TUESDAY, April 8, 2008 (HealthDay News) -- A new study that weighed whether aggressively lowering cholesterol levels and blood pressure in people at high risk of heart disease is worth the effort did not produce a definitive answer to the question.
The research, which involved 499 American Indians with diabetes, found the strategy led to some improvements without producing dangerous side effects, said Barbara V. Howard, lead author of the report in the April 9 issue of the Journal of the American Medical Association.
"This is the first trial that really tested targeting," said Howard, a senior scientist with the Medstar Research Institute in Maryland. "Until now, clinical trials have meant taking a drug and escalating the dose and comparing the reduction in heart disease. Our goal was to target people at high risk and test lower targets for both risk factors hypertension and LDL cholesterol. What we showed is that you can reach those lower targets safely."
The improvement seen was a reduction in the thickening of the walls of the carotid artery, the main artery to the brain. However, no difference in the rate of adverse events was seen between those who had the most aggressive treatment and those who had standard treatment. "But there have been no trials where the carotid measurements did not correlate eventually with what happened in the endpoints," Howard noted.
The main conclusion of the trial is that "we see improvement with lower targets, but we need longer studies," Howard noted.
So, what should be done with the millions of Americans at increased coronary risk because, like the people in the trial, they have diabetes?
"What it says is that more aggressive targets than have been traditionally recommended can be achieved, can be achieved safely, and are associated with regression of plaque build-up in the carotid artery," said Dr. Mary J. Roman, a professor of medicine at Weill Cornell Medical College, and second author of the study.
To achieve the LDL cholesterol target, a blood level of 70, "I would still consider using ezetimibe [a second-line, cholesterol-lowering drug] in people who cannot tolerate statins and people who cannot achieve the target with maximum doses of statins or other medication," Roman said.
And while the incidence of side effects was higher in those treated aggressively for high blood pressure, Roman said, "aiming for that target has a beneficial effect. It is always easy to back off and not be as aggressive."
There was some disagreement on aggressive treatment of high blood pressure from Dr. Eric D. Peterson, a professor of medicine at Duke University, and author of an accompanying editorial.
"It would seem, based on what we have here, hard to justify ultraintensive hypertension reduction when we haven't shown benefit from a clinical viewpoint," Peterson said.
But with LDL cholesterol, "many arguments can be made for aggressive treatment in diabetic populations," he said.
The side effects of aggressive LDL cholesterol-lowering treatment are "minimal," Peterson said, and the addition of ezetimibe (Zetia) to statin treatment in some cases "seems to be reasonable."
"But ezetimibe has been a second-line agent," he said. "I would never use it as a first-line agent."
Ezetimibe has also been the subject of controversy in recent months as trials have started to show that adding the drug to statin treatment produces no benefit in reducing plaque build-up in blood vessels.
The links between diabetes and heart disease are outlined by the American Diabetes Association.