INTERPRETATION Drug-class effects on interindividual variation in blood pressure can account for differences in effects of antihypertensive drugs on risk of stroke independently of effects on mean SBP .
INTRODUCTION Unexplained differences between classes of antihypertensive drugs in their effectiveness in preventing stroke might be due to class effects on intraindividual variability in blood pressure .
We did a systematic review to assess any such effects in r and omised controlled trials .
Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT): Practical Implications
The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial ( ALLHAT ) , sponsored by the National Heart , Lung , and Blood Institute ( NHLBI ) , is the largest outcome trial of antihypertensive treatment ever carried out and the only large blood pressure ( BP ) trial to be carried out in a US population in the past decade.1 The rationale for ALLHAT , which was design ed in the early 1990s , was the urgent need to determine which of the several classes of antihypertensive drugs that had been developed and released for clinical use was most effective in preventing coronary heart disease ( CHD ) , defined as fatal CHD and nonfatal myocardial infa rct ion.2 The only r and omized trials that had previously compared representatives of the antihypertensive drug classes , the Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents3 and the Treatment of Mild Hypertension Study (TOMHS),4 showed BP reductions with all classes but were not powered to evaluate CHD outcomes . Further , prior outcome trials had shown that the reduction in CHD event rates with antihypertensive treatment was less than expected based on epidemiologic data .5 Adverse effects of study drugs , particularly diuretics , including hypokalemia , hypomagnesemia , hyperuricemia , hyperlipidemia , insulin resistance , and ventricular ectopic activity , had been adduced to account for the disappointing outcomes of earlier trials by off setting the beneficial effects of BP reduction.6,7 To further complicate the picture , benefits beyond BP reduction had been attributed to some antihypertensive drug classes , ie , improved survival and reduced morbidity in persons with heart failure or left ventricular dysfunction treated with angiotensin-converting enzyme ( ACE ) inhibitors8–10 and improved insulin sensitivity and lipid profiles with α-blocker treatment.11 In contrast , another antihypertensive drug class , the dihydropyridine calcium channel blockers ( CCBs ) , had been associated with unfavorable outcomes in patients with acute myocardial infa rct ion or unstable angina.12 There were no data
INTERPRETATION Drug-class effects on interindividual variation in blood pressure can account for differences in effects of antihypertensive drugs on risk of stroke independently of effects on mean SBP .
INTRODUCTION Unexplained differences between classes of antihypertensive drugs in their effectiveness in preventing stroke might be due to class effects on intraindividual variability in blood pressure .
We did a systematic review to assess any such effects in r and omised controlled trials .