Strokes are more common and serious in women – here’s how to understand your risk

Each year, more than 6.6 million people worldwide die from strokes, and researchers caution that the incidence is increasing, especially in young and middle-aged people and in low- and middle-income countries. In a report published in October, researchers predicted that stroke deaths would increase by about 50 per cent, reaching 9.7 million deaths annually in 2050.

Strokes occur when the flow of oxygen and nutrients to the brain is cut off. This can happen when blood vessels get weak and eventually rupture under pressure, known as a hemorrhagic stroke. More commonly, clots or plaque can block blood vessels to the brain; this is known as an ischemic stroke. Both types of stroke can lead to permanent damage or death.

When people survive a stroke, they often face long-term disability, an increased risk of depression, memory problems and more. But the burden of the disease can be averted and the global disparities reduced, authors of the report said.

Many of the risk factors for stroke that are becoming more common across the globe – high blood pressure, elevated cholesterol and smoking – are also easily treatable. Still, stroke risk can vary by population, and women in particular have some additional risk factors that may need monitoring.

In the United States, 795,000 people have a stroke every year, and about 55,000 more women than men will experience one. Women are also more likely to die from strokes compared to men.

Some of this higher risk can be attributed to women’s longer life expectancy, said Dr Daniel Hermann, an interventional cardiologist at Memorial Hermann Health System in Houston.

“Age is a huge risk factor for stroke,” Dr Hermann said. As people get older, they are more likely to experience high blood pressure, high cholesterol, plaque buildup, wear and tear of their arteries and poorer blood sugar control, all of which contribute to strokes, Dr Hermann said.

For women, the period of biological change that occurs during perimenopause and menopause is also critical. Many women start to develop blood pressure issues during this transition. Experts believe this is because the hormone oestrogen may help keep blood vessels relaxed and balance cholesterol levels. When the body stops producing estrogen, the incidence of stroke and other heart diseases goes up.

Studies confirm this link in women who experience menopause earlier than usual. Compared with women who undergo menopause between the ages of 50 to 51, those who experience premature menopause before they turn 40, or early menopause between the ages of 40 and 44, have a 98 per cent and 49 per cent higher risk of stroke, respectively.

But excess estrogen, in the form of hormone therapy, may have the opposite effect. “There is data that oestrogen replacement in perimenopause and menopause can increase the risk of stroke and so can progesterone,” said Dr Marion Buckwalter, a professor of neurology and neurosurgery at Stanford University Medical Center. Research suggests the benefits of menopause hormone therapy only outweigh the risks if taken at a younger age or closer to menopause, when the hormone levels would more closely align with what your body used to produce.

Some evidence suggests that women who use certain types of hormonal birth control are also more likely to have a stroke, especially if they have high blood pressure, smoke or experience migraines, all of which can increase risk. A few studies have suggested that women who undergo infertility treatment and transgender women who take oestrogen for gender affirmation have a higher risk of stroke as well.

Women also face unique risk factors during and immediately after pregnancy. Because the volume of blood increases during pregnancy and then rapidly reverses after a woman gives birth, her risk of blood clots also increases, Dr Buckwalter said. If a woman gains excessive weight during pregnancy or develops pre-eclampsia or gestational diabetes, that can also increase her risk of clots and stroke later in life.

Black women in the United States are more likely to have a stroke than any other group of women. They also are more likely to have strokes at younger ages and to have more severe strokes. Many factors may drive this increased risk, including a lifetime of racial discrimination; poorer access to health care to manage underlying conditions; and a higher general incidence of high blood pressure, elevated cholesterol and obesity, as well as genetic conditions like sickle cell anemia.

HOW CAN WOMEN PREVENT STROKE?

The best way to lower your risk is to start by keeping track of and treating high blood pressure. “You’d probably reduce strokes by about half if you treated all blood pressure,” Dr Buckwalter said.

Get regular wellness exams starting in your 20s so that you can catch blood pressure issues, high cholesterol or diabetes early on.

Be aware of your family history of heart disease and stroke and use the American Stroke Association’s assessment form to check your risk. Talk to your doctor about alternatives to birth control pills if you are high-risk, and about closer monitoring of blood pressure during certain stages of life like pregnancy and menopause.

Starting in your 60s, it can also be a good idea to ask for an ankle-brachial index test, to check for plaque buildup in your leg arteries. And use the letters in FAST to remember warning signs of a stroke: Face drooping or numbness; arm weakness; speech difficulty; and time to call 911 (995 in Singapore). Getting medical help quickly can save your life and prevent serious disability.

By Knvul Sheikh © The New York Times Company

The article originally appeared in The New York Times.