Comparing Burden of Psoriatic Arthritis With Different Definitions of Disease Activity

In patients with early psoriatic arthritis (PsA) with low disease activity, burden of disease was similar in patients achieving minimal disease activity (MDA) and patients attaining the Disease Activity Index for PsA-Low Disease Activity (DAPSA-LDA) in usual care, according to the results of a real-life cohort study published in Arthritis Care & Research.

The investigators sought to compare the burden of PsA in patients with low disease activity according to the 2 definitions, MDA and DAPSA-LDA, after 1 year following diagnosis. Data were collected on MDA, DAPSA-LDA, and disease burden from patients included in the Dutch southwest Early Psoriatic Arthritis cohort. Burden of disease was assessed in 2 domains:  “body functions,” including Short Form 36 Bodily Pain (SF36-BP); and “activity,” including the Health Assessment Questionnaire (HAQ).

A total of 292 patients were enrolled in the study; 48% achieved MDA and 64% achieved DAPSA-LDA. Mean patient age was 51±14 years and 51% of the participants were men. Median symptom duration prior to diagnosis was 12 months.

The average body function and activity domains were similar in participants in MDA and participants in DAPSA-LDA. Scores were significantly improved in 44% of patients in both MDA and DAPSA-LDA compared with 20% of patients only in DAPSA-LDA.

Average SF36-BP was significantly higher in participants who attained both targets (74.7; 95% CI, 72.0-77.4) compared with participants who only attained DAPSA-LDA (58.7; 95% CI, 54.8-62.6). Likewise, mean HAQ scores were 0.19 (95% CI, 0.14-0.25) and 0.61 (95% CI, 0.48-0.73), respectively.

The investigators concluded that although average disease burden was similar in participants in MDA and participants in DAPSA-LDA, participants who attained only DAPSA-LDA reported worse outcomes compared with participants who also attained MDA. Moreover, MDA was more difficult to achieve.

Reference

Wervers K, Vis M, Tchetverikov I, et al. Burden of psoriatic arthritis in different definitions of disease activity: comparing minimal disease activity and disease activity index for psoriatic arthritis [published online April 2, 2018]. Arthritis Care Res (Hoboken). doi:10.1002/acr.23571