Arthritis & Rheumatism, Volume 62,
November 2010 Abstract Supplement
Abstracts of the American College of
Rheumatology/Association of Rheumatology Health Professionals
Annual Scientific Meeting
Atlanta, Georgia November 6-11, 2010.
Carotid Plaque Area Correlates Better Than Intima Media Thickness with Cardiovascular Risk Factors and Clinical Ischemic Heart Disease in Lupus Patients.
Eder, Lihi, Urowitz, Murray B., Ibanez, Dominique, Gladman, Dafna D.
Patients with Systemic Lupus Erythematosus (SLE) have a significantly increased risk of accelerated atherosclerosis and cardiovascular disease (CVD). The extent of sub-clinical atherosclerosis can be assessed by an ultrasound (US) measurement of carotid intima-media thickness (c-IMT) and carotid plaque area (c-PA). In the general population, c-PA correlates with ischemic events better than c-IMT. The aim of this study was to investigate whether c-PA can serve as a preferred surrogate measure for sub-clinical atherosclerosis in SLE.
The study patients were recruited from a large single centre prospective cohort of SLE patients. Demographic, clinical and laboratory information was stored in a computerized database. The database was searched for subjects with a history of a documented ischemic heart event, including angina pectoris or myocardial infarction. Consecutive SLE patients without a history of CVD were recruited as controls. High resolution images were acquired with an optimized US system for carotid imaging. Each plaque was scanned in a longitudinal view until maximum area of the plaque was in the plane of view. The plaque area was measured by tracing the perimeter with a cursor. Total plaque area was recorded as the sum of all plaques in the right and left carotid arteries. Mean c-IMT was measured using a computerized software, in the left and right common carotid arteries. Correlation between c-PA and c-IMT were evaluated. Both measures were compared in patients with and without a history of CVD. To facilitate direct comparisons, c-IMT and c-PA were transformed into z scores. Logistic regressions were used to evaluate the Odds Ratio(OR) and 95% Confidence Interval (95% CI) of c-IMT and c-PA in their association with CVD, hypertension, cholesterol, high density lipoprotein (HDL) and low density lipoprotein (LDL).
72 SLE patients participated in the study, of whom 19 had a history of ischemic heart event. Carotid IMT correlated only moderately with c-PA (r=0.46, p<0.001). Both c-IMT and c-PA were significantly higher in the group with ischemic heart event (712.7 ± 106.7 vs. 606.4 ± 96.0 mm, p<0.001 for c-IMT and 0.447 ± 0.577 vs. 0.048 ± 0.100 p=0.008 cm2 for c-PA). After transforming c-IMT and c-PA into z scores, c-PA showed a stronger association with clinical ischemic event (OR 10.8 95% CI 2.546.9, p=0.001) than c-IMT (OR 2.8, 95% CI 1.55.2, p=0.001). Elevated c-PA was significantly associated with high LDL levels (OR 7.6, p=0.04) and with low HDL level (OR 4.78 p=0.02) however, no association was seen with hypertension or total cholesterol level. Carotid IMT did not correlate with any of the traditional cardiovascular risk factors. None of the measures correlated with SLE disease duration.
In SLE patients, c-IMT correlates moderately with c-PA suggesting that they measure different phenotypes of atherosclerosis. Carotid Plaque area correlated better than c-IMT with cardiovascular risk factors and ischemic heart events suggesting that it may serve as a better tool for investigation of atherosclerosis in SLE.
To cite this abstract, please use the following information:
Eder, Lihi, Urowitz, Murray B., Ibanez, Dominique, Gladman, Dafna D.; Carotid Plaque Area Correlates Better Than Intima Media Thickness with Cardiovascular Risk Factors and Clinical Ischemic Heart Disease in Lupus Patients. [abstract]. Arthritis Rheum 2010;62 Suppl 10 :455