Transcript Cardiovascular Disease in Black Women

Cardiovascular
Disease in Black
Women
Rozann Hansford,
R.N.
MPH Candidate
Cardiovascular Heart Disease
Cardiovascular disease (CVD)
refers to a wide variety of heart and
blood vessel disorders including
CHD, HTN, stroke, rheumatic heart
disease
 Coronary Heart Disease (CHD)
refers to several disorders that
decrease blood supply to the heart
muscle

Pathophysiology of CHD
Atherosclerosis is the underlying
disease process
 Typically begins in childhood
 Slowly progressive,thickening of
the inner layer of the arteries walls
 Incidence increases with age
 Not an inevitable consequence of
aging

Pathophysiology of CHD
Disease progression starts with
fat deposition and advances to
fatty streaks with lipid core and
calcium deposits
 As atherosclerosis progresses,
arteries narrow enhancing
possibility of endothelial
disruption, hemorrhage and
occlusive thrombosis (3)

Pathophysiolgy of CHD
Contributing factors include
inflammatory, immunologic and
hemostatic processes involving
multiple systems and cellular types
 Persons most likely to suffer a
myocardial infarction have <50%
occlusion, not >70% occlusion as
previously thought

Biological differences between
blacks and whites?

It is not known whether cellular and
molecular mechanisms of atherogenesis
differ between races

Blacks with hypertension respond less to
angiotensin converting enzyme (ACE)
inhibitors

Blacks demonstrate greater fibrinolysis
when receiving tissue plasmin activator
(TPA) for myocardial infarction (4)
Epidemiology of CHD in
Black Women (US)
Black Americans experience a
higher morbidity/mortality
compared with other racial/ethnic
groups and have the highest age
adjusted CHD mortality (1). CVD
accounts for 41.6% of deaths in
black women
 CHD death rates are 67% higher
for black women compared to
white women

Epidemiology of CHD
in Black Women

CHD is particularly prevalent in black
women younger than 55 years old who
have 2.5 times the risk of CHD death
compared to white women (6).

Are black women deriving the same benefit
from estrogen as white women?

Black women have 2 times the rate of
angina compared with white women and
five times the rate of angina compare to
black men.
CHD Risk Factors in
Black Women
Framingham Heart
Study….defined and quantified
cardiac risk factors and related
finding to cardiovascular
outcomes
 Enrollment limited almost
exclusively to whites
 Should this data be generalized
to include all racial/ethnic mixes?

CHD Risk Factors in Black Women
Clinical Trials

CHS…Cardiovascular Heart
Study..enrollment limited to white
men and women

Charleston Heart Study, MRFIT study
and Chicago Heart Study…
enrollment limited to men
CHD Risk factors in black women
Clinical trials

Atherosclerosis in the Community
(ARIC) included large cohort of black
women
• Four communities in the US, 1987-1997
• Included 14,026 black and white men
• Included 10 years follow-up
• Hypertension a particularly strong risk
factor in black women
CHD Risk Factors in
black women

National Health and Nutrition
Evaluation Survey I (NHANES I)
• 14,000 black and white persons from
1982-1992
• Elevated systolic blood pressure and
smoking in black women predictive of
CHD
• Excess risk of CHD in black women
relates to higher levels of identified
risk factors
CHD Risk factors in black women
Smoking

Not specifically studied in black women

In women, first MI’s occur 19 years earlier
if woman smokes

May be a strong risk factor in black
women because of effects of co-morbidity
(black women have a high incidence of
HTN,diabetes and hypercholesterolemia
CHD Risk factors in black women
Hypertension
A major risk factor for the
development of CHD and stroke.
 Associated with pathologic changes
in the arterial walls and endothelium,
decreased of small peripheral
arteries, increased left ventricular
wall thickness and abnormal
diastolic function (15).

CHD risk factors in black women
Hypertension

Particularly strong risk factor in
Black women (ARIC) study
• Left ventricular hypertrophy is an
independent risk factor for
development of CHD
CHD risk factors in black women
Diabetes

Incidence of CHD is 2 to 4 times
higher in persons with Diabetes

Incidence of type II Diabetes is 9.1%
in black women compared with 4.5%
in white women
CHD risk factors in black women
Diabetes

Implicated as a possible etiology of
increased CHD incidence in young
black women
 Animal Studies suggest that
hyperglycemia and hyperinsulinemiainsulin may prevent the cardiovascular
effects of insulin
 Black women have a higher incidence
of obesity and diabetes relative to white
women,protection from CHD that sex
usually provides may not be as strong
in black women
CHD risk factors in black women
Syndrome X
Syndrome X…cumulative effects of
hypertension, glucose intolerance and
dyslipidemia
 Associated with a higher cardiovascular
mortality
 Has a synergistic effect on atherogenesis
 Seen more often in black women than
other racial/ethnic mixes

CHD risk factors in black women
Obesity
Approximately 75% of African
American women are obese, more
than any other racial gender mix
 Body Mass Index (BMI), body fat
distribution and central obesity are
all predictive of CHD risk in women
 Major cause is inactivity

CHD risk factors in black women
Hypercholesterolemia


Incidence of elevated cholesterol
is 20% in black
women..relationship to CHD not
studied in black women
In black men, relationship of
elevated cholesterol to CHD
development is confusing, may
have implications for black
women
CHD risk factors in black women
Hypercholesterolemia

In whites, higher socioeconomic is
associated with higher HDL’s..the
reverse is true in black men

Black men have higher levels of
lipoprotein but these levels are less
predictive of CHD in black men
compared to white men
Socioeconomic factors
CHD in black women results from
a complex interplay between
established risk factors, access to
health care, behavioral and coping
mechanisms and socioeconomic
status
 Differences in access to care and
economic factors may play an
important role

Socioeconomic factors

Because black women do not access
health care facilities as often as white
women, community based
interventions at churches, work places
and schools may be useful for
prevention
 Heart, Body and Soul partnership
between Clergy and Johns Hopkins
University minimizes barriers
associated with mistrust of health
personal
Research needed!!!
Insufficient data available for
resolving questions related to
racial/gender comparisons
 Need to determine if differences,
clinical paradoxes and
inconsistencies are related to
chance findings, artifacts in
reporting, environmental
differences or biological
differences

Research Needed!!!
Data already collected needs to
be pooled and examined; a first
step would include a national
screening policy
 Culturally validated data tools
needed
 Need to study efficacy of
prevention strategies

Conclusions

Most large scale clinical trials to date
have excluded black women. Results
have been generalized to include black
women and this may be very
misleading

Small studies, incidental findings,
responses to some meds and animal
research hint at the possibility of
biological differences between black
women and other racial/ethnic mixes
Conclusions
Black women tend to get CHD 10
years earlier than white women.
The reasons for this though
hypothesized, have not been
established.
 Hypertension appears to be the
single most important risk factor
for the development of CHD black
women.

Conclusions

The excessive incidence of CHD in
black women is likely due to a
complex relationship between
social, behavioral, genetic and
economic factors. Teasing out the
contributions of these factors so
that appropriate public health
measures can be implemented is
likely to be a very difficult task!
References

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 2. Gillum RF, The epidemiology of
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 3. Ross R. The pathogenisis of
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
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