Update on the management of hypertension: recent clinical trials and the JNC 7.

The following issues are highlighted: Emphasis is placed on the importance of systolic blood pressure elevations in estimating risk and in determining prognosis. A review of placebo-controlled clinical trials indicates that cardiovascular events are statistically significantly reduced with diuretic- or b blocker-based treatment regimens. The question of whether blood pressure lowering alone or specific medications make the difference in outcome is discussed. Based on the results of numerous trials, it is apparent that blood pressure lowering itself is probably of greater importance in reducing cardiovascular events than the specific medication used. Meta-analyses suggest, however, that the use of an agent that blocks the renin-angiotensin aldosterone system is probably more effective in diabetics and in patients with nephropathy than a regimen based on calcium channel blocker therapy. The Antihypertensive and Lipid-Lowering treatment to Prevent Heart Attack Trial (ALLHAT) reported no overall difference in coronary heart disease outcome among patients treated with a diuretic-based compared to a calcium channel blocker- or an angiotensin-converting enzyme inhibitor-based treatment program. However, patients in the diuretic group experienced fewer episodes of heart failure than in the calcium channel blocker group and fewer episodes of heart failure and strokes than those in the angiotensin-converting enzyme inhibitor group. Results were similar in diabetics and nondiabetics. Possible reasons for this outcome are discussed. The Australian National Blood Pressure 2 study, which was unblinded, reported a marginally significantly better outcome only in male patients receiving an angiotensin-converting enzyme inhibitor-based regimen compared to those receiving a diuretic-based program. Finally, the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) is reviewed. Highlights of this report include the new designation of prehypertension, i.e., blood pressures of 120-139 mm Hg/80-89 mm Hg. The JNC 7 suggested that diuretics should be the first-step drug of choice in most patients, but listed numerous specific reasons why other agents should be used in special situations. The report stressed that the majority of patients will require two or more medications to achieve goal blood pressure.