Performance of Risk Score Calculators in the Identification of Coronary Artery Calcification in Patients With Systemic Lupus Erythematosus

Objective We aimed to evaluate the performance of cardiovascular (CV) risk prediction tools in identifying patients with systemic lupus erythematosus (SLE) with coronary artery calcification (CAC).

Methods We conducted a post hoc analysis of a prior case-control study of adult female patients with SLE and matched controls. We excluded patients who already met cardiology guidelines for recommended statin use. We risk-stratified patients per Atherosclerotic CV Disease (ASCVD) Risk Score and SLE-specific CV Risk (SLECRISK) score and determined rates of abnormal CAC. We used 2-sample t tests, 2-sample Wilcoxon rank-sum (Mann-Whitney) tests, and chi-square tests to compare various characteristics between subgroups, and used logistic regression to assess adjusted risk for patients with SLE compared to controls.

Results We analyzed 128 patients with SLE and 138 controls. Rates of abnormal CAC in the SLE and control groups were 31.3% (40/128) and 12.3% (17/138), respectively, with similar mean ASCVD Risk Scores (2.2% vs 1.9%). Both the ASCVD Risk Score and SLECRISK score had relatively high specificity (95-100%) for abnormal CAC. The ASCVD score demonstrated poor sensitivity in both control (17.6%) and SLE (15%) groups, with sensitivity doubling to 30.8% among patients with SLE with the use of the SLECRISK score. Among participants with SLE who had low ASCVD risk, those with abnormal CAC were more likely to be older and have lower glomerular filtration rate, longer disease duration, higher insulin resistance, and higher low-density lipoprotein and cholesterol levels.

Conclusion The poor performance of conventional and even modified risk scores suggests a continued need for screening approaches, including CAC, to determine CV disease risk in the SLE patient population.