The study, published online in the journal Circulation, found individuals with decreased heart function were two to three times more likely to develop significant memory loss over the course of the study.
 

"Heart function could prove to be a major risk factor for dementia and Alzheimer's disease," said lead researcher Angela Jefferson, director of the Vanderbilt Memory & Alzheimer's Center.
 

"A very encouraging aspect of our findings is that heart health is a modifiable risk. You may not be able to change your genetics or family history, but you can engage in a heart healthy lifestyle through diet and exercise at any point in your lifetime."
 

The findings are based on information culled from the Framingham Heart Study, an effort that began in 1948 to identify risk factors for heart disease. More than 1,000 study participants were tracked for 11 years to compare cardiac health and the development of dementia.
 

Over the study, 32 participants developed dementia, including 26 diagnosed with Alzheimer's disease.
 

"For the average adult, the brain accounts for 2 percent of overall body weight but receives as much as 15 percent of blood leaving the heart,” Jefferson noted. “If there are changes in the heart's ability to pump blood, the brain is resilient and does a great job at regulating blood flow to maintain a consistent level to support brain tissue and activity. But as we age, our vessels tend to be less healthy. They become less adaptable to blood flow changes, and those changes may affect brain health and function.”
 

She added: "At present, there is no proven method for preventing dementia or Alzheimer's disease. But leading a heart healthy lifestyle could help. When 30 percent of the population is exposed to a potential risk factor, like low cardiac index, that suggests it may be of significant public health concern."