The ALLHAT study: results and clinical implications.
The Antihypertensive Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) just published,1 is the largest clinical trial so far conducted. Under the auspices of the National Heart Lung and Blood Institute (NHLBI), it included over 40 000 high-risk hypertensive patients (aged 55 years or older) who were followed over 5 years (with the exception of the doxazosin treatment arm, which was discontinued prematurely due to a higher incidence of heart failure).2 It included 33 357 patients who were randomized to treatments, including chlorthalidone 12.5–25.0 mg/day ( n  = 15 255), amlodipine 2.5–10 mg/day ( n  = 9048) and lisinopril 10–40 mg/day ( n  = 9054). The doses of these drugs were increased until a blood pressure goal of < 140/90 mmHg was achieved. In addition, other drugs could be added to the baseline treatments such as atenolol (25–100 mg/day), reserpine (0.1–0.2 mg/day) or clonidine (0.1–0.3 mg bid) at the discretion of the investigator. Also, hydralazine 25–100 mg bid could be added as a step 3 drug. The pre-specified primary outcome of this trial was fatal coronary heart disease or non-fatal myocardial infarction combined. Secondary outcomes included all-cause mortality, fatal and non-fatal stroke, coronary artery disease, peripheral vascular disease, heart failure, end-stage renal disease and cancer. The mean age of the study population was 67 years, 47% were women, 35% were Black, 19% were Hispanic and 36% were diabetic.

The major clinical findings of this large study were as follows.

Some 60% of treated hypertensive patients reached a blood pressure goal of < 140/90 mmHg, compared to current estimates of 34%.3 This despite the protocol limitations on proper drug combination, on which I will comment later.

There …