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Sex differences in ‘normal’ blood pressure and associated CVD risk
Women have a lower ‘normal’ blood pressure range
compared to men and this is linked to risk for each specific
cardiovascular disease (CVD) type, including heart attack,
heart failure, and stroke, a large study from the Smidt Heart
Institute at Cedars-Sinai Medical Centre found.
Currently, established blood pressure guidelines state that
women and men have the same normal healthy range of
blood pressure. But this research shows there are differences
in normal blood pressure between the sexes.
‘Our latest findings suggest that this one-size-fits-all
approach to considering blood pressure may be detrimental
to a woman’s health,’ said Dr Susan Cheng, associate
professor of cardiology and director of the Institute for
Research on Healthy Aging in the Department of Cardiology
at the Smidt Heart Institute and senior author of the study.
‘Based on our research results, we recommend that the
medical community reassess blood pressure guidelines that
do not account for sex differences.’
For years, 120 mmHg has been considered the normal
upper limit for systolic blood pressure in adults. Persistent
elevations above this limit amount to hypertension, which is
well known as the key risk factor for common cardiovascular
diseases, such as heart attack, heart failure, and stroke.
In their newest study, Cheng and her research team
examined blood pressure measurements conducted across
four community-based cohort studies, comprising more than
27 000 participants, 54% of whom were women.
In doing so, the research team identified that while 120
mmHg was the threshold of risk in men, 110 mmHg or lower
was the threshold of risk in women. Systolic blood pressure
levels that were higher than these thresholds were associated
with risk for developing any type of cardiovascular disease,
including heart attack, heart failure and strokes.
Investigators also found that women had a lower blood
pressure threshold than men for risk of each specific
cardiovascular disease type, including heart attack, heart
failure and stroke. ‘We are now pushed to rethink what
we thought was a normal blood pressure that might keep
a woman or a man safe from developing heart disease
or stroke,’ added Cheng, who also serves as director of
cardiovascular population sciences at the Barbra Streisand
Women‘s Heart Centre and is the Erika J Glazer chair in
women’s cardiovascular health and population science.
These findings build on past research led by Cheng
suggesting women’s blood vessels age faster than those of
men. Cheng’s research, published last year, confirmed that
women have different biology and physiology from men
and also explained why women may be more susceptible of
developing certain types of cardiovascular disease and at
different points in life.
With both the 2020 study and in their latest work, Cheng
and her team compared women to women and men to men,
rather than the common model of comparing women to men.
‘If the ideal physiological range of blood pressure truly
is lower for females than males, current approaches to using
sex-agnostic targets for lowering elevated blood pressure
need to be reassessed,’ said Dr Christine Albert, chair of the
Department of Cardiology at the Smidt Heart Institute. ‘This
important work is far reaching and has numerous clinical
implications.’
As a next step, researchers plan to study whether women
should be treated for hypertension when their systolic blood
pressure is higher than 110 mmHg, but still lower than the
systolic measurement of 120 mmHg for men.
Source:
Medical Brief 2021