Study reveals how oestrogen protects women from high blood pressure

Oestrogen helps protect premenopausal women from hypertension by relaxing and widening blood vessels, according to new research examining why women develop high blood pressure less often before menopause.

High blood pressure, also known as hypertension, affects more than a billion people worldwide and is a leading cause of heart disease and stroke.

Premenopausal women are less likely to develop the condition than men or postmenopausal women, but the biological reason has been unclear.

Researchers used a mathematical model of the cardiovascular and kidney systems to analyse how oestrogen influences blood pressure.

The analysis found that oestrogen’s strongest protective effect comes from vasodilation, the process by which blood vessels relax and widen, helping blood flow more easily and lowering pressure in the arteries.

Anita Layton, Canada 150 Research Chair Laureate in Mathematical Biology and Medicine and professor of applied mathematics, said: “Oestrogen is often thought of only in terms of reproductive health, but it plays a much broader role in how the body functions.

“It affects how blood vessels respond, how the kidneys regulate fluids and how different systems communicate with one another.

“What we found is that its impact on blood vessels is especially important for regulating blood pressure.”

The findings may also have implications for treating women after menopause, when oestrogen levels naturally decline.

The model predicted that angiotensin receptor blockers, a common class of blood pressure drugs, could be more effective than another widely used treatment group known as angiotensin converting enzyme inhibitors in treating women with hypertension, even after oestrogen levels decline after menopause.

Layton said her team has spent years developing a mathematical model of women’s kidneys and the cardiovascular system, designed to explore how different biological mechanisms affect blood pressure.

The model allows researchers to test individual effects separately and examine how each influences the body.

“We can turn on one effect, then another, and see exactly how each one affects the body,” Layton said.

She added: “For too long, women’s health, especially older women’s health, has been overlooked by medicine.

“Understanding how age and sex affect the body and, therefore, treatment, is an equity issue.”