African Americans and Women Much Less Likely to Get Defibrillators
NEW ORLEANS, LA -- African Americans and women with
life-threatening heart rhythm abnormalities are significantly
less likely to receive implantable defibrillator devices
designed to convert lethal rhythms to normal heart rhythm,
according to a new analysis by Duke University Medical Center
After sifting through 64,936 cases of patients treated under
Medicare, the federal health insurance program for Americans
over the age of 65, the researchers found that African-American
Medicare patients received the devices at one-third the rate of
whites, while women received them at less than one-half the
rate of men.
This disparity is crucial because past clinical trials have
clearly demonstrated that defibrillators are superior to
existing medical treatments for these severe cardiac
arrhythmias, according to lead investigator, Duke cardiologist
Dr. Judy Battle.
Although their analysis was not designed to determine the
underlying reasons for this disparity, the researchers believe
that it is most likely a combination of factors, including
patient preferences and possibly physician bias.
"This is the first study to look at the racial differences
in the use of implantable defibrillators, and the results are
significant," said Battle, a researcher at the Duke Clinical
Research Institute (DCRI). "The data should provide the
springboard for continued research into better understanding
why these disparities exist and what we can do to close the
"All patients, whether they're black or white, male or
female, should be treated equally in receiving this life-saving
therapy," she said.
Battle prepared the results of her study for presentation
Monday at the 73rd annual scientific sessions of the American
Heart Association. The DCRI funded the study.
More than 350,000 deaths occur each year in the United
States due to sudden cardiac death, and one of the main causes
is ventricular tachyarrhythmia, in which the left lower heart
beats too fast. To control these incidents of "lethal rhythms,"
implantable cardioverter defibrillators (ICD) are placed within
a small pocket created in the body to deliver small electrical
shocks to the heart whenever the malignant rhythm occurs. In
most cases, the ICD returns the heart to its normal rhythm.
Since it has already been documented that African Americans
and women do not receive such invasive procedures as cardiac
catheterization, angioplasty or coronary artery bypass grafting
at the same rates as whites or men, Battle wanted to see if the
same trends held true for newer technology such as the ICD
In her analysis, Battle looked at Medicare patients who
received the device in 1991 and
1992. The patients studied were diagnosed with life threatening
heart arrhythmias and were seen at hospitals capable of
"Since we were using Medicare data, these low rates of ICD
placements in African Americans and women cannot be explained
by the differences in socioeconomic status, hospital facilities
or access to care," Battle said. "That's why it is so crucial
that we follow up on these findings. We know the disparity
exists, so now what are we going to do about it?"
Battle and her colleagues are beginning another analysis of
Medicare data from 1995 and 1996 to see if the situation is
She points out that while Medicare data have advantages in
providing a level playing field when comparing patients, they
do have limitations. The data are silent on one of the most
important aspects of health care - the patient-physician
"The reasons may be that patients prefer to take a medicine
instead of getting a procedure, or it may be a subconscious
bias decision on the part of the physician," she said. "We just
don't know. But we want to use this kind of information to move
the field forward."
Duke researchers have already demonstrated that African
Americans with heart disease receive fewer coronary artery
bypass surgeries and angioplasties than their white
counterparts. Another Duke study, published in May, showed that
some first- and second-year medical students already exhibited
biases based on patient race and sex.
Joining Battle in her analysis were DCRI colleagues David O.
Martin, Dr. Mark A. East, Dr. Lawrence H. Muhlbaier, Judy
Stafford, Dr. Jamie Jollis and Dr. Dan Mark.