MADRID – Measuring levels of troponin, a well-known cardiac biomarker, could help identify patients with systemic lupus erythematosus (SLE) at particularly high risk for cardiovascular (CV) events, according to the results of a cross-sectional study presented at the European Congress of Rheumatology.
Karim Sacré, MD, presented the findings of the study that looked for possible biomarkers of atherosclerosis in patients with SLE and provide preliminary evidence that high-sensitivity troponin T (HS-cTnT) was predictive regardless of whether or not patients already had visible atherosclerotic plaques on vascular ultrasound.
“Patients with SLE have been known to be at risk for cardiovascular disease for at least a decade,” Dr. Sacré of Bichat Hospital, University of Paris-Diderot, France, said in an interview at the meeting. Today, SLE is considered an independent risk factor for CV events, much like diabetes, he added.
However, determining which patients with lupus will and which will not develop cardiac problems is still tricky in routine practice. This is because the traditional ways of assessing CV events do not fully account for the increased risk seen in lupus patients. Indeed, the Framingham risk score, which is based on several risk factors such as tobacco use, hypertension, and dyslipidemia, has been shown to underestimate the cardiovascular risk of lupus patients, he observed.
“So, we need something that will help clinicians to better define the real risk of cardiovascular disease in such populations,” he said at an earlier press conference.
Thus, the objective of the study he presented was to try to find a biomarker in the blood that might aid clinicians in identifying which patients who had SLE and no obvious cardiac symptoms might be at risk for future CV events.
The study involved 63 patients with SLE who were consecutively recruited and 18 individuals without SLE who were used as controls. None had any symptoms of cardiovascular disease at recruitment, and all were assessed prospectively by vascular ultrasound for the presence of atherosclerotic plaques in the carotid artery.
The concentration of HS-cTnT was measured in the serum by using an electrochemiluminescence method, which could detect a concentration level greater than 3 ng/L .
At recruitment, the Framingham risk score was low (2.1) in both patients and controls, none of whom showed any signs of already having cardiovascular disease. The results of the carotid ultrasound, however, showed a different story for the SLE patients, with 23 (36.5%) identified as having carotid plaques, compared with just 2 (11.1%) of the control group.
Serum HS-cTNT could be detected in more SLE patients than controls (58.7% vs. 33.3%; P = .057), and the SLE patients who had detectable levels were nine times more likely than controls to have a carotid plaque, Dr. Sacré reported, although the 95% confidence interval was wide (1.55 to 90.07; P = .033).
Interestingly, a higher percentage of SLE patients with carotid plaques than those without had detectable HS-cTNT (87% vs. 42.5%; P less than .001). Conversely, more patients with detectable HS-cTnT than without had a carotid plaque (54.5% vs. 11.5%; P less than .001).
In multivariate analyses, only SLE status and age were significantly associated with having carotid plaques, and body mass index and HS-cTnT (P = .033) were statistically associated with the presence of carotid plaques in SLE patients.
The research is, of course, preliminary, Dr. Sacré emphasized, and further investigation is needed. The study looked at subclinical disease rather than actual CV events, and that is something to look at next in a larger cohort of patients with a longer follow-up period, he said.
Dr. Sacré disclosed that he had received support for travel to the EULAR Congress from Roche Diagnostics France.
*This story was updated 6/20/2017.