Editorial board comment
The 2012 recommendations for treating spondyloarthritis (SpA) to target were largely based on expert opinion. In the intervening years, some progress had been achieved in particular with the publication of the first Treat-to-Target (T2T) strategy trial in Psoriatic Arthritis (PsA), the TICOPA study . In addition, there had been a number of publications on the target for treatment both in psoriatic arthritis (PsA) and in axial SpA. Thus, the 2017 T2T recommendations and discussions reflect this progress though the research agenda now contains some additional and important items.
Unresolved is the issue of the inclusion of all domains of disease in the remission definition, in particular in PsA. There are those who argue for a more restricted definition focusing on joint involvement in PsA whilst acknowledging that other domains of involvement such as skin psoriasis need to be assessed but separately. Then there are those who argue equally strongly that a PsA patient needs to be viewed and measured in all of the ways that the psoriatic disease affects them as otherwise the “silo” approach to the management of PsA persists, with rheumatologists only “seeing” the musculoskeletal disease and dermatologists only “seeing” the skin and nail involvement. Patients do not leave their skin or their joints at the door when coming to see their specialist.
The 2017 recommendations are different in that there are now 11 recommendations for SpA with no separate recommendations for axial SpA, PsA or peripheral SpA deemed necessary. Many of the individual recommendations are similar to those made in 2012 but there are some notable changes.
For axial SpA, the Ankylosing Spondylitis Disease Activity Score (ASDAS) is now included as the preferred assessment tool for disease activity. For PsA, both Minimal Disease Activity (MDA) and Disease Activity in PSoriatic Arthritis (DAPSA) are explicitly mentioned as ways of defining the target, although other instruments such as CPDAI, GRACE and PASDAS are not discounted.
Other subjects of discussion included the importance or otherwise of including C-reactive protein (CRP) in assessing disease activity in PsA as well as whether a measure of function, such as the Health Assessment Questionnaire (HAQ), should be included.
CRP is included in some of the composite measures but may not contribute much to the assessment of PsA disease activity in many patients with active disease. The HAQ may be both a reflection of inflammation and of damage. One could argue that HAQ may not change in late disease where there is considerable joint damage. However, cohort studies would suggest that it is mainly pain, rather than HAQ, that does not change in assessing MDA. Clearly these are issues for further debate following progress with the research agenda in 5 years’ time.
1. Coates LC, Moverley AR, McPartland L et al. Effect of tight control of inflammation in early psoriatic arthritis (TICOPA): a UK multicentre, open-label, randomised controlled trial. Lancet 2015; 386: 2489–98.