Women over 40 have been urged to check their blood pressure regularly to avoid heart attacks.
Researchers from the University of Bergen discovered that women who had mildly elevated blood pressure in their early 40s were twice as likely to have acute coronary syndromes in their 50s.
An acute coronary syndrome, also known as a heart attack, is when blood flow to the heart is suddenly reduced.
Blood pressure was measured in 6,381 women and 5,948 men, all aged 41, and any incidents of heart attacks were recorded over the following 16 years.
The researchers found that women who had mildly elevated blood pressure – with readings between 130-139/80-89 mmHg – had double the risk of acute coronary syndromes during their 50s, with no association between the two recorded in men.
Study author Dr. Ester Kringeland urged women to regularly have their blood pressure taken in order to reduce their risk, and those women who had any other underlying health conditions, such as obesity and diabetes, needed "more intense monitoring".
"Our analyses confirmed that mildly elevated blood pressure affects the risk of acute coronary syndromes in a sex-specific manner. The results add to emerging evidence indicating that high blood pressure has particularly unfavourable effects on women's hearts," she explained.
She also said women need to give up smoking and exercise more in order to reduce the risks.
"Women should know their blood pressure. To retain a normal blood pressure, it is recommended to maintain normal body weight, keep a healthy diet and exercise regularly. Furthermore, it is advisable to avoid smoking and excess consumption of alcohol and salt," Kringeland added.