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WASHINGTON – In one of the largest analyses of its kind,
Duke University Medical Center researchers have found that the
use of beta blockers for patients with heart failure or left
ventricular dysfunction (LVD) has more than doubled from 1995
to 2002.

While the researchers say that the steady increase in beta
blocker use over time is encouraging, they emphasize that more
effort is needed in the patient-health care provider
relationship to ensure greater compliance long term. This
emphasis on compliance is important, the researchers continued,
because numerous recent clinical trials have shown that beta
blockers can cut the relative risk of death by approximately
one-third for this group of patients.

The Duke researchers found in their analysis of 8,914 heart
failure/LVD patients entered into the Duke Databank for
Cardiovascular Disease (DDCD) that beta blocker usage increased
from 29 percent in 1995 to 62 percent in 2002. However, when
the researchers looked at individual heart failure patients'
use of beta blockers over at least two annual follow-up
evaluations, only 43 percent of patients consistently took the
medication. In these patients who consistently took the
medication, beta blockers bestowed a 41 percent relative
mortality risk reduction. The magnitude of this benefit on
survival is consistent with findings in randomized clinical
trials. .

Judith Kramer, M.D., of the Duke Clinical Research
Institute, presented the results of the Duke analysis May
17, 2004, at the American Heart Association's 5th scientific
forum on Quality of Care and Outcomes Research in
Cardiovascular Disease and Stroke.

"Many trials conducted since the 1980s have shown that beta
blockers can reduce the risk of having a heart attack," Kramer
said. "However, as late as the early-1990s, doctors were
trained not to prescribe beta blockers for their heart failure
patients. Since beta blockers reduce the force of contraction
of the left ventricle, it was thought these drugs would harm
these patients.

"However, the first of several definitive clinical trials
reported in 1996 that beta blockers improved the survival for
heart failure patients," Kramer continued. "As our study shows,
the acceptance of evidence-based treatment is difficult when
the new evidence is a 180-degree change from previous
practice."

Beta-blockers are a class of drugs that blunt the
stimulatory effects of epinephrine and norepinephrine, the
so-called "fight-or-flight" hormones. By blocking the effects
of these hormones, beta-blockers reduce the stress on the
heart, and during exertion, they limit the increase in heart
rate and so reduce the demand for oxygen.

In order to determine the usage rates of beta blockers among
heart failure patients since the first pivotal clinical trial,
Kramer consulted the DDCD, which has been collecting detailed
clinical information on all its cardiac catheterization
patients since 1969. Every Duke heart patient with documented
coronary artery disease is contacted once a year following
discharge from the hospital: since 1995, researchers also began
asking detailed questions about medication use.

In addition to analyzing the compliance trends, the
researchers looked at the specific beta blocker taken. In 1995,
the generic atenolol was used by 55 percent of patients, but
had dropped to 37 percent by 2002. In contrast, beta blockers
that have been proven in randomized clinical trials to provide
a survival benefit for patients with heart failure, such as
cardvedilol and metoprolol succinate, increased from 0 percent
to 10 percent and 3 percent to 28 percent, respectively, over
the same period.

"The patterns of drug use show that there is a growing use
of evidence-based medicines in the treatment of heart failure,"
Kramer said. "This pattern of drug usage suggests we are moving
in the right direction despite the increased cost associated
with the medication."

In fact, a recent study done by the Duke Centers for
Education and Research on Therapeutics (CERTs), demonstrated
that beta-blockers can reduce the overall costs associated with
managing a patient with heart failure, Kramer said.

While atenolol is less expensive, its effectiveness for
heart failure patients has not been proven by a specific
clinical trial, as it has been for reducing blood pressure. She
added that there likely won't be such a clinical trial, since
generic formulations of atenolol are widely used and such a
trial would be very expensive to conduct.

Those factors predicting a higher rate of beta blocker usage
included patients who received an angioplasty or coronary
artery bypass surgery, or who had a stroke.

"These are dramatic events that appear to catch patients'
attention and make them more likely to listen to their
physicians," Kramer said. "These types of events also provide
an opportunity for physicians to start patients on
evidence-based medicines like beta blockers."

Factors predicting lower usage included increasing age,
presence of chronic obstructive pulmonary disease (COPD),
asthma or the use of digoxin. "Given the established data that
the elderly benefit just as much from beta blockers, we are
concerned by the association between older age and lower
likelihood of taking beta blockers," she said.

For Kramer, communication and the personal contact between
patients and the health care team could be the most effective
way of increasing beta blocker use among heart failure
patients.

"It is my belief that the personal approach can be the best
way to support patients and help them overcome the barriers
they face, whether they are financial, medication side effects
or education," she said.

To that end, Duke is planning other efforts to better
understand the issues surrounding long-term patient compliance
with evidence-based medicines, including a pilot project that
will link Duke cardiologists and pharmacists with physicians
and pharmacists out in the community. The goal is to create
communication links with patients to overcome barriers, she
said.

It has been estimated that there are 5 million Americans
with heart failure, with 550,000 new cases diagnosed each year
and more than 53,000 deaths annually. The cost of treating
heart failure in 2004 has been estimated at $25.8 billion.

Kramer's analysis is part of the CERTs demonstration
program, a national initiative to conduct research and provide
education that advances the optimal use of therapeutics,
including drugs, medical devices, and biological products. The
program, which consists of seven centers and a coordinating
center, is administered as a cooperative agreement by the
Agency for Healthcare Research and Quality (AHQR), in
consultation with the U.S. Food and Drug Administration (FDA).
Duke is the coordinating center for the cardiovascular
CERTs.

Other members of the Duke team were Anita Chen, Bradley
Hammill, Elizabeth DeLong, Ph.D., Nancy Allen LaPointe,
Pharm.D., Lawrence Muhlbaier, Ph.D., Charles McCants, Jr., and
Robert Califf, M.D.