Background Biologic therapies have significantly improved outcomes for patients with rheumatoid arthritis (RA), but concern remains regarding the occurrence of rare adverse events. Under the auspices of EULAR, a study group of investigators representing European Biologic Registers was convened in 2012. The remit was to explore an approach to combined analysis for rare biologic-associated adverse events, as it was recognised that individually, no single register may have sufficient power to explore these events alone.
Objectives The purpose of this initial analysis was to compare the baseline characteristics of patients starting a first biologic therapy across Europe and to identify a common initial dataset.
Methods 17 registers across Europe were invited to participate and data from 12 are included in this initial analysis. Baseline characteristics of patients starting their first biologic between 01/01/2008 and 31/12/2008 were collected including demographics, disease and drug characteristics and comorbidities.
Results In total, 4573 patients with RA initiating a first ever biologic were included from 12 registers across Europe (1676 ETN, 810 IFX, 1646 ADA, 9 ANA, 64 ABA, 349 RTX, 5 TCZ, 14 other). In 2008, almost half of the registers had limited recruitment restricted to certain biologics only. All registers collected age, gender, disease duration, seropositivity for IgM-RF, DAS28, concurrent MTX and corticosteroid use (Table 1). Less frequent items included physician global score and patient pain and fatigue. Disease severity varied across the registers with DAS28 ranging from 4.2 to 6.6 and HAQ ranging from 0.8 to 1.9. Steroid use ranged from 13 to 72%. Seven registries reported on comorbidity, with hypertension being the most frequent. The prevalence of comorbidities was relatively constant across the registers with the exception of depression, which ranged from 1.4% to 20.1%.
Conclusions This initial exercise has been a success with respect to a European-wide collaboration of rheumatology biologic registers. It has identified differences in prescribing patterns, recruitment strategies to individual registers, and data items collected. These differences need to be considered when applying strategies for combined analysis and in particular, the lack of common data across Europe on co-morbidities and smoking, two potentially important confounders in both treatment decisions and risk of adverse outcomes. Moving forward it is hoped that more registries will be able to participate.
Disclosure of Interest None Declared