SLE (systemic lupus erythematosus) is characterized by accelerated atherosclerosis. The risk of suffering an acute myocardial infarction among premenopausal women with SLE is 50 times higher than control women of the same age. Insulin resistance and hyperinsulinemia are frequent in SLE. Lipid metabolism in SLE, as in other insulin resistant states, is characterized by high triglycerides, low HDL-cholesterol, normal LDL cholesterol (or slightly increased) and an increase in LDL's susceptibility to oxidation.
All these alterations can produce endothelial dysfunction which is present in SLE patients. Pioglitazone is a PPAR (peroxisome proliferator activated receptor) gamma agonist that can potentially improve insulin resistance, with a positive effect on the lipid profile (lowering of triglycerides, and a discrete increase in HDL-C) and improve endothelial function.
Patients will be randomized to receive either placebo or pioglitazone 30 mg/day during a period of 12 weeks. Endothelial function will be assessed by Positron Emission Tomography (PET).