Increased CV Events in RA Not Likely Due to Differences in Risk Factor Management

TOPIC SERIES: CVD PREVENTION IN RHEUMATIC DISEASE

Researchers have found no difference in the frequency of testing and treatment of cardiovascular (CV) risk factors in patients with rheumatoid arthritis (RA) as compared to patients without RA, suggesting that higher CV risk in RA patients is not likely to be driven by differences in management of traditional CV risk factors. The findings were reported in Rheumatology.

According to Daniel H. Solomon, MD, MPH, from the Division of Rheumatology at Brigham and Women’s Hospital in Boston, Massachusetts and colleagues, “the current literature does not fully address how the traditional CV risk factors of hypertension, lipids, weight, and hemoglobin A1c (HbA1c) are managed in RA patients in comparison to the general population. Thus, the literature fails to inform whether the increased risk of CV events observed in RA patients could partly be due to worse CV risk management.”

In order to examine CV risk management in patients with and without RA, the researchers conducted a retrospective cohort study using data from the UK Clinical Practice Research Datalink, which contains information on resources managed by general practitioners. They identified 24 859 patients with RA and matched them to 87 304 patients without RA. 

The groups had similar baseline characteristics, including baseline blood pressure, lipoprotein, and Hb-A1c levels, although C-reactive protein and erythrocyte sedimentation rate were higher RA patients at diagnosis and decreased over time.

The number of patients with RA prescribed antihypertensives increased from 38.2% at diagnosis to 45.7% at 5 years; the number of patients prescribed lipid-lowering treatments increased from 14.0% to 20.6%, and for antidiabetics, increased from 5.1% to 6.4%. Similar treatment percentages were seen in patients without RA, although the percentage of antihypertensives prescribed was slightly lower. RA patients also had a modest (2%) but significantly lower attainment of lipid and diabetes goals at 1 year.

“Our general finding that there is no substantial difference in the evaluation, treatment, and attainment of CV risk factor goals indicates that the higher incidence of CV events among RA patients observed in our data (CV  event incidence rate in our data set of 4.29, 95% CI 4.15,4.44 in RA patients vs 3.11, 95% CI 3.04, 3.17 in non-RA patients per 100 patient-years; 8.97% of RA patients and 6.97% of non-RA primary prevention patients had a CV event over a 5 year follow-up) may not be driven by poor management of traditional CV risk factors alone,” the authors wrote.

“This finding indirectly supports the literature indicating that there might be other factors contributing to increased CV events in RA patients. Although traditional risk factors are known to play an important role in the general population, their relative contributions to CV risk in RA [are] less clear.”

The researchers also noted that evidence supporting the increased prevalence of hypertension in patients with RA is mixed, because reports are contradictory and depend on the definition of hypertension used in the study. “However, results from a recent study indicate a significantly increased prevalence of hypertension in RA patients vs controls and would support our findings,” they added.

Summary and Clinical Applicability

No differences were found between CV risk factor management and testing in RA and non-RA patients in the UK.

The researchers also noted that further studies are needed to confirm their observation of modestly lower lipid goal attainment in RA patients, especially given that new therapies for RA have been associated with increasing lipid levels.

Limitations and Disclosures

This study was retrospectively conducted, introducing sources of bias due to confounding factors. Only data from general practice was available, thus identification of RA patients could be affected, leading to potential false positives. Finally, NCEP guidelines were used to categorize the RA into different CV risk categories as these were the guidelines available in 2011; results could be different if new ACC/AHA were used to match patients.

Despite these limitations, the study was based on a large sample size and a good follow-up period, and its results are generalizable to the UK population and are representative of its clinical practice.

This study was supported by Bristol-Myers Squibb.

Read More: CVD Risk Mitigation in Rheumatic Disease

Reference

Alemao E, Cawston H, Bourhis F, et al. Cardiovascular risk factor management in patients with RA compared to matched non-RA patients. Rheumatology. 2016;55:809-816. doi:10.1093/rheumatology/kev427.