NEW YORK (Reuters Health)—Patients with rheumatoid arthritis (RA) are at increased risk of serious infections, myocardial infarction (MI) and coronary heart disease (CHD), an analysis of Medicare claims data suggests.
“Higher disease activity as measured by a panel of biomarkers was associated with higher rates of hospitalized infections, MI and CHD events. These findings add to the growing body of evidence that further strengthens the argument to strive for lower disease activity in RA,” the authors write in Annals of the Rheumatic Diseases, online Dec. 21.1
“This study used a commercially available multibiomarker disease activity test (MBDA), which measures disease activity through blood tests, to examine the relationship between disease activity and developing these comorbidities. This test reflects that active disease is bad because it leads to not only joint damage and disability from the disease itself, but it increases the long-term risks of other problems such as heart attacks and infections,” Dr. Eric L. Matteson, a professor of medicine at Mayo Clinic in Rochester, Minn., tells Reuters Health.
“This study emphasizes the importance of disease control to reduce heart attacks and infections,” advises Dr. Matteson, who was not involved in the study.
Dr. Paul Muntner, a professor of epidemiology at the University of Alabama at Birmingham, and colleagues conducted a longitudinal cohort study of older people living in the U.S. who had RA, were insured by Medicare, and had received MBDA testing as part of standard of care from a rheumatologist.
Using Medicare fee-for-service claims data for 2010–2014, the researchers examined hospitalization for pneumonia/sepsis serious infection events (SIEs), MI and CHD. MBDA test scores, provided by Crescendo Biosciences, ranged from 1 to 100 and were linked to the Medicare data.
The researchers included patients who had had at least one valid MBDA score linked to Medicare claims, as well as Medicare with Part D (pharmacy) coverage for one at least one year before the first valid MBDA test date.
Data from 17,433 and 16,796 patients eligible for the SIE and MI/CHD analyses, respectively, were analyzed. The patients’ mean age was 69, 79% were women, 81% were white, and 38% were disabled.
The researchers excluded patients with psoriatic arthritis, systemic lupus erythematosus, inflammatory bowel disease, most malignancies and other related illnesses, as well as those who had begun to take any non-tumor necrosis factor (TNF) biologic or synthetic, targeted disease-modifying anti-rheumatic drugs (DMARDs). The cohort’s most commonly used medications were methotrexate (54%) and oral glucocorticoids (53%).
Patients with lower MBDA scores tended to be younger, have lower comorbidity burden, and use fewer glucocorticoids—but more biologics.
In all, 452 SIE events, 132 MIs, and 181 CHD events occurred during 16,424 person-years of follow-up.
Higher MBDA scores were significantly associated with SIEs (adjusted hazard ratio, 1.32, per 10-unit MBDA score change). Higher RA disease activity, by MBDA score, was linked with higher adjusted HRs for MI (1.52) and CHD (1.54). Analyses excluding C-reactive protein from MBDA were consistent with the overall results.
Dr. Jonathan Graf, a professor of medicine at the University of California, San Francisco and the director of the Rheumatoid Arthritis Clinic at Zuckerberg San Francisco General Hospital and Trauma Center, tells Reuters Health that the authors used clever means to match disease activity and with claims data.
“This is some of the best data available to suggest a link between RA and heart disease,” Dr. Graf, who also was not involved in the study, notes. “I think these results prove the hypotheses that inflammation drives cardiac disease.”
“These results suggest that we should be treating patients as aggressively as we can,” he advises. “Maybe instead of treating a patient by gestalt, we need to measure the total disease activity present and treat that person to a target.”
“RA is not the only chronic inflammatory disease out there. There are many others. When you add them up—even chronic gum inflammation—if this concept proves to be true and is applicable across all these diseases, maybe the time has come to assess the patient’s total inflammatory burden, and if there is a treatable disease, to lower it,” he adds.
The authors did not respond to requests for comment.
Crescendo Bioscience, a Myriad Genetics Company, partially supported the study. Dr. Curtis has financial relationships with Myriad Genetics.
Reference
- Curtis JR, Xie F, Chen L, et al. Biomarker-related risk for myocardial infarction and serious infections in patients with rheumatoid arthritis: a population-based study. Ann Rheum Dis. 2017 Dec 21. pii: annrheumdis-2017-211727. doi: 10.1136/annrheumdis-2017-211727. [Epub ahead of print]
