Background: The advent of biologics in the late 1990s radically changed the profile of inflammatory diseases, in particular rheumatoid arthritis (RA). The survival of these innovative therapies is an indicator, in clinical practice, of their long-term efficiency in patients with RA.

Objectives: To study the influence of comorbidities on biologics drugs retention rates.

Methods: We conducted a cross-sectional, observational study. Data were identified from the files of the National Health Insurance Fund of Tunis. It included patients with RA on biologics. Epidemiological characteristics such as age, sex, and comorbidities, were collected. Comorbidities were assessed by the Charlson Comorbidity Index (CCI). The therapeutic maintenance rate at 12, 24, 36, and 48 months as well as the biologics survival were analyzed using Kaplan-Meier survival curves and compared using the Log-Rank test.

Results: Three hundred and seventy-four files were selected. The average age of our cohort was 55±12.54 years [20-90]. A female predominance was noted with a sex ratio M/F=0.147. The average duration of RA was 11.7±6.76 years [2-41].First biogics prescription was: etanercept 54%, adalimumab 14%, certolizumab pegol 13%, infliximab 6%, tocilizumab 6% and rituximab 7%. First-line survival rates at 12, 24, 36, and 48 months were 85.8; 69.9; 60.6, and 55.9% respectively. Biologics drug survival was, on average, 41.7 months [39.47-43.91]. Comorbidities were assessed by the CCI in 373 patients (99.7%). Ninety patients had an ICC of 0 and 103 patients had an ICC of 1. Only one patient had an ICC of 8. The median value of this score was equal to 1, the mean was 1.64 ± 1.48. Osteoporosis was the most observed comorbidity with 78 patients (20.9%). The study of drug survival according to the ICC did not show any significant difference between the different curves (p=0.809). The Hazard Ratio was 0.999. Similarly, we did not find a discriminating threshold for the Charlson score, allowing it to be decisive for the survival of biologic drugs.

Conclusion: This study did not identify the influence of comorbidities on the biologics survival during RA. Comorbidities can have an impact not only on our therapeutic choice but also on the efficacy and maintenance of biomedicines as well as the quality of life of patients and consequently the prognosis of RA (1). The few studies that have looked at this subject have produced variable results.

REFERENCES:

[1]Estíbaliz Loza, Cristina Lajas, Jose Luis Andreu, Alejandro Balsa, et al. Consensus statement on a framework for the management of comorbidity and extra-articular manifestations in rheumatoid arthritis. Rheumatol Int 2015 Mar;35(3):445-58.

Disclosure of Interests: None declared