Gene Found to Increase Risk of Mental Decline after Heart Surgery

In a recent research study presented on USNews.com, a gene has been discovered to increase the possibility of experiencing mental decline after heart surgery.  It has been calculated that between 30-50% of people who had heart surgery showed a decrease in mental health after the surgery.  The reason for this decline in mental function hasn’t been known until now.  It has been thought that it was a side effect of the surgery and anesthesia or a neurological disorder the patients had prior to the surgery.  The gene responsible for the decrease in mental function after heart surgery is the APOE4 gene.  The APOE4 gene stands for apolipoprotein E4 and this gene is involved with cholesterol metabolism and inflammation.  Also, the APOE4 gene has been linked to an increased risk of developing Alzheimer’s.  The scientists made this discovery after assessing the mental capabilities of 233 elderly, white patients before heart surgery and 5 years later after the surgery.  The results of the study concluded that those elderly with the APOE4 gene had long-term memory loss, attention problems, and difficulty understanding spoken or written words five years after having heart surgery.  Dr. Karsten Bartels, who was involved with the study, summarized the findings by stating “Our findings suggest that the long-term cognitive decline previously seen after surgery is related more to the patient’s genetic makeup than to the surgery itself.”  He even went on to say that if doctors know patients have the APOE4 gene, they can make the necessary precautions to protect the patient’s brain after surgery as well as helping their patients make better-informed decisions knowing the risk of having decreased mental function after heart surgery.  The findings of this study were recently presented at the annual meeting of the American Society of Anesthesiologists in San Francisco and have not yet been published in a peer-reviewed medical journal.  

            I thought that this article was extremely interesting and very important.  I had no clue that a gene could increase the risk of developing a decrease in mental function after heart surgery.  If anything, I would think that the surgery itself or the anesthesia would have been the cause of the mental decline in patients.  The importance of this discovery is that doctors can now first find out if their patients possess the APOE4 gene and then can assess the patient’s risk of developing cognitive problems after surgery.  Also, doctors can help patients make better-informed decisions regarding surgery and possibly seek alternative surgeries or treatments that can avoid the chance of developing cognitive problems later on.  Plus, this study finding can help doctors develop strategies or methods to protect their patient’s brain after surgery especially if heart surgery is the option a patient has.  One question that came to mind while reading this article was how are people of different races affected after heart surgery if they do possess the APOE4 gene?  The article stated that the study was conducted on 233 elderly, white patients, but do people of other races experience mental decline after heart surgery as well?