In a hale and healthy heart dwells a young and active brain, suggest U.S. researchers, who recently found that poor ಕಾರ್ದಯಾಕ್ output results in brain volume loss.
A team of scientists from Boston University revealed that people with 'sluggish hearts' pump out less blood and thus have "older" brains on MRI (Magnetic Resonance Imaging) scans than the ones who keep their heart in best form.
Study findings
The study observed 1,500 people, between 34 to 84 years of age, whose brain and heart MRI scans averred that the normal human brain shrinks as people get older with age.
According to researchers, people with the high cardiac index or those with the highest blood flow from their heart, have more brain volume that generally indicates a healthier brain.
But a relatively low cardiac output ages the brain by nearly two years on average, they stated.
Researchers observed the link even in young participants who were not suffering from cardiovascular diseases, such as heart failure or coronary heart disease and found the same results as in elderly people.
They said, “as the brain ages, it begins to atrophy (shrink), has lesser volume, and can often lead to dementia.”
Dr Angela Jefferson, associate professor of neurology at Boston University School Medicine, said, “These participants are not sick people. A very small number have heart disease. The observation that nearly a third of the entire sample has low cardiac index and that lower cardiac index is related to smaller brain volume is concerning and requires further study."
Decreased cardiac index leads to dementia?
Several theories have been put forward explaining why reduced cardiac index might affect ಬ್ರಿನ್ health.
Cardiac index is the measure of blood the heart pumps out relative to body size.
For instance, a study suggests that decreased volume of blood pumped might reduce flow to the brain, providing less oxygen and fewer nutrients needed for brain cells, which ultimately leads to its shrinkage.
Dr Clinton Wright, a brain and memory expert from the University of Miami, said, "Whether lower cardiac index leads to reduced brain volumes and accelerates neurodegeneration on an eventual path to dementia is not yet clear.”
The team of researchers will now study the individuals in the trial to see if and how variations in brain affect memory and cognitive abilities over time.
The study appears in 'Circulation: Journal of the American Heart Association.'