UCSF-led study finds racial disparity in use of key treatment for stroke

By Jennifer O'Brien

Researchers led by UCSF scientists are reporting that a highly effective clot
busting drug for stroke is significantly underutilized in all patient
populations at U.S. academic medical centers, and is strikingly underutilized
in African Americans.

The study, reported in the May issue of Stoke: Journal of the American Heart
Association, showed that among 1,195 stroke patients seen at 42 academic
medical centers around the country, only 49 patients, or 4.1 percent, received
the drug, known as tPA. Of the 285 African Americans in the study, only three
(1.1 percent) received tPA compared with 42 (5.3 percent) of the 788
Caucasians. In other words, African Americans were one fifth as likely to
receive the drug as Caucasians.

The racial discrepancy persisted after adjusting for age, gender, insurance
status, and severity of stroke.
Importantly, most of the patients in the study were not eligible to receive
the drug, as it must be delivered within three hours of onset of symptoms and
most patients did not reach a hospital emergency department during that time.
In addition, a small number of patients were not medically eligible for the
risky therapy.

This fact—that most people do not reach the hospital in time to receive the
drug - is one of the key findings of the study, and indicates that society must
do a better job of educating all people about the early warning signs of stroke
and the importance of getting to the hospital in time to receive early
treatment, says lead author S. Claiborne Johnston, MD, MPH, UCSF assistant
professor of neurology.

But an even more revealing, and troubling, aspect of the study, says Johnston,
is the magnitude of the racial discrepancy in the use of tPA.

“Society as a whole, not just the medical community, is responsible for the
significant racial discrepancy this study reveals,” says Johnston. “Factors
contributing to the problem might include the need for more education on
symptoms of stroke within the African American community or greater distrust of
the medical system by African Americans. It’s also possible that patients are
refusing the drug, as it is considered an aggressive, high-risk therapy, and
that this isn’t documented. Another possible factor is racial prejudice, though
in this case it would most likely be not that doctors care less about African
Americans, but that they may have preconceived notions about whether African
Americans are willing to accept aggressive, risky treatments.”

To tease out whether African Americans and others were not getting the drug
because they were poor candidates or because doctors were not offering it, the
researchers examined the records of a subgroup of patients who had been deemed
medically eligible to receive tPA. Among these 189 patients, only 20.6 percent
received the drug. Only three of 36 African Americans (8.3 percent) received
the drug compared to 34 of 138 (24.6 percent) of Caucasians. Thus, in this
eligible group, African Americans were one third as likely to receive tPA as
those who were Caucasians.

The racial discrepancy persisted after adjusting for age, gender, insurance
status, and severity of stroke.

While the numbers of Latinos, Asians and Native Americans seen in the study
were small, indicating that they were seen less often at these centers, the
rates of use of the drug in these groups were not significantly different from
those of Caucasians.

To evaluate regional differences in tPA delivery, the authors also performed a
larger but less detailed confirmatory study that included 8,608 stroke patients
treated at 66 academic medical centers around the country. Notably, for reasons
not yet clear, the ethnic disparity was not seen in medical centers in the
Southeastern United States.

But in the Northeast, less than one percent of African Americans received tPA,
while 2.3 percent of Caucasians did. In the Midwest and West, the rates were
2.1 percent and 1 percent for African Americans and 4.8 percent and 3 percent
for Caucasians.

“Though a more detailed analysis of factors predicting tPA treatment is
required, we have to consider the possibility that racism contributed to the
disparity in treatment,” report the University of California San Francisco and
Yale University School of Medicine researchers in their paper.

“Giving tPA is considered high-risk, so there are many factors that physicians
are weighing when they decide whether or not to utilize it,” says Johnston.
“But we took these variables into consideration in the subgroup we studied and
still couldn’t rule out the possibility that racism was a key factor.
Practitioners need to examine their own motivations when withholding this
proven therapy. Just being educated to the fact of this discrepancy will be
important for leading physicians to fix it.”

Johnston said he suspects that at least part of the discrepancy is explained by
the possibility that some physicians have preconceived ideas that African
Americans’ are more averse to risky medical procedures. The study did not
examine this possibility, but it has been reported in the use of some
aggressive procedures for cardiovascular disease and cancer.

An accompanying editorial in the journal urges healthcare professional to pay
serious attention to the results, particularly because African Americans have a
greater risk of stroke than Caucasians and are more likely to die from stroke.

Notably, the type of medical insurance coverage a patient had was independently
associated with tPA treatment. After adjustment for ethnicity, age, sex, stroke
severity and ethnicity, those patients with Medicaid or without insurance were
one ninth as likely to receive tPA as those with private medical insurance.

The researchers cited numerous studies in their paper reporting that African
Americans are less likely than Caucasians to receive a number of aggressive
medical therapies, including coronary artery angioplasty, bypass surgery and
tumor resection of colon and lung cancer. (Socioeconomic status also influences
utilization of medical services, they say, but the effect of ethnicity persists
after correction for income.)

But reductions in ethnic disparities at academic medical centers have been
documented during the last decades, says Johnston, indicating, he says, that
there is reason to hope that there will be improvements in stroke treatment.

In January 2000, former U.S. Department of Health and Human Services Secretary
Donna E. Shalala and Surgeon General David Satcher released Healthy People
2010, the nation’s health goals for this decade. One of two major themes of
Healthy People 2010 is the elimination of racial and ethnic disparities in
health status.

Intravenous tPA, or tissue-type plasminogen activator, is the first proven
therapy for acute ischemic stroke. It acts by dissolving blood clots blocking
either the arteries leading to the brain or those in the brain itself. Approved
by the Food and Drug Administration in 1996, its use has been recommended in
published neurology consensus guidelines. The study examined medical records
established during six months in 1999.

tPA is considered a high-risk therapy,  but the majority of patients will
benefit from the drug, says Johnston. Still, he says, the drug is associated
with an increased chance of bleeding into the brain, and this makes some
physicians uncomfortable and more resistant to using the drug.

Patients who would be ineligible for treatment would include those who arrived
at the hospital more than three hours after the onset of symptoms, were already
receiving blood-thinning treatment, had acute high blood pressure, internal
bleeding, evidence of extensive tissue damage from the stroke (detected through
a CT scan), or a minor or improving medical condition.

The researchers focused their study on academic medical centers because the
institutions were most likely to have the necessary resources to support tPA
administration, including physicians with stroke expertise and sophisticated
interpretation of head CT scans. Given the resources of academic medical
centers and the fact that they generally offer the most aggressive treatments,
nonacademic centers probably use the drug even less frequently, the researchers

Co-authors of the study were Lawrence H. Fung, BA, a visiting medical student
at UCSF; Leslie A. Gillum, MD, a UCSF neurology resident; Wade S. Smith, MD,
PhD, UCSF professor of neurology and director of the UCSF Stroke Service;
Lawrence M. Brass, MD, neurology, epidemiology and public health, and Judith H.
Lichtman, PhD, associate research scientist, both of Yale University School of
Medicine and Andrew N. Brown, MD, MPH, formerly of UCSF.

The study was funded by the National Institutes of Health.