Subclinical psoriatic arthritis: concepts, dilemmas, and research needs

Psoriatic arthritis (PsA) develops in up to one-third of patients with psoriasis (PsC), yet increasing attention is now focused on a putative subclinical phase preceding overt arthritis. Several conceptual frameworks describe the PsC-PsA transition, including the pragmatic definition proposed by the European Alliance of Associations for Rheumatology, which defines subclinical PsA as arthralgia and/or imaging abnormalities in the absence of clinical synovitis. However, the absence of validated serological biomarkers, the marked clinical heterogeneity of PsA, the frequent occurrence of nonspecific musculoskeletal symptoms, and the limited specificity of imaging findings complicate risk stratification and may lead to misclassification and overtreatment. Lessons from rheumatoid arthritis highlight both the potential and the pitfalls of applying prevention paradigms to subclinical disease. This viewpoint critically appraises current definitions of subclinical PsA, discusses therapeutic and trial-design implications, and outlines key research priorities, including longitudinal PsC cohorts, advanced and molecular imaging, and multiomic biomarker discovery. Future progress depends on developing robust risk-stratification models that capture the full spectrum of psoriatic disease and enable targeted prevention strategies while minimising unnecessary intervention. At the same time, caution is warranted against broad expansion of the 'subclinical' disease state concept, as it may dilute disease definitions, increase overdiagnosis, and divert attention from improving early and accurate identification of clinically meaningful PsA.