Risk Factors Associated with Difficult-to-treat (D2T) Psoriatic Arthritis - A One-year Analysis from the APLAR SpA Registry

Background: Despite the widespread advocacy of the treat-to-target(T2T) strategy for managing psoriatic arthritis (PsA), a significant number of patients fail to achieve minimal disease activity (MDA) even with advanced therapies. While a universal definition of difficult-to-treat(D2T) PsA is absent, investigating the heterogeneity of D2T PsA within a real-life T2T-cohort can offer valuable insights into comprehending this concept. Methods: This analysis included the first 111 PsA patients enrolled in the APLAR SpA registry who underwent 1-year T2T management. They were recruited from 6 Asia-Pacific regions. D2T was defined as the failure to achieve MDA despite receiving [Formula: see text]1 conventional synthetic disease-modifying anti-rheumatic drugs(csDMARDs) and [Formula: see text]1 biologic/targeted synthetic DMARDs(b/tsDMARDs) over 6-months. Results: A total of 111 patients (mean age: 48± 13 years, 59 [53%] male, mean disease duration: 5.3± 7.3 years) were included. At baseline, the patients exhibited moderate disease activity, with only 35% achieving MDA. After 1-year, a significant improvement in Disease Activity in Psoriatic Arthritis (DAPSA) was observed (16.3± 14.0 at baseline vs 10.1± 9.7 at 1-year, p