Patients with
systemic lupus erythematosus (SLE) have accelerated
atherosclerosis, but the underlying mechanisms are unclear. The size and number of
lipoprotein particles may be better predictors of
atherosclerosis than conventional
cholesterol measurements. We measured
lipoprotein subclasses by
nuclear magnetic resonance spectroscopy (
NMR),
coronary artery calcification by
electron beam
computed tomography, and
insulin resistance by homeostasis model assessment in 105 patients with SLE and 77 control subjects.
VLDL particles were larger (50.0 +/- 8.5 versus 47.7 +/- 8.5 nm, P = 0.01) and concentrations of large
high-density lipoprotein (HDL) particles lower (10.1 +/- 5.3 versus 11.3 +/- 5.1 nmol/L, P = 0.03) in patients with SLE than controls. In patients with SLE, small
LDL concentration was associated with
body mass index (rho = 0.27),
insulin resistance (rho = 0.34),
C-reactive protein (CRP; rho = 0.30), and
erythrocyte sedimentation rate (ESR; rho = 0.20); all P < 0.05. Large HDL concentration was inversely associated with
insulin resistance (rho = -0.29), disease activity (rho = -0.23), and ESR (rho = -0.39); all P < 0.05.
VLDL concentrations
correlated with CRP (rho = 0.22), ESR (rho = 0.24), disease damage (rho = 0.20), and
corticosteroid exposure (rho = 0.29); all P < 0.05. Neither the concentration of
lipoprotein subclasses nor particle size was associated with
coronary artery atherosclerosis. There were only minor differences in the
NMR lipid profiles of patients with SLE and controls.
Lipoprotein subclasses were associated with
metabolic variables,
inflammatory markers, and
corticosteroid use but not with
coronary artery atherosclerosis in SLE.
