According to a new American Heart Association study, the connection between heart and brain health is linked more closely than ever. The very same risk factors that make heart disease the leading cause of death in the United States have unfortunately increased the risk for stroke, Alzheimer's, and dementia.

In particular, the study highlighted atrial fibrillation, an irregularity of the heartbeat, as the major risk for these cognitive impairment conditions.

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After the age of 81, 1 in 10 people have this rhythmic disorder, according to world-renowned cardiologist and director of preventive medicine at the Palm Beach Cardiovascular Clinic in Florida Dr. Chauncey Crandall. He is also the editor of the monthly newsletter Heart Health Report.

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"It really begins in the 60s, but it is a rhythm problem that causes changes. One main change is that the function and strength of the heart is reduced by 20%. And when that happens, we lower the perfusion to the brain and vital organs, which can set up memory issues and problems," Crandall says.

He also stressed the additional problems of potential blood clots that can form inside the heart, break loose, and travel to the brain, causing both strokes and silent strokes that patients aren't aware of. Over time, these can slowly destroy parts of the brain, impacting memory and behavior.

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Still, there are steps one can take to prevent atrial fibrillation, according to Crandall, which include maintaining good health by adopting dietary restraints into your food intake to help maintain an ideal body weight, exercise, better sleep, and decreasing stress.

"If you have hypertension, get treated for it. If you're overweight, lose weight and often your blood pressure will improve," says Crandal. "Those would be simple, commonsense keys that will give you a long life and prevent disorders like atrial fibrillation."

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