Risk for acute coronary syndrome reduced among RA patients treated with TNFi

SAN DIEGO — Patients with rheumatoid arthritis treated with tumor necrosis factor inhibitors experienced a slightly reduced risk for acute coronary syndrome, according to study results presented at the American College of Rheumatology annual meeting.

“We can see in this nationwide population-based study a lower risk of acute coronary syndrome [ACS] in patients exposed to tumor necrosis factor inhibitor compared with biologics-naive patients, although we still see that both rheumatoid arthritis cohorts … have an increased risk of ACS compared with the general population,” Lotta Ljung, MD, PhD, senior consultant, rheumatology, Umeå University Hospital, Sweden, told Healio.com.

Ljung and colleagues used a Swedish Biologics Register to identify 7,704 patients (mean age 57.1 years; 75.9% women) with RA and no previous ischemic heart disease who began TNF inhibitor (TNFi) therapy in 2001 to 2010. A cohort of patients with two or more outpatient diagnoses of RA was used to select 23,112 matched biologics-naive patients, and 38,520 matched general population participants were randomly selected.

Patient groups were defined as: actively on TNFi, until date of termination of TNFi therapy plus 90 days; short term exposure, limited follow-up on TNFi to 2 years; and ever exposed to TNFi.

Primary discharge diagnoses of myocardial infarction, unstable angina, and myocardial infarction as the underlying cause of death were the outcome incident ACS.

When TNFi-exposed RA patients were compared with biologics-naive RA patients, the adjusted hazard ratios were 0.78 (95% CI, 0.61-1.01) for short-term exposure; 0.73 (95% CI, 0.60-0.89) for actively on TNFi, and 0.82 (95% CI, 0.70-0.95) for ever-exposed patients.

In comparing bio-naive RA patients with the general population, short-term exposure indicated an adjusted HR of 2.27 (95% CI, 1.88-2.73), while those actively on TNFi had an aHR of 2.10 (95% CI, 1.82-2.43) and ever-exposed patients had an aHR=2.03 (95% CI, 1.80-2.29) for ACS risk. The TNFi cohort had corresponding aHRs of 1.65 (95% CI, 1.23-2.22), 1.50 (95% CI, 1.21-1.85) and 1.61 (95% CI, 1.36-1.92) compared with the general population arm.

“Compared with the general population, the risk of ACS in RA was increased, although less pronounced among the TNFi-exposed patients,” the researchers concluded. “The decrease in risk could be attributable to the TNFi per se, or correspond to a higher degree of inflammatory control in the treatment group.”

Disclosure: See the abstract for a full list of relevant financial disclosures.

For more information:

Ljung L. #804: Tumor Necrosis Factor Inhibitors and the Risk of Acute Coronary Syndrome in Rheumatoid Arthritis — A National Cohort Study. Presented at: the 2013 American College of Rheumatology Annual Meeting; Oct. 26-30, San Diego.