Treatment of the elderly hypertensive patient.

Changes due to aging of the cardiovascular system play an important role in the development of hypertension and its complications in the elderly. As shown in recent experimental studies in rats, the arterial changes that normally take place resemble those resulting from hypertension. They may be preventable by maintenance of low blood pressures and may be secondary to prolonged hemodynamic effects on the artery wall. The major hemodynamic consequences of aging in man include an increase in total peripheral vascular resistance, which occurs as a result of both arterial and arteriolar disease. Other features with potentially important therapeutic implications in the elderly include an increased tendency for left ventricular dysfunction and cardiac arrhythmias, decreased baroreceptor sensitivity, and atherosclerosis-induced reduction of blood flow to vital organs. Older patients also tend to have a reduced fluid volume and an abnormal distribution and metabolism of drugs. These factors lead to greater sensitivity to potential side effects and, thus, greater difficulty in managing their hypertension. Diuretics, beta blockers, and calcium channel blockers appear to be the most useful initial antihypertensive drugs in the elderly. The cardioprotective effects of beta blockers and the desirable hemodynamic action of calcium antagonists provide compelling justification for their use in many patients. Centrally acting sympatholytic drugs such as methyldopa, clonidine, and guanabenz are useful as second-step agents, usually in combination with a diuretic. In the presence of moderate to severe diastolic hypertension, hydralazine, captopril, and minoxidil may have value, but such potent agents should generally be avoided with isolated systolic hypertension. In elderly hypertensive patients with other complicating diseases, sufficient alternative treatment options are now available to allow tailoring of therapy to the special needs of each patient, thereby minimizing adverse reactions to therapy. However, relatively low doses of medications and conservative therapeutic objectives are usually necessary, particularly in patients with isolated systolic hypertension in whom the benefits of treatment are still to be determined.