ALLHAT: still providing correct answers after 7 years.

PURPOSE OF REVIEW: The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) is re-evaluated considering information from recent subgroup and exploratory analyses, other new clinical trials, and meta-analyses. The ALLHAT analyses specifically emphasize heart failure findings, results in Black participants and those with chronic kidney disease, selection and doses of thiazide and similar diuretics, and the association of antihypertensive drug use with new-onset diabetes and its cardiovascular consequences.

RECENT FINDINGS: The initial ALLHAT conclusion, that thiazide diuretics are superior to angiotensin-converting enzyme inhibitors (ACEIs), calcium antagonists (CCBs) and alpha-blockers in preventing one or more major clinical outcomes, including heart failure and stroke, and unsurpassed in significantly preventing any cardiovascular or renal outcome, has been further validated for patients with diabetes, renal disease, and/or metabolic syndrome. The evidence is even more compelling for Black patients. New-onset diabetes associated with thiazides did not increase cardiovascular outcomes. The diuretic was superior to all in preventing heart failure with preserved left-ventricular ejection fraction (LVEF) and similar to the ACEI in preventing heart failure with impaired LVEF. It was also unsurpassed in preventing atrial fibrillation.

SUMMARY: The totality of evidence re-affirms the initial ALLHAT conclusion that thiazide and similar diuretics (at evidence-based doses) are the preferred first-step therapy in most patients with hypertension.