Coronary Calcium in Systemic Lupus Erythematosus Is Associated with Traditional Cardiovascular Risk Factors, But Not with Disease Activity

ADNAN N. KIANI, LAURENCE MAGDER, and MICHELLE PETRI

ABSTRACT.

Objective. Cardiovascular disease is a major cause of morbidity and mortality in systemic lupus erythematosus (SLE). The frequency of both subclinical and clinically evident atherosclerosis is greatly increased over healthy controls. We assessed cardiovascular risk factors present in patients with SLE at the baseline visit in a statin intervention trial and their correlation with coronary calcium.

Methods. Coronary calcium was measured by helical computed tomography (continuous volumetric data acquisition in a single breath-hold) in 200 patients with SLE enrolled in the Lupus Atherosclerosis Prevention Study.

Results. Patients had a mean age of 44.3 ± 11.4 years and were 92% women, 61% Caucasian, 34% African American, 2% Asian, and 2% Hispanic. Coronary calcium was found in 43%. In univariate analysis, coronary calcification was associated with age (p = 0.0001), hypertension (p = 0.0008), body mass index (BMI; p = 0.03), erythrocyte sedimentation rate (ESR; p = 0.03), anti-dsDNA (p = 0.067), and lipoprotein(a) (p = 0.03). Homocysteine (p = 0.050), high-sensitivity C-reactive protein (hsCRP; p = 0.053), and LDL (p = 0.048) had a stronger association when considered as quantitative predictors. In a multiple logistic regression model, only age (p ≤ 0.0001) and body mass index (p = 0.0014) remained independent predictors. No measure of SLE activity was associated with coronary calcium. We also examined variables independently predictive of a coronary calcium score > 100. Based on a multiple logistic regression model, only age (p = 0.0017) and diabetes mellitus (p = 0.019) remained significant independent predictors of coronary calcium > 100.

Conclusion. Inflammation, measured as ESR or hsCRP, is associated with coronary calcium only in univariate analyses. Age, BMI, and diabetes mellitus are more important associates of coronary calcium in SLE than inflammatory markers and SLE clinical activity. (J Rheumatol First Release May 15 2008)

Key Indexing Terms:

CORONARY CALCIUM
SYSTEMIC LUPUS ERYTHEMATOSUS
CARDIOVASCULAR RISK FACTORS
DISEASE ACTIVITY

---

From the Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore; and the University of Maryland, Baltimore, Maryland, USA.

The Lupus Atherosclerosis Prevention Study is supported by a grant from the Alliance for Lupus Research, Johns Hopkins General Clinical Research Center (M01-RR00052), Bayview General Clinical Research Center (M01-RR02719), and the Hopkins Lupus Cohort (NIH AR 43727).

A.N. Kiani, MD, MPH, Research Fellow; M. Petri, MD, MPH, Professor of Medicine, Division of Rheumatology, Johns Hopkins University School of Medicine; L. Magder, PhD, Associate Professor of Epidemiology and Preventive Medicine, University of Maryland.

Address reprint requests to Dr. M. Petri, Division of Rheumatology, Johns Hopkins University School of Medicine, 1830 East Monument Street, Suite 7500, Baltimore, MD 21205, USA. E-mail: mpetri@jhmi.edu

Accepted for publication February 13, 2008.