Treatment with metoprolol succinate, aselective beta adrenergic blocker, lowersblood pressure without altering insulinsensitivity in diabetic patients

Abstract

Insulin resistance is a risk factor for cardiovasculardisease. Therapies to lower blood pressureshould not decrease insulin sensitivity, especiallyamong high-risk patients such as diabetics. Thisstudy examined the effect of the b1-selectiveadrenergic receptor-blocking agent extendedreleasemetoprolol succinate (ER metoprolol)on insulin sensitivity in type 2 diabetic patientswith suboptimal blood pressure control. Diabeticpatients with average blood pressure levels>130/85 mm Hg despite antihypertensive therapyhad insulin sensitivity quantified by insulin clamp.ER metoprolol was then added to their ongoingtherapy. Following 12 weeks of ER metoprololplus other therapy, the insulin clamp study wasrepeated. There were no significant changes inmeasures of insulin sensitivity, plasma lipids, or hemoglobin A1c with use of ER metoprolol.When b-blocker therapy is considered, it appearsthat this agent can be used to treat hypertensionwithout adverse effects on insulin sensitivityin patients with type 2 diabetes, at least overthe period of time treated. © 2008 Le Jacq.