Recent research has focused on the increased risk of atherosclerosis in connective diseases (CTD) like lupus and rheumatoid arthritis (RA). Cells and cytokines implicated in RA pathogenesis are also involved in the development and progression of atherosclerosis, which is recognized as an inflammatory condition.1 Inflammation mediates its effects on atherosclerosis both through modulation of traditional risk factors and by directly affecting the vessel wall.

To examine whether particular subgroups of patients with CTD are at increased risk of developing atherosclerotic cardiovascular disease (ASCVD) ,  Francis Alenghat, MD, PhD, at the University of Chicago studied de-identified medical records from more than 287 000 African American and white patients treated at the University’s medical center. CTD— including RA, systemic lupus erythematosus, systemic sclerosis, Sjögren syndrome, dermatomyositis, polymyositis, and unspecified diffuse or mixed connective tissue disease—was present in 8747 patients. Among the different types of CTD, RA was the most common.

ASCVD was defined as myocardial infarction, ischemic heart disease, angina, coronary artery disease, or atherosclerosis of any artery. Of the 287 467 patients in the analytical sample, 26 750 patients were found to have ASCVD. Of these patients, 15 899 were African American (prevalence 10.0%) and 10,851 were white (prevalence 8.4%).  

When Dr Alenghat assessed patients with a diagnosis of any CTD, he found that 29.7% of African Americans with CTD also had ASCVD, which is 3.1-fold higher than the prevalence in African Americans without CTD.  The association was less strong in white patients, with 14.7% of white patients having ASCVD, representing a 1.8-fold higher prevalence as compared to white patients without CTD.

In all forms of CTD, the prevalence of ASCVD was higher in African American patients than in white patients. Multivariate analysis with logistic regression models adjusted for age, sex, and race corroborated a positive interaction coefficient between African American race and CTD, and a negative interaction coefficient between older age and CTD, confirming the association between CTD and ASCVD is stronger in African Americans and in the young.

Summary and Clinical Applicability

In this study, CTD was associated with higher prevalence of ASCVD, and this association is accentuated in African Americans and young adults.  The limitations of the study include its retrospective design and its reliance on diagnostic codes to identify complex disease. It also utilized simplified classifications of race. Thus, correlation, and not necessarily causality, can be drawn between CTD and ASCVD. This correlation can nonetheless inform how physicians evaluate African American or young patients presenting with CTD. 

“The findings show that CTD is associated with higher prevalence of atherosclerotic cardiovascular disease, an association that is accentuated in African-Americans and in young adults,” Alenghat said. “These insights could be used to improve how we evaluate many patients with a wide range of connective tissue diseases.”

“If we were to view the current findings on the backdrop of contemporary cardiovascular risk calculators and statin guidelines, many patients with connective tissue disease could reasonably consider moderate-intensity statin therapy at age 35,” he said.

Reference

1. Dave AJ, Fiorentino D, Lingala B, et al. Atherosclerotic cardiovascular disease in hospitalized patients with systemic sclerosis: higher mortality than patients with lupus and rheumatoid arthritis. Arthritis Care Res (Hoboken). 2014 Feb;66(2):323-327. doi: 10.1002/acr.22152.

2.  Alenghat FJ. The prevalence of atherosclerosis in those with inflammatory connective tissue disease by race, age, and traditional risk factors. Sci Rep. 2016; Feb 4;6:20303. doi: 10.1038/srep20303.