Assessing Benefits Of Reducing Cholesterol Levels Lower Than Current Recommendations

The new study, known as Treating to New Targets (TNT), is designed to resolve an important issue in the science of cholesterol lowering: How low should you go? Researchers aim to assess whether dramatically reducing LDL cholesterol levels can further cut the chance of death or heart attack in these patients.

Cardiologists have long warned that too much LDL cholesterol is bad for the body, in part because it contributes to atherosclerosis, also known as hardening of the arteries. Cardiovascular disease due to atherosclerosis is the leading cause of death and disability in the United States and Europe.

"We are seeing an increase in the prevalence of coronary artery disease,and the expectations are as our baby boomer population reaches middle ageafter the turn of the century the prevalence of coronary artery diseasewill double compared to 1985 numbers," said Dr. Carl J. Pepine, chief ofcardiovascular medicine at UF's College of Medicine. "Thus the results of this study could have extremely important implications for this segment of our population."

The five-year trial will involve about 8,600 patients at approximately 250sites in the United States, Canada, Europe, South Africa and Australia,making it one of the largest cardiovascular outcomes trials ever conducted with a cholesterol-lowering medication.

Patients will be treated at the Shands Cardiovascular Center at UF with the drug Lipitor, known generically as atorvastatin calcium. Lipitor's effect on cardiovascular disease and death is not known.

In general, the benefits of the class of drugs known as statins " has proven to be greater than our expectations," Pepine said. "It's turned out these drugs not only prevent death, but they also prevent myocardial infarction (heart attack), stroke, angina, the need for revascularization, and hospitalizations for unstable angina or heart failure, and they reduce the need for angiography," he said.

Current recommendations state an LDL cholesterol level of less than 130 isbest, while 130 to 159 is borderline high, and 160 or more puts people at increased risk for heart disease. A total cholesterol level of less than 200 is best. The study aims to determine whether patients benefit more when their LDL level is reduced to about 75 mg/dL versus 100 mg/dL.

Preliminary research suggests that lowering LDL cholesterol beyond currentclinical practice can yield even greater cardiovascular benefits, Pepine said. In other clinical studies, Lipitor reduced LDL cholesterol 39 to 60 percent in patients with elevated cholesterol who took it in dosages ranging from 10 to 80 milligrams. Possible side effects includeconstipation, flatulence, indigestion and abdominal pain.

Large epidemiologic studies have linked low cholesterol levels to reducedrisk of cardiovascular morbidity and mortality. Regional guidelines fortreating high cholesterol were developed based on these studies. In the United States, the National Cholesterol Education Program released an update in 1993 of its original 1988 guidelines, recommending a target LDL cholesterol of 100 mg/dL or less for patients with established coronary heart disease.

The trial is sponsored by Parke-Davis, a division of Warner-Lambert Co., and Pfizer Inc. Lipitor was discovered and developed by Parke-Davis and is marketed globally in collaboration with Pfizer.

Related research will investigate the clinical benefit of LDL cholesterolreduction in patients with acute unstable angina, patients referred forrevascularization procedures and those with type II diabetes.

Lipitor