Duke University Medical Center researchers believe their findings could help physicians identify patients at risk of suffering mental decline after heart surgery and raises the possibility that these patients could be treated with drugs that are known to dampen the inflammatory response.
Six years ago, the Duke researchers demonstrated that 42 percent of patients who underwent coronary artery bypass surgery had measurable cognitive decline five years after their procedure. Since that finding, the team has been investigating possible reasons for this decline.
The researchers selected known variations in 37 genes that previous studies had implicated in various impairments of cognitive and mental function. When they looked at more than 500 heart surgery patients and correlated cognitive decline with the patient’s genetic makeup, they discovered that patients with two specific variants were less likely to have problems with areas of cognitive function such as memory, attention and concentration.
“While bypass surgery has saved millions of Americans with coronary artery disease, many patients and families find that cognitive decline after surgery has reduced their quality of life,” said Duke cardiothoracic anesthesiologist Joseph Mathew, M.D., lead investigator of the study reported online Tuesday, May 1, in the Journal of the American College of Cardiology. The study was supported by the National Institutes of Health and the American Heart Association.
“The two gene variants we found were involved in some manner with the inflammatory system, raising the possibility that therapies given during surgery aimed at the controlling the inflammatory response would be protective,” Mathew said. “Also, our results provide additional evidence for a genetic basis for the cognitive deterioration seen after heart surgery.”
The researchers found that patients with variants in genes for C-reactive protein and P-selectin were less likely to suffer cognitive decline than were patients without the variants. C-reactive protein plays an important role in the body’s initial response to injury, and studies have shown that high levels of the protein put patients at higher risk for cardiovascular disease and stroke. P-selectin is a molecule that helps recruit circulating white blood cells to the site of an injury.
For their analysis, the researchers gave 513 heart patients at Duke University Hospital a battery of cognitive exams before heart surgery and then six weeks later. They found that patients with the variation of the C-reactive protein gene were 20.6 percent less likely to suffer mental decline, and patients with the P-selectin variant had a 15.2 percent risk reduction. The incidence of deficit in patients with both gene variants was 17 percent compared to 43 percent in patients who had neither variant.
Furthermore, patients with the two gene variants had significantly lower levels of C-reactive protein in their bloodstream and lower P-selectin expression, and the researchers said this factor may provide a biological basis for the protective effect they observed.
“Although we have made significant progress in minimizing the adverse events related to cardiac surgery, little progress has been made in reducing postoperative cognitive decline,” said Mark Newman, M.D., chairman of anesthesiology and senior member of the research team. “While we know that there are many factors involved in this phenomenon, the results of this study provide insight into the genetic factors that influence cognition and may translate into more precise identification of at-risk patients.”
Coronary artery bypass grafting surgery is performed more than 600,000 times a year in the United States for the treatment of coronary artery disease. Typically, surgeons use pieces of blood vessels from other parts of the body to “bypass” clogs in coronary arteries, thereby restoring blood flow to the heart.
Richard Merritt | EurekAlert!
Switch-in-a-cell electrifies life
18.12.2018 | Rice University
Plant biologists identify mechanism behind transition from insect to wind pollination
18.12.2018 | University of Toronto
Researchers from the University of Basel have reported a new method that allows the physical state of just a few atoms or molecules within a network to be controlled. It is based on the spontaneous self-organization of molecules into extensive networks with pores about one nanometer in size. In the journal ‘small’, the physicists reported on their investigations, which could be of particular importance for the development of new storage devices.
Around the world, researchers are attempting to shrink data storage devices to achieve as large a storage capacity in as small a space as possible. In almost...
The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.
Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...
What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...
A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.
The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...
A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.
Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...
12.12.2018 | Event News
10.12.2018 | Event News
06.12.2018 | Event News
18.12.2018 | Materials Sciences
18.12.2018 | Physics and Astronomy
18.12.2018 | Physics and Astronomy