HealthDay News — For patients with psoriatic arthritis (PsA), the age of psoriasis onset determines whether arthritis or psoriasis starts first, according to a study presented at the annual meeting of the American College of Rheumatology, held from Nov. 8 to 13 in Atlanta.
Umut Kalyoncu, M.D., from Hacettepe University in Ankara, Turkey, and colleagues examined the interrelationships among characteristics of skin psoriasis, arthritis, and arthritis timing among patients with PsA. A total of 1,631 patients were included: 71 had arthritis first, 309 had synchronous onset of arthritis and psoriasis, and 1,251 had psoriasis first.
The researchers found that age of psoriasis onset and not that of arthritis determined whether arthritis or psoriasis would appear first. When other independent variables were set to their baseline values, arthritis was delayed for 65 months after psoriasis. Pustular psoriasis correlated with arthritis onset about two years earlier than the intercept interval, while an increased delay from psoriasis to arthritis by about two years was seen for nail involvement, plaque psoriasis, or family history of psoriasis.
“PsA is a heterogeneous disease for clinical presentation and treatment response,” Kalyoncu said in a statement. “If patients with arthritis first are really a different subgroup, it means that treatment response and prognosis could be different from others. Indeed, in our cohort, achieving minimal disease activity is statistically less frequent in patients with arthritis first.”