A family physician questions the conclusions from ALLHAT.

A key Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) conclusion is that thiazide diuretics should be preferred for first-step antihypertensive therapy. ALLHAT was not a monotherapy trial, and rational drug combinations were discouraged by study design in the lisinopril limb. The ALLHAT conclusion that recommends chlorthalidone for initial hypertension therapy seems unjustified because ALLHAT was not a trial that initiated therapy for hypertension. ALLHAT was not of sufficient length to detect the poorer outcomes that are inevitable with increased rates of diabetes in the chlorthalidone limb. The heart failure subset analysis was not prospectively established. ALLHAT was not designed to make the conclusions claimed by its authors.