BY SARAH OWENS
People who have a heart attack may have an increased risk over the next 35 years of developing vascular dementia, a decline in memory and thinking skills caused by a lack of blood flow to the brain.That's according to a study published online on October 12 in the journal Circulation.
Building on Previous Research
Previous studies showed an association between a heart attack and increased dementia risk, the study authors note. But those studies were small in scale, only found a weak or ambiguous association, or did not focus on a specific type of dementia.
The researchers wanted to understand the specific association between a heart attack and different types of dementia. They hypothesized that since a heart attack can lead to lower blood pressure and lower blood flow (or perfusion) in the brain, patients who have a heart attack may be more likely to develop vascular dementia.
Looking for Trends in a Large Database
Using the Danish National Patient Registry, a nationwide health registry of patients in Denmark, the researchers identified a total of 314,911 patients who had had a first heart attack in1980 and followed their health outcomes through 2012. They compared them with 1,573,193 healthy patients of the same age and sex.
Interpreting the Results
They found that about 9 percent of the patients who had a heart attack went on to develop dementia; of these, 2.8 percent developed Alzheimer's disease, 1.6 percent developed vascular dementia, and 4.5 percent developed other types of dementia.
People who had a heart attack did not have a significantly higher risk of developing all types of dementia compared to the general population, the researchers found. But they found that heart attack survivors had a significantly higher risk of developing vascular dementia. The risk was even higher among heart attack survivors who also suffered a stroke, experienced heart failure, or underwent coronary artery bypass grafting, in the first year after the heart attack.
The fact that a heart attack increased the risk only of vascular dementia, not Alzheimer's or other dementias, suggests that heart attack and vascular dementia may have shared risk factors, such as plaque buildup in the arteries, the study authors say. Also, treatments and complications of a heart attack – such as surgical procedures to treat it, or a stroke that causes a lack of oxygen to the brain – may play a role.
In the meantime, those who've had a heart attack or who are at risk for one can protect their hearts – and their brains – in these ways:
- Quit smoking.
- Keep blood pressure and cholesterol under control.
- Get blood sugar levels/diabetes under control.
- Follow a healthy, low-fat diet.
- Get plenty of exercise and maintain a healthy weight.
Learn more about vascular dementia in our story, "The Brain Needs Blood": bit.ly/NN-BrainNeedsBlood.