While very low disease activity standards in psoriatic arthritis (PsA) are stricter for the evaluation of remission status than Disease Activity Index for Psoriatic Arthritis (DAPSA) ≤4, there is a better correlation between DAPSA remission and the patient’s perspective of their disease, according to study data recently published in The Journal of Rheumatology.
This post hoc analysis included 227 participants (mean age, 52.0 to 53.7 years) from an observational, cross-sectional, retrospective, multicenter study in Spain. All participants met Classification for Psoriatic Arthritis criteria, had been treated with disease-modifying antirheumatic drugs (either synthetic or biological), underwent hand and foot radiologic tests within 6 months before the study visit, and had ≥1 year of disease history.
Very low disease activity was defined as meeting all 7 criteria for minimal disease activity. Remission scores were identified by DAPSA and clinical DAPSA scores ≤4. Quantitative variables were compared using Kruskall-Wallis H test, Mann-Whitney U test, or Student t test, while qualitative variables were compared using Fisher’s exact tests or Pearson chi-square tests.
Among the study’s participants, 28.6% (n=65) were in clinical DAPSA remission, 22.9% (n=52) were in DASPA remission, and 11.5% (n=26) had very low disease activity. Very low disease activity correlated moderately with clinical DAPSA (kappa=0.42) and DAPSA remission (kappa=0.52). The Psoriatic Arthritis Index of Disease (PsAID) measured a lower disease impact among those with very low disease activity (very low disease activity, 1.1±1.2; DAPSA remission, 1.3±1.5; clinical DAPSA remission, 1.7±1.6). Very low disease activity showed poor correlation with PsAID <4 (kappa=0.18). However, PsAID <4 correlated moderately with DAPSA (kappa=0.55) and clinical DAPSA (kappa=0.58) remission scores. In general, clinical DAPSA remission was associated with higher scores in all domains of the PsAID compared with very low disease activity.
The primary limitation to this study was a cross-sectional design, which showed only one moment in the disease duration.
The study researchers concluded that “in normal clinical practice, around 11% and 30% of patients with PsA achieve a [very low disease activity] or DAPSA remission state, respectively, which are associated with a low effect of disease (PsAID < 4). Cutaneous and musculoskeletal symptoms could exert different influences on the different PsAID items…[Very low disease activity] criteria seem to be more stringent for assessing a status of remission than are DAPSA ≤ 4. However, DAPSA ≤ 4 seems to better reflect the patients’ point of view of disease.”
This study received funding from Pfizer SLU. Certain authors report associations with Pfizer. See the reference for a full list of author disclosures.
Queiro R, Cañete JD, Montilla C, et al. Very low disease activity, DAPSA remission, and impact of disease in a Spanish population with psoriatic arthritis [published online February 1, 2019]. J Rheumatol. doi:10.3899/jrheum.180460