Background In clinical practice we often extrapolate experience and evidence from patients with RA to patients with PsA. The body of evidence supporting the use of csDMARD co-medication in PsA patients treated with bDMARDs is weak.
Objectives Our aim was to determine whether co-medication with csDMARDs has an impact on the retention of bDMARDs in PsA.
Methods In December 2015 we extracted data of patients with PsA treated with the first bDMARD with at least one follow-up visit from the mandatory national registry BioRx.si. Appropriate descriptive statistics methods were used to describe the cohort. Where applicable appropriate post hoc tests were used to compare the baseline characteristics. We used the unadjusted Kaplan-Meier method with log rank test as the post hoc test to assess the retention of the bDMARDs depending on co-medication with csDMARDs (i.e. methotrexate or leflunomide or sulfasalazine).
Results At the time of extraction 276 (44% female) patients with a median (IQR) age of 49.5 (42.0–56.6) years treated for 733 person years satisfied the inclusion criteria. Median follow-up time was 1.5 years (0.6–3.2) years. 50%/20%/18%/12% were treated with adalimumab/etanercept/golimumab/infliximab, respectively. Methotrexate/leflunomide/sulfasalazine were predominantly used as co-medication in 70%/9%/5% of patients while 16% never received csDMARD co-medication. There was no significant difference in the retention of the initial bDMARD depending on csDMARD use at the initiation of the bDMARD or when the csDMARD was used on <50% of follow-up visits. However, the bDMARD retention was significantly longer when csDMARD was used on more than 80% of follow-up visits (p=0.005; Figure 1).
Conclusions Regular co-medication with csDMARDs seems to improve the retention of the first line bDMARDs in PsA in daily clinical practice.
Disclosure of Interest None declared