected, and (iii) the Physicians Global Assessment (PGA) (range 1-7, higher score indicates more severe disease). Four questionnaires were used for the assessment of the HRQoL: (i) the Short-Form 36 quality-of-life questionnaire (SF-36) (score range 0-100, higher score indicates better HRQoL); (ii) Euroqol (EQ-5D) (range from 1 to 3, lower score indicates better HRQoL); (iii) Dermatology Life Quality Index (DLQI) (ranges 0-30; from best to worst HRQoL); and (iv) Psoriasis Disability Index (PDI) (ranges 0-45; higher score indicates better HRQoL).

Results: The mean (SD) age of the patients was 45.11 (13.92) years at V1. The mean age at the onset of psoriasis was 26.08 (14.19) years. The majority of patients were female (61%) and were employed (68%). The mean PASI score was 13.24 (9.50) at V1 and 5.07 (6.03) at V2 (P<.001). Scores from the generic HRQoL questionnaires (EQ-5D, SF-36) showed significant improvement between visits in all dimensions measured (P<.001). The disease-specific questionnaires also revealed overall improvements in quality of life over time: the DLQI mean total score was 8.97 (7.28) at V1 and 4.76 (5.72) at V2 (P<.001), and the PDI mean total score was 9.24 (8.76) V1 and 4.88 (6.65) at V2 (P<.001). Multivariate analysis using PDI as the dependent variable showed that the principal factors related to HRQoL were severity of psoriasis as measured by PASI (P<.001), and gender (P=.048).

Conclusions: The principal factor related to HRQoL in patients with psoriasis is the severity of the disease.