Discovery of Psoriatic Arthritis in Psoriasis Patients for Early Rheumatological Referral (DAPPER) Study: A Prospective Observational Cohort

Patients with psoriasis are at risk of developing psoriatic arthritis, which can lead to irreversible joint damage. However, a proportion of patients with psoriasis and concomitant psoriatic arthritis remain undiscovered in practice. The aims of this study were: to prospectively determine prevalence, characteristics, and disease burden of psoriatic arthritis in a psoriasis population; and to determine the prevalence and characteristics of patients with active psoriatic arthritis, who were not under rheumatological care. Patients with psoriasis were screened by a rheumatologist at the dermatology outpatient clinic for psoriatic arthritis. Patients with suspected active psoriatic arthritis who were not seeing a rheumatologist were referred to a rheumatologist for confirmation. The total prevalence of psoriatic arthritis in this observational, prospective cohort (n = 303) was 24%. Patients with psoriasis with concomitant psoriatic arthritis had longer duration of skin disease and more often a treatment history with systemic therapies. In this academic, specialized, setting, 2.3% of patients (n = 7), were not receiving rheumatological care despite having active psoriatic arthritis. These patients were characterized by a combination of low (perceived) disease burden and low yield of screening questionnaires, making it difficult for dermatologists to discover psoriatic arthritis in these patients. Thus, screening for more subtle active arthritis in patients with psoriasis in a dermatology setting could be improved.