Perspectives from the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial--Lipid Lowering Trial and the Anglo-Scandinavian Cardiac Outcomes Trial--Lipid Lowering Arm.

PURPOSE OF REVIEW: The design, process and outcomes are compared between two large clinical trials of LDL cholesterol reduction with statin treatment in patients with known high blood pressure. This new information is placed in the context of previous clinical trials of cholesterol reduction, which have provided analyses of sub-groups with high blood pressure.

RECENT FINDINGS: The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial failed to find a significant reduction of total mortality (primary endpoint), cardiovascular mortality or major cardiovascular events. This differed sharply from the Anglo-Scandinavian Cardiac Outcomes Trial, Lipid Lowering Arm, which was stopped before the planned termination due to a marked reduction (36%) in coronary death or myocardial infarction (primary endpoint). This trial also found significant reductions in stroke (27%) and separately, all major vascular events (21%). The two studies were similar in that they each contained over 10 000 participants with documented high blood pressure requiring drug therapy and they both used a fixed dose of a single statin. Pravastatin (40 mg/day) was used in the former and atorvastatin 10 mg/day in the latter. The major difference was that the control group in the Anglo-Scandinavian trial was treated with placebo with a double blind design whereas antihypertensive and lipid-lowering trial was open label with controls receiving usual care.

SUMMARY: The benefit of achieving and maintaining significant LDL cholesterol reduction in patients with high blood pressure was convincingly demonstrated in the Anglo-Scandinavian trial. The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial failed to achieve similar success due to use of a less effective drug and loss of the differential effect with increasing statin treatment in the usual care control group.