Biologics reduced mortality risk in patients with rheumatoid arthritis

WASHINGTON — Patients with rheumatoid arthritis who were treated with biologics had a significant reduction in mortality, according to study results presented at the American College of Rheumatology Annual Meeting.

Canadian researchers used Ministry of Health data to study a population-based cohort including all patients with rheumatoid arthritis (RA) in British Columbia who received care from January 1996 through March 2006. Follow-up was through March 2010. Medication used since January 1996 was identified, along with physician visits, hospitalizations and tests since January 1990.

RA patients (n=2,156) treated with a biologic agent (anti-tumor necrosis factor [anti-TNF], rituximab, anakinra or abatacept) during follow-up were identified and matched with 2,156 controls who never used a biologic but used at least three disease-modifying antirheumatic drugs (DMARD) and recently had changed one.

The two groups were matched by age and gender (mean age, 56.3 years; 74.7% women) and inclusion year. Controls were given the initiation date that corresponded to a matched patient’s first use of biologics. Using RA severity markers, a propensity score (PS) was calculated, along with comorbidities that increased mortality risk. PS quintiles were added to the final multivariate model. Death risk associated with biologic exposure was measured by Cox proportional hazard model (PHM).

There were 573 deaths (326, controls; 247, biologic users), with biologics exposure associated with reduced death risk (adjusted HR=0.25; 95% CI, 0.18-0.36). Sensitivity analysis not requiring controls to have used three prior DMARD or a recent change in DMARD displayed almost the same result (aHR=0.26; 95% CI, 0.18-0.36). When PS was not used, but PS variables were allowed to enter the PHM and controls were only required prior use of one DMARD, similar results (aHR=0.31; 95% CI, 0.22-0.45) were achieved in a second sensitivity analysis.

“The risk of death with exposure to biologics is a quarter that of the controls that were not exposed,” researcher Diane Lacaille, MD, FRPC, MHSC, associate professor at the University of British Columbia and senior scientist at the Arthritis Research Centre of Canada, told Healio.com.

“Exposure to biologics is associated with reduction in the risk for mortality,” she said. “We think this is primarily due to a reduction in cardiovascular disease. Anti-TNF agents and biologics are very effective in reducing inflammation.”

For more information:

Lacaille D. P1642: Biologics and Mortality Risk in Rheumatoid Arthritis — Results of a Population Based Study. Presented at: American College of Rheumatology 2012 Annual Meeting; Nov. 10-14, Washington.