Considerations in the treatment of insulin resistance and related disorders with a new sympatholytic agent

BACKGROUND: Prospective studies have documented the importance of blood glucose control in diabetic patients for risks for cardiovascular diseases. At age 70 years, more than 30% of people are hypertensive and among these about one-third have diabetes or impaired glucose tolerance. It is urgent to treat hypertension in these patients with drugs that do not further impair glucose control. DRUG STUDIES: Prospective, randomized studies with antihypertensive drugs have demonstrated differences between different classes of drugs regarding effects on insulin sensitivity. Thus, treatment with beta-blockers or diuretics is associated with impaired insulin sensitivity, whereas most modern calcium channel blockers and angiotensin converting enzyme inhibitors are neutral. The most pronounced improvements have been obtained with alpha1-blockers. A new class of drugs, imidazoline I1-imidazoline receptor agonists, may be of interest in this context. Moxonidine, a drug in this class, inhibits sympathetic outflow and causes vasodilation. This effect together with other characteristics may lead to improved insulin resistance and glucose control. CONCLUSIONS: In populations at high risk for diabetes, it may be justified to select drugs that improve insulin sensitivity when treating insulin-resistant individuals for hypertension.