A new study published in the Journal of the American Heart Association has shown that a heart abnormality called atrial cardiomyopathy may increase the risk of developing dementia by 35%.
The study included over 5,000 older adults in the U.S. who were participants in the Atherosclerosis Risk in Communities study, and the study follow-up period was more than 30 years. Participants in the study who had atrial cardiomyopathy, or functional or structural abnormalities in their left atrium (one of the chambers of the heart), had a 35% increased risk of developing dementia compared to those without those abnormalities. Atrial cardiomyopathy is also associated with a higher risk of having atrial fibrillation or stroke, which are both associated with greater risk of developing dementia. However, when the researchers controlled for atrial fibrillation and stroke, atrial cardiomyopathy still increased dementia risk by 31% and 28%, respectively.
The authors of the study noted that their results do not imply causality, only correlation. However, their results still show the importance of minimizing cardiovascular risk factors to minimize the risk of developing dementia.
Heart disease is tied to the risk of developing dementia in part because of vascular dementia, which occurs when blood flow to the brain is decreased and causes damage to brain tissue. After Alzheimer’s disease, vascular dementia is the second most common type of dementia. The incidence of vascular dementia is likely to rise in the coming years due to the combination of an aging population and increasing rates of heart disease, obesity, and diabetes. The ways to minimize the risk of developing vascular dementia are very similar to minimizing the risk of developing heart disease, including not smoking, exercising regularly, maintaining a healthy weight, and controlling blood pressure.