Hypertension as a risk factor syndrome: therapeutic implications.

Reduction of blood pressure as the only therapeutic goal of antihypertensive treatment may no longer be appropriate. High blood pressure is associated with an increased risk of cardiovascular events, but clinical trials of antihypertensive therapy have shown an inconsistent reduction in major cardiovascular endpoints. Importantly, the incidence of coronary artery disease has been reduced to only a small extent, suggesting that factors beyond high blood pressure are important in the genesis of atherosclerotic disease in hypertensive patients. It is evident, for example, that patients with hypertension have an exaggerated vulnerability to the consequences of lipid abnormalities. Moreover, it has recently been established that hypertension is characterized by insulin resistance and altered glucose tolerance. As a result, high plasma concentrations of insulin produce proliferative effects on vascular smooth muscle and connective tissue, and they may adversely affect the lipid profile. The left ventricle is also involved in hypertension, independent of blood pressure. There is growing evidence that there are increases in the muscle mass of the left ventricle and changes in its diastolic filling characteristics at very early stages of hypertension. The arterial circulation is similarly involved, for alterations in structure or function (reflected by diminished arterial compliance) can be demonstrated prior to the appearance of clinical hypertension. New therapeutic strategies should be aimed at the full spectrum of hypertension-related changes. Because the renin-angiotensin system can contribute to the structural and functional cardiovascular characteristics of this condition, such agents as angiotensin-converting enzyme inhibitors may be especially effective in preventing or reversing these abnormalities and are emerging as a treatment of choice for hypertension.