Smoking, diabetes and high blood pressure increase the risk of a heart attack more in women than in men, new research from The George Institute for Global Health at the University of Oxford has found.
Published in the British Medical Journal, the study of 472,000 participants, aged 40-69, found that smoking, diabetes, and high blood pressure increased the risk of heart attack in men and women. However, it also found that women were at "excess risk", says senior cardiologist at The George Institute's Sydney headquarters, Dr Clare Arnott.
"Overall, more men experience heart attacks than women. However, in women there are certain factors that appear to be more powerfully associated with heart attack risk than in men, giving women a so-called 'excess risk'," says Dr Arnott.
"These factors include high blood pressure, diabetes, and cigarette smoking."
The research found that female smokers had almost 3.5 times the risk of heart attack than non-smoking females, as compared to 2.2 times in male smokers. When comparing men with high blood pressure to women with high blood pressure, women had an 80% higher risk of having a heart attack than men. Type I diabetes was associated with an almost three times higher risk, and type II diabetes a 47% higher risk in women than in men.
Dr Arnott, who established the Women's Heart Clinic at Sydney's Royal Prince Alfred Hospital, says as men and women are physiologically different, "it therefore stands to reason that [health] conditions may present differently".
"Women are more likely to present with 'non-chest pain' symptoms when having a heart attack as compared to men," she says. "These have been described as 'atypical symptoms' because typical symptoms have previously been defined based on men."
Heart attack occurs when blood flow decreases or stops to a part of the heart, causing damage to the heart tissue. Patients experiencing heart attack may have symptoms of chest pain, shortness of breath, and pain in their arms, back, neck, jaw or stomach. Additional symptoms, more common in women, are unusual tiredness, dizziness, cold sweats, and nausea or vomiting.
Heart disease – the narrowing or blocking of blood vessels that can lead to heart attack, chest pain (angina) or stroke – is a leading cause of death in women in Australia. In fact, women are almost three times more likely to die of heart disease than breast cancer.
Risk factors are conditions that increase the chance of developing a disease. They can be modifiable – meaning you can lower your risk by, for example, eating a healthy diet and not smoking – or non-modifiable, which means they cannot be changed (eg, family history). Around 90% of women in Australia have at least one heart disease risk factor.
Ensuring blood pressure, cholesterol and glucose levels are regularly checked, and not smoking are ways to reduce the risk of heart attack. Knowing your risk factors and addressing those that are modifiable is central to reducing heart attack risk and improving overall health, says Dr Arnott.
"For example, while a woman who currently smokes has 3.5 times the risk of a heart attack, an ex-smoker has only 1.3 times the risk of a lifelong non-smoker," she says.
The George Institute's findings have major implications for pregnant women who develop high blood pressure, diabetes, or pre-eclampsia during their pregnancy.
Every year, it is estimated that 30,000 women in Australia are diagnosed with pre-eclampsia or hypertension during pregnancy and research shows that these women are at increased risk of heart disease post-pregnancy.
"We now know that the risk of high blood pressure is four times [that], and heart disease twice that, of women who did not experience these conditions in pregnancy," says Dr Arnott.
"Similarly, between 5-10% of pregnant women will develop diabetes during their pregnancy, and this will increase their risk of type 2 diabetes and heart disease later in life."
"The good news is that pregnancy provides an opportunity because it enables doctors to identify women early and potentially modify their risk".
For more information on heart health, go to our section on Cardiovascular health.