A new study by Imperial College London has found multiple reproductive factors are linked to a higher risk of cardiovascular disease in women.
Researchers have provided evidence to show a causal relationship between sex-specific factors and cardiovascular disease in women. This study has identified potential ways to mitigate this increased risk.
The study is the most comprehensive analysis to date of reproductive factors specific to women and their links to a range of cardiovascular diseases, including atrial fibrillation, coronary heart disease, heart failure, and stroke. The researchers now hope their findings will help doctors to better understand and monitor risk factors of cardiovascular disease in women and intervene where needed.
The study is published in the Journal of the American Heart Association.
Analysing data from over 100,000 women
Researchers from Imperial’s National Heart & Lung Institute, University of Cambridge and Yale School of Public Health analysed genetic data linked to women’s age at first birth, their number of live births, their age at their first period (menarche), and their age at menopause. They looked at previous studies involving more than 100,000 women.
Previous observational research has identified that some reproductive factors are associated with cardiovascular disease in women in later life, but these studies are limited as they have been unable to support a causal relationship.
The team used a statistical technique called Mendelian Randomization which showed a link between the genes that predict reproductive factors and the risk of multiple cardiovascular diseases. This type of analysis enables researchers to look past factors such as diet and physical activity level that can complicate the data.
The link between reproductive factors and cardiovascular disease in women
The researchers found that earlier first birth, a higher number of live births, and earlier menarche were associated with a higher risk of atrial fibrillation, coronary artery disease, heart failure, and stroke in women. However, no association was found between the age of menopause and cardiovascular disease in women.
Furthermore, the increased risk for earlier menarche resulted from this factor being associated with women having a higher body mass index (BMI). This could mean that lowering BMI could help reduce this risk. The increased risk for an early first birth could be partly reduced by tackling cardiometabolic risk factors, such as BMI and high blood pressure.
Dr Maddalena Ardissino, the lead author of the study, from the National Heart and Lung Institute at Imperial College London, said: “Women are often mischaracterised as being at low risk for cardiovascular disease, leading to delays in diagnosis. Even when they are diagnosed, they tend to receive less targeted treatment than men.
“This study shows a clear link between reproductive factors and cardiovascular disease. This doesn’t mean that women should worry if they’ve had their period at a young age, or if they had an early first birth. Our research shows that the additional risk of cardiovascular disease can be minimised if traditional risk factors like BMI and blood pressure are well-controlled. These findings highlight the need for doctors to monitor these risk factors closely in women and intervene where needed.”
Further research is required to understand the extent of the relationship between reproductive factors and cardiovascular disease in women.