The Hypertension Optimal Treatment (HOT) study was designed to determine if major cardiovascular outcomes are associated with target diastolic blood pressure (DBP) levels <=90 mm Hg, <=85 mm Hg, and <=80 mm Hg. More than 18,000 patients aged 50 to 80 years with hypertension and DBP between 100 and 115 mm Hg were randomized to achieve one of the three target DBP levels mentioned above. Antihypertensive therapy was started with the calcium blocker felodipine, and then additional treatment was given according to a 5-step regimen until the target DBP was achieved. In this study, patients were also randomized to receive low-dose aspirin (75 mg daily) or placebo. Patients were followed for an average of 3.8 years.
A total of 1,501 patients had diabetes at baseline, including 8% of patients in each of the three target DBP groups. In this subgroup of patients, the rate of major cardiovascular events (fatal and nonfatal myocardial infarction or stroke or all other cardiovascular deaths) declined in relation to the target DBP group (P=0.005 for trend). Notably, risk for these events in the <=80-mm Hg group was reduced by 51% relative to the <=90-mm Hg group.
Risk for MI (P=0.11 for trend) and stroke (P=0.34 for trend) was also reduced with lower target DBP levels. Risk for these events in the <=80-mm Hg group was reduced by 50% and 30%, respectively, relative to the <=90-mm Hg group. However, these risk reductions did not achieve statistical significance. Finally, cardiovascular mortality in the <=80-mm Hg groups was significantly reduced by 67% relative to the other DBP target groups (P=0.016 for trend).
These results demonstrate that lowering DBP to a target level <=85 mm Hg is associated with significant reductions in cardiovascular morbidity and mortality.

Hansson L, et al for the HOT Study Group. Lancet. 1998;351:1755-1762.