Insulin resistance in African Americans

Hypertension and diabetes mellitus are the leading contributors to end-stage renal disease. African Americans suffer higher rates of renal failure as well as other vascular morbidities associated with hypertension and diabetes. Insulin resistance is strongly associated with hypertension. Insulin resistance is a component of diabetes and also precedes the clinical expression of type 2 diabetes. The relationship of blood pressure with insulin resistance, or impaired insulin action, occurs in African Americans and can be detected at young ages prior to the clinical expression of hypertension or diabetes. Through its relationship with hypertension, diabetes, and hyperlipidemia, insulin resistance is associated with endothelial dysfunction. The interface of insulin resistance with endothelial dysfunction may begin to explain the role of insulin resistance in vascular and renal pathology. The injury process, subsequent to both hypertension and diabetes, appears to be mediated by alterations tissue regulatory factors, and include vasoactive peptides such as angiotensin II, endothelin, and growth factors. Understanding the determinants that up-regulate the aberrant pathways and the early phases of these processes will be necessary to formulate strategies to effectively achieve renal protection and reduce the rates of renal failure in African Americans.