Psoriatic arthritis predicts psoriasis severity
MedWire News: Researchers have shown a clear link between psoriasis and arthritis severity in patients with psoriatic arthritis.
No such relationship has previously been established write Noemi Busquets-Pérez (Hospital General de Granollers, Spain) and co-workers in the journal Clinical Rheumatology.
"The majority of patients with psoriatic arthritis do manifest psoriasis during the course of arthritis," the authors add, "but the frequency of psoriatic arthritis among patients with psoriasis varies between 5% and over 40%."
To better understand the links between psoriasis and psoriatic arthritis, the researchers assessed data from 166 consecutive patients with both conditions who were treated by the same rheumatologists at appointments every 3-6 months.
Analysis revealed that psoriatic arthritis was significantly associated with more severe psoriasis, particularly in women. For example, 65.7% of patients had psoriatic nail disease, which was significantly predictive of psoriasis that was moderate-to-severe in intensity. Similarly, the presence of spondyloarthropathy was significantly correlated with moderate-to-severe psoriasis.
The authors could discern no links between severe psoriasis and age of psoriasis or arthritis onset, nor between severe psoriasis, arthritic involvement of distant joints, markers of arthritis severity, functional class, or disease activity score.
The investigators say their results are limited because patients were selected from a hospital population rather than from the general population. Because psoriatic arthritis can go undiagnosed for long periods, the patients in this study who were already diagnosed and receiving treatment may have represented a subset of patients with particularly aggressive disease. In addition, the cross-sectional nature of the study made it difficult to assess time-dependent events such as activity index, Busquets-Pérez et al say.
Nevertheless, the authors point out that the strong links between arthritis and moderate-to-severe psoriasis make it necessary for rheumatologists and dermatologists to collaborate on patient management. They suggest that rheumatologists may underestimate the impact of cutaneous disease on patient quality of life, and may not be familiar with standard tools for cutaneous disease evaluation.
MedWire (www.medwire-news.md) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2011
By Philip Ford