SLE Associated With Elevated Risk for Atherosclerosis

Danish patients with systemic lupus erythematosus (SLE) but without prior cardiovascular disease (CVD) exhibited high rates of atherosclerosis, associated with a variety of cardiovascular risk factors, according to research published in the Journal of Rheumatology.

Susan Due Kay, MD, of the Department of Rheumatology at Odense University Hospital in Denmark, and colleagues conducted a cross-sectional study of a population-based SLE cohort. Adult patients without a prior history of CVD (n = 103) took part in a structured study program that included an extended interview, clinical examination, blood sampling, cardiac computed tomography (CT), ultrasound of the carotid arteries, and ankle systolic blood pressure measurements.   Prior history of CVD was defined as having a history of myocardial infarction, arterial revascularization, stroke, or symptomatic lower extremity peripheral artery disease.

Researchers used coronary artery calcification (CAC) and plaque formation as surrogate markers of coronary and carotid atherosclerosis.  Abnormal ankle-brachial index (ABI) was used as a surrogate marker of lower-extremity atherosclerosis.

Upon analysis, the researchers found that 44 patients (42.7%) exhibited signs of CAC; 19 patients (18.4%) exhibited mild CAC, 10 patients (9.7%) exhibited moderate CAC, and 15 patients (14.6%) exhibited high CAC. Atherosclerosis in any vascular territory was found in 42 patients (41%) overall.

The presence of atherosclerosis was significantly associated with male sex, older age, increased waist circumference, hypercholesterolemia, and positive smoking history after multivariate analysis was applied.

“Several previous studies of atherosclerosis in patients with SLE have been performed, but only a few are population-based and of European origin, and more than one imaging modality is rarely used,” wrote Dr Kay.

“Our results indicate that [diagnostic] screening for atherosclerosis in 1 vascular territory is insufficient,” Dr Kay added. Eleven of 27 patients with carotid atherosclerosis and 8 out of 12 patients with lower-extremity atherosclerosis would have gone undiagnosed if only cardiac CT were employed; similarly, carotid ultrasounds alone would have missed 9 out of 25 and 7 out of 12 patients with coronary atherosclerosis and lower-extremity atherosclerosis, respectively.

“Traditional CV risk factors are important, but not alone responsible for the accelerated development of atherosclerosis in SLE,” the researchers concluded.

Summary and Clinical Applicability

This cross-sectional study demonstrated that signs of atherosclerosis were detected in more than 1 vascular territory in a population of Danish patients with SLE who did not have a prior history of CVD. However, the particular distribution of atherosclerosis in the 3 vascular territories that were examined differed.  Based on these results, it was concluded that screening for atherosclerosis in a single vascular territory may not be all encompassing, and on its own may not be adequate to diagnose atherosclerosis of CVD in SLE.   Absence of disease in one vascular territory did not necessarily correlate with absence of disease in another territory.

Reference

Kay SD, Poulsen MK, Diederichsen ACP, Voss A. Coronary, carotid, and lower-extremity atherosclerosis and their interrelationship in Danish patients with systemic lupus erythematosus. J Rheumatol. 2016;43(2):315-322. doi: 10.3899/jrheum.150488