ALLHAT: setting the record straight.

The findings of the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) have generated worldwide reaction from clinicians and researchers, including a recent commentary in this journal. Such response was expected for a trial of ALLHAT's size and scope, especially since its results challenged some widely held beliefs. This paper reviews key aspects of the ALLHAT design, analyses, findings, and conclusions to provide a perspective on the commentary about the trial's results and implications for clinical practice. Several of the most frequent comments regarding the study's results are addressed, particularly with respect to heart failure and diabetes outcomes. Responses to these comments reinforce the investigators' original conclusion that thiazide-type diuretics should remain the preferred first-step drug class for treating hypertension and should generally be a part of any multidrug regimen.