Background/Purpose: Previous analyses have identified enrolment year as an independent predictor of real-world retention on anti-TNF treatment whereby patients enrolled in later periods were more likely to be switched. The aim of this analysis was to compare between enrolment periods for psoriatic arthritis (PsA) treatment outcomes and frequency of treating to target, and to assess the impact of target type on long-term function.

Methods: This is a post-hoc analysis of data from the Biologic Treatment Registry Across Canada (BioTRAC). Patients were grouped into enrolment periods: 2005-2008, 2009-2012, 2013-2015, 2016-2017. Achievement of MDA (5/7 of: TJC28≤1, SJC28≤1, PASI≤1, pain≤15mm, PtGA≤20mm, HAQ≤0.5, tender entheseal points≤1), VLDA (7/7 criteria), and sustained MDA or VLDA (at 6 and 12 months) were compared between enrolment periods with the Chi-square test. The impact of achieving MDA or VLDA at 6 months, 12 months, or both (sustained) on HAQ-DI at 18 months was assessed with one-way ANOVA and generalized linear models.

Results: 392 PsA patients treated with anti-TNFs (IFX: n=111; GLM: n=281) were included. Across enrolment periods, a significant increase in baseline age (48.5 vs. 50.3 vs. 51.9 vs. 54.8 years; p=0.021) was observed. At 6 and 12 months, 44.2% and 45.6% achieved MDA, 18.4% and 19.9% achieved VLDA, while 36.8% and 13.2% achieved sustained MDA and VLDA, respectively, without significant differences across enrolment periods.

Among patients not achieving LDA at 6 and 12 months, an intervention was applied in 40-45% of patients, without significant differences between enrolment periods. Between 6 and 12 months, the most common intervention was anti-TNF discontinuation (71.2% of non-LDA achievers), followed by DMARD addition (12.1%), DMARD dose increase (7.6%) or NSAID addition (7.6%). Similar results were obtained post 12 months.

Patients achieving sustained MDA, followed by those achieving MDA either at 6 or 12 months had significantly lower HAQ at 18 months compared to patients not achieving MDA at either timepoint (0.2 vs. 0.6 vs. 1.2; p< 0.001). Similar results were observed when evaluating achievement of remission albeit with greater impact on HAQ at 18 months (0.1 vs. 0.2 vs. 0.9; p< 0.001). Adjustment for baseline HAQ did not impact the results.

Conclusion: Target achievement among PsA patients has remained stable over time with relatively infrequent regimen optimization prior to anti-TNF discontinuation. Achieving stricter targets was associated with greater benefits in terms of long-term patient function.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/application-of-treat-to-target-and-impact-of-sustained-low-disease-activity-or-remission-on-function-in-psoriatic-arthritis-patients/