What is the role of obesity in hypertension and target organ injury in African Americans?

Hypertension is the most common reversible risk factor for cardiovascular disease. It is especially common in African Americans. One of the factors that may contribute to the high rates of hypertension and target organ injury in African Americans is obesity. Hypertension and obesity are common among African Americans. Obesity is particularly common in African American women. About 75% of African American women are obese. Regulation of both body weight and blood pressure are complex, involving an interaction of genetic and environmental factors. Most research thus far has focused on blood pressure control systems studied in other forms of hypertension, including the sympathetic nervous system, the renin angiotensin system, and metabolic factors-primarily insulin resistance. Proposed mechanisms that are unique to obesity-associated hypertension include: 1) intrarenal physical forces associated with obesity-induced changes in the renal medulla; 2) genetic/metabolic factors; and 3) metabolic effects of abdominal visceral fat. The Jackson Heart Study provides a unique opportunity to address unresolved questions in the relationship of body weight, blood pressure, and cardiovascular disease.