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Objective: To quantify the independent role of each of low-density lipoprotein cholesterol (LDL-C), total cholesterol:high-density lipoprotein cholesterol ratio (TC:HDL-C), triglyceride (TG) level, and HDL-C as a marker of coronary risk in systemic lupus erythematosus (SLE)., Methods: Patients with lipid measurements taken before a coronary event (or last clinic visit) were included. Mean and time-adjusted mean (TAM) levels were calculated for each lipid variable in each patient. Time-dependent proportional hazards regression models were used to quantify the risk of coronary event [myocardial infarction (MI) or angina], after adjustment for age., Results: Among 384 patients, over a mean (SD) followup of 3.81 (2.58) years, there were 21 "first" coronary events (6 MI, 15 angina). Mean and TAM LDL-C (HR 1.83, 95% CI 1.19-2.81, p = 0.006), TC:HDL ratio (HR 1.43, 95% CI 1.02-2.00, p = 0.04), and TG (HR 2.11, 95% CI 1.32-3.39, p = 0.0019) were predictive of coronary event at subsequent visits. In contingency table analysis, TAM LDL-C cutpoint of 2.0 mmol/l had a sensitivity and negative predictive value for coronary event of 85.7% (95% CI 63.7-97.0) and 93.9% (95% CI 83.1-98.7), respectively. However, at this cutpoint the specificity was only 12.7% (95% CI 9.4-16.5)., Conclusion: This study links LDL-C, TC:HDL-C ratio, and TG to coronary risk in patients with SLE and quantifies the magnitude of this risk. SLE-specific risk assessment levels for lipids may be selected to optimize positive or negative predictive values.

Introduction: Previous studies have shown that traditional risk factors such as hypercholesterolemia and hypertension account for only a small proportion of the dramatically increased risk of atherosclerotic coronary artery disease (CAD) in systemic lupus erythematosus (SLE). However, in these studies, exposure to risk factors was measured only at baseline. In this study, our objective was to compare measures of cumulative exposure with remote and recent values for each of total cholesterol (TC), systolic (SBP), and diastolic (DBP) blood pressure in terms of ability to quantify risk of atherosclerotic CAD in patients with SLE., Methods: Patients in the Toronto lupus cohort had TC and BP measured at each clinic visit and were followed up prospectively for the occurrence of CAD. For each patient, arithmetic mean, time-adjusted mean (AM) and area-under-the-curve (AUC) were calculated for serial TC, SBP, and DBP measurements. Proportional hazards regression models were used to compare these summary measures with recent and first-available ("remote") measurements in terms of ability to quantify risk of CAD events, defined as myocardial infarction, angina, or sudden cardiac death., Results: The 991 patients had a mean ± SD of 19 ± 19 TC measurements per patient. Over a follow-up of 6.7 ± 6.4 years, 86 CAD events occurred; although remote TC was not significantly predictive of CAD, mean and AM TC were more strongly predictive (hazard ratio (HR) 2.07; P = 0.003) than recent TC (HR 1.86, P = 0.001). AUC TC was not predictive of CAD. A similar pattern was seen for DBP and SBP. Older age, male sex, higher baseline and recent disease activity score, and corticosteroid use also increased CAD risk, whereas antimalarials were protective., Conclusions: In contrast to the population-based Framingham model, first-available TC and BP are not predictive of CAD among patients with SLE, in whom measures reflecting cumulative exposure over time are better able to quantify CAD risk. This is an important consideration in future studies of dynamic risk factors for CAD in a chronic relapsing-remitting disease such as SLE. Our findings also underpin the importance of adequate control of SLE disease activity while minimizing corticosteroid use, and highlight the cardioprotective effect of antimalarials.

Our objective was to compare brachial artery endothelium dependent and independent vasodilation in lupus patients and healthy females, by means of high-resolution noninvasive brachial artery ultrasound. Endothelially mediated vasodilation was estimated noninvasively by examination of brachial artery responses to postischemic reactive hyperemia and endothelial independent vasodilation from response to sublingual glycerlynitrate (GTN) using high-resolution external vascular ultrasound. Five patients with known coronary artery disease (CAD), five with subclinical CAD, five with no CAD and five control subjects were assessed. Endothelium dependent vasodilation was significantly blunted in lupus patients with CAD as compared with healthy female controls (0.11 versus 11.1%, P = 0.018). Corresponding values for lupus patients with subclinical CAD and no CAD were 11 and 9.6%, respectively. For each subject, endothelium dependent vasodilation (EDV) was related to endothelium independent vasodilation (EIV) to adjust for varying vascular smooth muscle responses to GTN in individual subjects. This ratio was markedly depressed in lupus patients with CAD as compared with control subjects (0.12 versus 1.15). The corresponding EDV/EIV ratios for patients with subclinical CAD and no CAD were similar at 0.69 and 0.65, respectively. The conclusion was that flow mediated vasodilation in lupus patients with coronary artery disease is markedly depressed as compared to healthy subjects. [ABSTRACT FROM AUTHOR]