Very Low Disease Activity, DAPSA Remission, and Impact of Disease in a Spanish Population with Psoriatic Arthritis

Objective. To examine the grade of agreement between very low disease activity (VLDA) and Disease Activity Index for Psoriatic Arthritis (DAPSA) remission, as well as their association with the effect of the disease as assessed by the Psoriatic Arthritis Impact of Disease (PsAID) questionnaire in patients with psoriatic arthritis in routine clinical practice. Methods. Posthoc analysis of data from a cross-sectional multicenter study. Patients were included who fulfilled the Classification for Psoriatic Arthritis (CASPAR) criteria with at least 1 year of disease duration and were treated with biological and/or conventional synthetic disease-modifying antirheumatic drugs according to routine clinical practice in Spain. Patients were considered in VLDA if they met 7/7 of the minimal disease activity criteria. DAPSA and clinical (c) DAPSA score <= 4 identified remissions. Results. Of the 227 patients included in the original study, 26 (11.5%), 52 (22.9%), and 65 (28.6%) were in VLDA, DAPSA remission, and cDAPSA remission, respectively. There was a moderate agreement between VLDA and DAPSA remission (kappa = 0.52) or cDAPSA remission (kappa = 0.42). Patients with VLDA had less effect of the disease as measured by PsAID [mean total score (SD): VLDA 1.1 (1.2); DAPSA remission 1.3 (1.5); cDAPSA remission 1.7 (1.6)]. There was a moderate agreement between DAPSA remission or cDAPSA remission and PsAID < 4 (kappa = 0.46 and kappa = 0.58 respectively), while poor agreement (kappa = 0.18) was found between VLDA and PsAID < 4. Conclusion. VLDA criteria seem to be more stringent for assessing a status of remission; however, DAPSA remission shows better correlation with a patient-acceptable symptoms state than VLDA does.