Poor Treatment Response Linked to Residual Disease in Patients with PsA

There is an unmet need for more effective treatments, optimization, and refinement of treatment strategies to minimize residual disease in patients with psoriatic arthritis (PsA) who have not yet achieved treatment goals, as well as those who have already obtained them, according to a study published in Springer.¹

“Although the achievement of treatment targets has been associated with improved quality of life and slower disease progression, patients may still experience symptoms and a burden of disease,” investigators stated. “This applies even for the most stringently defined recommending remission (REM) by the minimal disease activity (MDA) metric, very low disease activity (VLDA), and residual disease is likely greater among patients achieving less stringent forms of REM by other disease activity metrics.”

The databases MEDLINE, Embase, and the Cochrane Database of Systemic Reviews (CDSR) were utilized to search for the terms “PsA,” “treatment targets,” and “observational studies” in this systemic literature review (SLR). Investigators focused on adult patients with PsA who have received treatment and were assessed with treat-to-target metrics, such as the Disease Activity Index in PsA (DAPSA) and MDA. Studies that collected residual disease outcomes in this patient population who had received at least 1 pharmacological treatment were included.

Out of 2328 articles, 27 studies were included in the review, with 23 reporting information on MDA-assessed patients and 14 focusing on DAPSA-assessed patients. Twenty-one studies were cross-sectional in design and 6 were longitudinal.

While residual disease, reported from both physicians and patients, was less frequent and/or severe in patients who achieved targets, it was not absent, even for those achieving VLDA or remission. Between 0-8% of patients in remission had > 1 tender joints, 25-39% had a Psoriasis Area and Severity Index (PASI) score of > 1, and 0-19% had patient-reported pain of >15.

Residual disease was less frequent and/or less severe among those who obtained MDA-assessed targets when compared with DAPSA-assessed targets, particularly for skin outcomes (reported in 14 studies) (19-34% vs 22-42%, respectively).

Patient-reported outcomes, including fatigue, quality of life, and disability, were analyzed using the Psoriatic Arthritis Impact of Disease 12-item questionnaire (PsAID-12). For patients who did not achieve either MDA or DAPSA/clinical DAPSA low disease activity (cDAPSA LDA), the mean PsAID-12 ranged from 3.8 to 7.1 and 3.9 to 5.3, respectively. However, those who obtained MDA scored between 1.1 and 3.5 and those who achieved at least DAPSA/cDAPSA LDA had scores ranging from 1.7 to 2.7.

Best-practice systematic review methods were adhered to and investigators only chose studies that covered a variety of regions and populations. However, the observational nature of the study was limiting due to differences in study design, patient characteristics, and treatment. Further, as most studies were cross-sectional, patients were not assessed at a specific timepoint within treatment and disease duration. Therefore, some patients may have had less time on treatment and less of an opportunity for a disease response. Results were complicated by prevalence and severity being reported in different ways across studies.

“Future studies should aim to evaluate whether patients’ perceptions of their symptoms and disease, and their knowledge and expectations of available treatments and outcomes, may affect the burden of disease they experience,” investigators concluded. “This may ultimately help advance patient education and engagement and tailoring of treatment strategies to address the aspects of PsA that are of greatest importance to patients.”

Reference:

Coates LC, de Wit M, Buchanan-Hughes A, Smulders M, Sheahan A, Ogdie AR. Residual Disease Associated with Suboptimal Treatment Response in Patients with Psoriatic Arthritis: A Systematic Review of Real-World Evidence [published online ahead of print, 2022 Apr 12]. Rheumatol Ther. 2022;10.1007/s40744-022-00443-y. doi:10.1007/s40744-022-00443-y