Update on Psoriatic Arthritis: 3 New Things

Mar 06, 2018

What's new: reliable outcome measures, overlap in treatment targets, and immune checkpoint inhibitors.

1. Holland R, Tillett W, Korendowych E, et al. Validation of the Psoriatic Arthritis Impact of Disease (PsAID) Questionnaire and its potential as a single-item outcome measure in clinical practice. Ann Rheum Dis. 2018;77:343-347. doi: 10.1136/annrheumdis-2017-2119962. Van Mens LJJ, van de Sande MGH, van Kuijk AWR, et al. Ideal target for psoriatic arthritis? Comparison of remission and low disease activity states in a real-life cohort. Ann Rheum Dis. 2018;77. doi.org/10.1136/annrheumdis-2017-2119983. Kostine M, Rouxel L, Barnetche T, et al. Rheumatic disorders associated with immune checkpoint inhibitors in patients with cancer-clinical aspects and relationship with tumour response: a single-centre prospective cohort study. Ann Rheum Dis. 2018;77:393-398. doi: 10.1136/annrheumdis-2017-212257.

Highlights of 3 new studies in psoriatic arthritis include: (1) a new questionnaire measures outcomes; (2) a significant overlap exists in treatment targets between remission and low disease activity; and (3) rheumatic disorders associated with immune checkpoint inhibitors in patients with cancer respond well to therapy.^1-3 Scroll through the slides for the latest findings and take-home messages.
(©wavebreakmedia/Shutterstock.com)

A single-center cohort included 129 patients with psoriatic arthritis (mean age, 52.1 years) with mean disease duration of 10.2 years.¹

There was strong correlation with most of the patient-reported outcome measures (PROMS) of disease impact and moderate correlation with clinical outcomes with the PsAID score. There was also a strong correlation with individual PsAID items and their corresponding PROMS questionnaires.

"The good responsiveness of the PsAID and strong correlation of individual items with other PROMS represent an opportunity to reduce questionnaire burden for patients in studies and clinical practice," stated the researchers, led by Dr. Richard Holland of the Royal United Hospitals, Bath, United Kingdom.

A cross-sectional study of 250 patients with psoriatic arthritis evaluated various targets for remission and low disease activity. The results show very low disease activity was achieved by the smallest proportion of patients, which suggests that this stringent target could be difficult to obtain.²

Modified minimal disease activity measures were the most stringent targets for low disease activity in patients who achieved the target in terms of residual disease on joints, psoriasis, and enthesitis. The inclusion of C-reactive protein did not show an added value.

"It remains unknown whether meeting a strict target, such as very low disease activity, is superior in reducing impact on patient outcomes such as quality of life, radiographic progression and functioning, in comparison with less stringent targets," stated the researchers, led by Leonieke J. J. van Mens of University of Amsterdam, Amsterdam, The Netherlands.

Immune checkpoint inhibitors can cause a number of immune-related adverse events, including a variety of rheumatologic manifestations. A single-center, prospective, observational study included 524 patients who received immune checkpoint inhibitors; 35 patients were referred to the department of rheumatology (6.6%). All but one of the rheumatic immune-related adverse events occurred with anti-programmed death protein-1 or programmed death ligand-1 antibodies, with a median exposure time of 70 days.³

The two distinct clinical presentations included inflammatory arthritis (3.8%) mimicking rheumatoid arthritis (7 patients), polymyalgia rheumatica (11 patients), or psoriatic arthritis (2 patients); and non-inflammatory musculoskeletal conditions (2.8%, or 15 patients).

Inflammatory reactions were treated with glucocorticoids (19 patients) and methotrexate (2 patients). Non-inflammatory disorders were managed with NSAIDs, analgesics, and/or physiotherapy.

"All patients were responsive either to low-to-moderate doses of prednisone or symptomatic therapies and did not require immune checkpoint inhibitor discontinuation," stated the researchers, led by Dr. Marie Kostine of Universitaire de Bordeaux in Bordeaux, France. They noted that the tumor response was significantly higher in patients who experienced rheumatic immune-related adverse events.