Women have a greater risk than men of developing atrial fibrillation – when you look at people of the same height. So far, many studies have shown that men are more prone to this type of cardiac arrhythmia than women. According to the new study, however, this result is due to the fact that men are larger and heavier than women on average and the risk of the disease increases with height and weight.
Other risk factors are age, ethnic origin or high blood pressure, but they do not change the gender balance. The study by the group led by Christine Albert from Cedars-Sinai Medical Center in Los Angeles (California, USA) is in the journal JAMA Cardiology appeared.
It has been a mystery to medical professionals why men appear to be at greater risk of developing atrial fibrillation. “However, our study surprisingly indicates that if a man and a woman are the same height, the woman has a higher risk of developing atrial fibrillation,” Albert is quoted as saying in a statement from her institute.
In patients of the same height, women have a 39 percent higher risk
This has fundamentally changed the approach to finding the cause of gender differences: “Instead of asking why women are protected, we now have to try to understand why women are at greater risk.” The analysis of the research team showed: In men and women of the same body size, women have an up to 39 percent higher risk of developing atrial fibrillation. If you also take body weight into account, the risk is even 49 percent higher.
Atrial fibrillation is the most common cardiac arrhythmia, affecting one to two percent of the general population. The atria of the heart do not beat in their natural rhythm, but move uncontrollably. Due to this irregular heartbeat, the blood is not transported evenly through the heart cavities. This can cause clumps, so-called thrombi, to form. If these thrombi are brought into the systemic circulation with the blood flow, vessels can become blocked. As a result, organs are reduced or not supplied with blood at all. A thrombus that gets into the bloodstream of the brain can thus cause a stroke.
Symptoms of atrial fibrillation can include tachycardia, an irregular pulse, inner restlessness or even dizziness and sudden loss of consciousness. However, the disease often goes unnoticed by those affected. If atrial fibrillation is detected, it depends on the individual risk and the person’s symptoms as to whether therapy is necessary. On the one hand, the increased frequency with which the auricles beat is treated, but also the risk of the formation of thrombi. In special cases, the heart can be brought back into its natural rhythm with medication or electricity.
More than 25,000 women and men without cardiovascular disease between November 2011 and March 2014 were included in the current study. The men were 50 years or older, the women 55 years or older. 51 percent of the study participants were women, 20 percent black. They were followed for between 5.1 and 5.7 years.
For most physical characteristics and risk factors, there were only very small differences between the sexes. However, when the researchers kept body weight or height constant in the analysis, women were found to have a greater risk of atrial fibrillation. “Atrial fibrillation is a disease that we want to prevent, regardless of gender,” emphasizes Albert. The medical community should take the results as an opportunity to talk to all patients, whether male or female, about the risk of atrial fibrillation.
With material from dpa