Atherosclerosis and renal disease involvement in patients with systemic lupus erythematosus: a cross-sectional cohort study

Objective. To investigate the association between LN, renal function and atherosclerosis measured by coronary artery calcium (CAC) and carotid plaque in a cross-sectional study of patients with SLE. Methods. Presence of CAC and carotid plaque was measured in 147 SLE patients with and without LN. The patients were divided into four groups according to LN and renal function [by first quartile of estimated glomerular filtration rate (eGFR): 70 ml/min/1.73 m(2)]. Impaired renal function was defined by an eGFR <70 ml/min/1.73 m(2). We used multivariate logistic regression models to explore the association between LN, renal function, CAC and carotid plaque. Results. Of the 147 SLE patients, 74 had LN. Median age of the study cohort was 46 years, 89% were women and median eGFR was 89 ml/min/1.73 m(2). CAC score >0 was present in 57 (39%) and carotid plaque in 29 (20%) of the SLE patients. The presence of CAC and/or carotid plaque was highest in SLE patients with impaired renal function. Regression analyses showed that compared with SLE patients without LN and eGFR 570 ml/min/1.73 m(2) (reference group), only the combination of LN and impaired renal function was associated with the presence of CAC (odds ratio: 6.82, 95% CI: 1.59, 29; P = 0.01) and carotid plaque (odds ratio: 5.60, 95% CI: 1.19, 26; P = 0.03). Conclusion. Our findings indicate that LN in combination with impaired renal function defined by an eGFR <70 ml/min/1.73 m(2) is strongly associated with the presence of atherosclerosis in SLE.