No Link Between Bypass Surgery, Memory Loss
Underlying Heart Disease, Not Surgery, Linked to Subtle Mental Decline
Plaque Buildup Probably Cause of Mental Decline continued...
At four years, however, all three groups of heart patients scored significantly worse on tests of memory, decision-making, and visuospatial relations than the heart-healthy people.
“What matters is whether you have coronary artery disease, not what treatment you receive,” Selnes tells WebMD. “If your doctor recommends bypass surgery, you shouldn’t avoid it because of concerns about cognitive decline.”
Craig Blackstone, MD, PhD, a researcher at the National Institute of Neurological Disorders and Stroke who is on the ANA’s executive council, says the findings make sense.
People who have plaque buildup in the vessels leading to the heart probably have plaque buildup in the arteries leading to the brain that can lead to cognitive decline, he says.
Combination of Risk Factors Predicts Mental Decline
The researchers then performed a second study to determine which people with coronary artery disease are most likely to experience memory loss and other mental declines.
The study involved about 150 heart patients who underwent bypass surgery, 150 heart patients who took medication, and 69 people with no known risk factors for heart disease.
“As expected, people who were older and had less education experienced faster cognitive decline,” Selnes says. Having plaque buildup in all three of the main heart arteries and a history of irregular heartbeats known as atrial fibrillation also predicted faster memory loss and mental decline.
But people with coronary artery disease at greatest risk of mental decline were those with a combination of risk factors, including high blood pressure, a past stroke, and diabetes, the study showed.
Blackstone tells WebMD that many of the risk factors for coronary artery disease, such as high blood pressure and smoking, are also risk factors for plaque buildup in the brain and cognitive decline.
“If you do things to prevent one, you can prevent the other,” he says.