Assessment of the Patient Acceptable Symptom State (PASS) in psoriatic arthritis: association with disease activity and quality of life indices

OBJECTIVE: The aim of this study was to evaluate the discriminant capability of the Patient Acceptable Symptom State (PASS) according to disease activity, remission/low disease activity indices and quality of life indices in patients with psoriatic arthritis (PsA). METHODS: Consecutive patients with PsA were enrolled in this cross-sectional study. At each visit, the patients underwent a complete physical examination and their clinical/laboratory data were collected. Disease activity was assessed using the Disease Activity Score for Psoriatic Arthritis (DAPSA) and remission/low disease activity using the DAPSA minimal disease activity (MDA) and very low disease activity (VLDA) criteria. The Psoriatic Arthritis Impact of Disease (PsAID) and the Health Assessment Questionnaire-Disability Index scores were also collected. Finally, PASS was assessed by asking all patients to answer yes or no to a single question. RESULTS: Patients who answered yes to PASS showed a significantly better overall mean DAPSA score than those who were not in PASS. Furthermore, patients in PASS showed a significantly lower level of systemic inflammation, lower Leeds Enthesitis Index score, a significantly lower impact of disease (PsAID), lower pain and better function than patients who answered no to PASS. A moderate to good agreement was found between PASS, MDA, DAPSA low disease activity and PsAID score ≤4. Good sensitivity and specificity were found with PASS with respect to DAPSA low disease activity, and although PASS is sensitive in the identification of patients with MDA, DAPSA remission and VLDA it lacks of specificity. DISCUSSION: This study showed that PASS might be used as an alternative to determine disease activity in patients with PsA in real clinical practice, mainly in patients with low disease activity according to DAPSA criteria.