The new publication will help to define the clinical and imaging features of people with psoriasis who should raise clinical suspicion for progression to PsA.

New EULAR points-to-consider characterize the transition from skin to joint involvement in psoriatic disease.

Overall, five overarching principles and 10 points-to-consider were formulated by a multidisciplinary task force of 30 members from 13 European countries. The principles acknowledge that people with psoriasis may develop psoriatoic arthrotos (PsA) at different times – or not at all – and highlight that there is a need for close collaboration between dermatologists and rheumatologists – although the rheumatologist has a key role in PsA diagnosis and management. 

They also stress that being able to identify risk factors for PsA may influence therapy choices in people with psoriasis, especially since certain systemic treatments for psoriasis may reduce the risk of transition to PsA.

The points-to-consider highlight arthralgia and abnormalities seen on ultrasound or magnetic resonance imaging as key elements of subclinical PsA that can potentially be used as short-term predictors of who will go on to develop PsA. This also makes these elements useful to help design clinical trials looking at PsA interception and prevention. Traditional risk factors for PsA development such as psoriasis severity, obesity and nail involvement may represent more long-term disease predictors. As such, these are felt to be less useful for short-term trials investigating the transition from psoriasis to PsA.

The task force also proposed some standard naming for three distinct stages in PsA development. Firstly, people with psoriasis at higher risk of PsA, then people with subclinical PsA, and then people with clinical PsA. This has been shown in other inflammatory rheumatic musculoskeletal diseases that clinical onset is preceded by a preclinical phase where a person has arthralgia and immunological or imaging abnormalities, in the absence of a clinical diagnosis. The task force also proposed a definition for early PsA based on the development of joint swelling as a clinical outcome measure for trials of PsA prevention.

They also hope it can be used to identify people who could benefit from a therapeutic intervention to delay or prevent PsA. In the meantime, people with psoriasis should be informed about the risk of developing PsA and encouraged to report their symptoms to facilitate early PsA recognition.

The points-to-consider appear in the June 2023 issue of the Annals of the Rheumatic Diseases.