Treatment of hypertension in patients with diabetes: lessons from recent trials

Hypertension plays a critical role in causing a high rate of cardiovascular events in patients with diabetes mellitus. Large trials show that lowering blood pressure in the patient with diabetes who has hypertension has profoundly favorable effects. This review discusses recent trials to answer the question of how low patients' blood pressure should go and which agents should be used to achieve this goal. The National Institutes of Health's guidelines, published in the Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, call for a blood pressure goal of <130/85 mmHg in patients with diabetes. Based on data from the recent trials, an even lower blood pressure of <130/80 mmHg in patients with diabetes and hypertension appears to be appropriate. Observational studies show that the lowest cardiovascular event rate is observed in patients with diabetes whose systolic blood pressure is <120 mmHg. Thus, goal blood pressure in patients with diabetes who have hypertension may need to be revised lower, to <120/80 mmHg. In patients with overt proteinuria of 1 g/d or more, mean arterial pressure of <92 mmHg is recommended. Available evidence justifies the use of angiotensin-converting enzyme (ACE) inhibitors as first-line agents and angiotensin receptor blockers in those patients who are intolerant to ACE inhibitors. Because the blood pressure goal is lower in patients with diabetes who are hypertensive, these patients require the use of multiple agents. Diuretics or long-acting calcium channel blockers are logical second choices because of their synergistic blood pressure reduction effect observed with ACE inhibitors. Alpha-blockers should be used with caution, however. In patients with renal disease, loop diuretics may be required to reduce sodium and volume overload and to improve blood pressure control.