Expert Consensus on a Set of Outcomes to Assess the Effectiveness of Biologic Treatment in Psoriatic Arthritis: The MERECES Study

Objective. To reach a consensus on the instruments to be used in clinical practice to evaluate the effectiveness of biological disease-modifying antirheumatic drug (bDMARD) treatment in patients with psoriatic arthritis (PsA) in the short to medium term (3-6 mos), and to establish the minimum health outcomes for treatment continuation. Methods. A 2-round Delphi questionnaire was developed based on both the information gathered in the literature review and 4 discussion groups. The suitability and feasibility of the proposed sets of instruments were assessed on a 7-point Likert scale. Consensus was established when at least 75% of healthcare professionals (HCP) reached agreement. To define a minimum health outcome to continue treatment, a combination of 4 disease activity states and 3 health-related quality of life states were defined for 3 hypothetical patient profiles. HCP were given a dichotomous choice ( yes/no) to respond to whether they would continue treatment in each case. Results. The second round was completed by 106 HCP. Consensus was reached on the use of (1) Disease Activity in Psoriatic Arthritis + Psoriatic Arthritis Impact of Disease (PsAID12) or minimal disease activity + PsAID12 + C-reactive protein, in peripheral PsA; and (2) Ankylosing Spondylitis Disease Activity Score + PsAID12, in axial PsA. Health outcomes considered sufficient to continue treatment were stricter for bDMARD-naive patients than for patients who failed several bDMARD. Conclusion. To the best of our knowledge, this is the first multidisciplinary consensus on a set of outcomes for the evaluation of bDMARD effectiveness in PsA, in routine clinical practice.