March 23, 2009 -- Heart disease patients who achieve normal blood pressure and very low cholesterol levels with aggressive drug therapy do better than patients who achieve only one of these goals, new research suggests.
Using ultrasound to identify plaque buildup within the artery walls as a measure of disease progression, Cleveland Clinic researchers found that patients who were able to get their low-density lipoprotein (LDL) cholesterol below 70 mg/dL and their systolic blood pressure (the top number in a blood pressure reading) below 120 with medication had less plaque buildup over the course of the study than patients who reached just one or neither of these targets.
The findings highlight the importance of treating all risk factors for heart disease progression, rather than targeting just one, study co-author Stephen J. Nicholls, PhD, tells WebMD.
“I think sometimes we aggressively try to manage one risk factor and lose sight of the fact that we need to manage all of them,” Nicholls says. “If we want to get the greatest bang for our buck in terms of treatment, we need to focus on all risk factors.”
‘Lower Is Better’ for LDL
Earlier research by Nicholls and Cleveland Clinic colleagues helped establish the “lower is better” strategy for controlling LDL cholesterol with statin drugs like Lipitor, Crestor, and Zocor in patients at high risk for having heart attacks, strokes, or other cardiovascular events.
As a result of their work and the work of others, national treatment goals for LDL were recently lowered to less than 100 for patients with established heart disease and less than 70 for the highest-risk patients.
Current guidelines identify a resting systolic blood pressure of 120 or below as normal; a reading of 140 or above is high.
A reading of between 120 and 140 is considered "prehypertension.”
There are no widely accepted guidelines for treating patients who fall into this category, but the new research suggests that maybe there should be, Nicholls says.
“We know that (heart attack and stroke) risk starts to increase at about 115,” he says. “This study suggests that treating to lower blood pressure levels is probably beneficial, but we need clinical trials to test this.”
The monitoring revealed that:
- Patients who achieved LDL levels below 70 and systolic blood pressures of below 120 had the slowest progression, as measured by increase in plaque volume.
- Those with LDL levels below 70 and systolic blood pressures above 120 had more rapid plaque buildup, but these patients fared slightly better than patients with LDL levels above 70 and systolic blood pressures over 120.
- Patients with LDL levels above 70 and systolic blood pressures above 120 had the most rapid increase in plaque volume.
“With the powerful statin drugs we have today, we see a lot of patients who reach their cholesterol goals but not their blood pressure goals,” study co-author Steven E. Nissen, MD, tells WebMD. “This suggests that we need to aggressively target blood pressure and cholesterol to stop disease progression and even reverse it.”
More Study Needed
The study appears in the March 31 issue of the Journal of the American College of Cardiology.
In an accompanying editorial, UCLA heart disease researchers Jonathan Tobis, MD, and Alice Perlowski, MD, urged caution in interpreting the study.
The researchers note that a direct relationship between plaque progression as measured by the ultrasound technique used in the study and hard clinical events like heart attack and stroke has not been established.
They write that clinical trials examining these hard endpoints are needed to confirm that very aggressive treatment of cholesterol and blood pressure is beneficial for patients with established heart disease.
Cardiologist James T. Dove, MD, agrees.
Dove is a clinical professor of medicine at Southern Illinois School of Medicine and the immediate past president of the American College of Cardiology.
“In high-risk patients, very aggressive treatment might well be the best approach, but the operative phrase is ‘might well be,’” he tells WebMD. “There is a downside to very aggressive treatment that needs to be considered, especially with blood pressure.”
Dove says clinical trials are definitely needed to determine if the “lower is better” treatment strategy results in better clinical outcomes for patients with established heart disease.
“The ‘lower is better’ approach may be the way to go, but we need more information to be sure about that,” he says.