By Samantha (Sam) Leslie and Isabelle (Izzy) O’Toole, VI Form

Alzheimers: The Nature vs. Nurture Debate

Editor’s Note: This study was made possible by the Class of 1986 V Form Fellowship. At their 25th reunion, the Class of 1968 created a fund to provide grants to V Form students for independent study during the school year or, more commonly, during the summer between V and VI Forms. Their intent in establishing this fund was to reward independent thinking, ingenuity, and planning and to encourage the student exploring non-traditional fields of inquiry or using non-traditional methods of investigation.

Introduction:  
Through talking with various doctors, caretakers, and volunteers, we learned the different ways that a person can delay or progress Alzheimer’s disease (AD).  One of the first people we talked to was a man who had years of volunteer and caretaker experience, and his biggest takeaway was that each case is different, so it is hard to tell what will work with each patient.  We heard similar answers as we talked with various doctors and caretakers, but some of the more common ways to delay Alzheimer’s include diet, exercise, and pharmaceuticals. There are also many ways in which a person can progress Alzheimer’s such as drugs and alcohol, sleep patterns, and diet (Rowlett).  Regardless of these lifestyle choices, some people will still get Alzheimer’s at an early age or old age, and it will progress faster in certain patients. Having a good caretaker and staying social is a big key to staying happy and connected after an Alzheimer’s diagnosis (Lynch).

Sleep Pattern: Progress
Sleep is an essential part of a human’s daily cycle, and it is highly suggested that someone sleep for at least eight to nine hours for the best cognitive brain function. A poor sleeping pattern can increase a person’s risk of getting Alzheimer’s disease. If one has a hard time falling asleep or staying awake, the risk increases. While sleep is an amazing regenerator for the human body, but too much sleep can be detrimental to one with AD. Sleeping in and sleeping for more than nine hours increases one’s risk for AD relative to someone who sleeps for the preferred six to nine hours. In addition to the amount of sleep one gets, disruptions in one’s sleep pattern can also progress AD. Sleep disruptions that include someone else’s snoring or loud neighbors can lead to negative effects on the brain. When someone is disrupted from a full night’s sleep, this causes a poor sleeping pattern which may lead to cognitive decline and memory loss, but if one has one of these problems and decides to use sleeping pills, the pills can actually increase one’s risk for the disease as well. Sleeping pills can cause cognitive and memory problems but this more frequently occurs in people who take the pills for short term use. The likely reason for this occurrence is because of the quick change in lifestyle which those with long term usage do not experience. 

Drugs and Alcohol: Progress
Illicit drugs and heavy alcohol consumption have negative effects on the human brain. Drugs and alcohol can cause cognitive impairments, especially with chronic use over a long period of time. Alcohol consumption does not have a direct link to dementia when it is used in moderation, but heavy use over many years can cause damage to the brain, which increases a person’s risk for dementia or Alzhiemer’s. Alzheimer’s Disease International and the National Institute for Health and Care Excellence performed a study wherein they reviewed drinking patterns, and they came to the conclusion that if a person binge drinks or drinks heavily in a short period of time they increase their risk for dementia in later life by a substantial factor. Drugs, similar to alcohol, have a high risk of cognitive impairment; excessive use of illicit drugs can impact one’s mental state and cognitive function which have links to dementia and AD.

Smoking: Progress
Despite the warnings of medical professionals and health statistics, smoking remains prevalent across many age groups. Smoking is a severe contributor to illness; the act of smoking cause issues to the lungs and heart, but one may obtain a vascular disease from the secondhand smoke of a close relative or friend. Smoking and exposure to secondhand smoke not only leads to vascular problems and cancer but can also progress Alzheimer’s. An article from the Mayo Clinic notes, “research has shown that the same risk factors associated with heart disease may also increase the risk of Alzheimer’s disease” (Mayo Clinic). An increased risk of vascular problems brought on by smoking, such as strokes and brain bleeds, increases the risk for dementia and AD. The cigarette smoke can also result in an increase in inflammation as well as oxidative stress. These both cause damage to the brain and increase the risk of developing AD. 

Exercise: Delay
Exercise is an important daily activity that reduces the risk of Alzheimer’s disease.  It is recommended that a person exercise for 30 to 60 minutes a day, which may reduce the risk of AD by 50% as exercise helps improve brain function by cleaning out some of the toxins.  Exercise throughout a person’s life can help reduce AD in their future, but physical activity is also important after the diagnosis as it still helps to delay the progression (“What is Alzheimer’s?”).  In a person with an AD mutation, exercise can help promote nerve growth while restoring the hippocampus region, which is responsible for making new memories. As memory loss is a hallmark for AD, exercise can delay the disease in both early and late onset cases.  In early onset, there were lower tau protein build ups in people who exercised for at least 150 minutes a week (Med News Today). In late onset, exercise had similar positive impacts as it did with early onset. In both, physical activity can also help protect against oxidative stress, which causes damage to cells.  In AD there can occur an excess of oxidative stress that causes increased damage to the neurons. If the neurons are more resistant to the stress due to regular activity, there will be a delay in the onset. Exercise throughout one’s lifetime can reduce the risk of developing AD or delaying its onset, but continuing to partake in physical activity is just as important after the diagnosis as it can reduce the symptoms and delay the progression.

Diet: Delay
Diet is an important aspect in reducing or delay Alzheimer’s disease, and there are multiple diets that can help reduce the risk.  One diet that can be beneficial to some with Alzheimer’s is a low copper diet. AD can make it harder to metabolize copper, which progresses the disease, so a low copper diet may help slow the onset of AD (Squitti et al.).  Because there are so many different mutations that lead to AD, not every person will benefit from a low copper diet, but it could help many people with the alteration to their metabolism. About 75% of a person’s copper comes through food intake while the remaining 25% is through drinking water, so by eating low copper foods, an individual’s overall copper intake will decrease.  Most of the patients that can benefit from this diet fall under the late-onset category. Non-Cp copper was found in increased levels during the autopsy of an AD brain. When there is too much copper, it can trigger the amyloid cascade, which causes the beta-amyloid to build up, creating plaques and disrupting the neural pathways. If there is less copper to trigger the amyloid cascade, there will be less build up of the plaques, and there will be a subsequent delay to the memory loss and other symptoms of AD.  A second beneficial diet is an unsaturated fat diet. Polyunsaturated and monounsaturated fats have been shown to reduce the risk of AD by 70 to 80%. This percent did vary based on age and race, but in all there was a clear sign of decreased risk for AD with an unsaturated fat diet. Although unsaturated fats are beneficial, it was also discovered that unsaturated fats do not need to be eaten in excess to have a positive impact. Although only two diets were discussed here, there are many more that can be beneficial to different people as each person has a slightly different experience with AD. Regardless, diet plays a major role in delaying AD.

Pharmaceutical Drugs: Delay
The FDA has approved multiple drugs that help to delay Alzheimer’s disease, the most common ones being cholinesterase inhibitors and memantine. Both drugs aid in the reduction of AD symptoms, but they do not fully prevent brain decay. Cholinesterase inhibitors are most useful in patients with early to moderate symptoms, and this drug helps with memory, reasoning, and language (Lynch). The drug works by preventing the breakdown of acetylcholine, which is a neurotransmitter that carries a signal from a neuron to a cell.  If the acetylcholine cannot break down, it stays in the synaptic gap, which means that it can continue to create an action potential in the cells and promote brain activity. Although the deterioration of the brain still occurs, the symptoms are much more manageable with the help of cholinesterase inhibitors. The other most common drug is memantine, which regulates glutamate activity in the brain. This class of drug is more commonly used for moderate to severe AD, and it helps patients with memory, language, and judgement. Memantine functions by attaching to glutamate receptors, which block the glutamate.  If the ligand-gated channel cannot open, less calcium will go into the brain cells, which can cause a chemical imbalance. Both of these drugs help a patient with AD manage day-to-day life by helping to delay and lessen the symptoms; however, neither is a full cure.

Conclusion:
There are many ways to progress or delay Alzhiemer’s disease based on one’s diet, exercise, alcohol consumption, and sleep pattern, but these can have a limited amount of persuasion for the time someone may get the disease. Through talking with many specialists and caretakers, we learned genetics plays the biggest factor in AD onset, but there are still many other factors that could delay or progress it. Nurture plays a crucial role and can help slow the progression of AD significantly after after a diagnosis. If someone prioritizes getting sleep, having committed caretakers, and exercising daily, they can not only have a longer, healthier life, but ultimately limit the progression of AD. Although environmental and lifestyle factors may help, they will not be the final determinant of AD’s progress or delay. Genetics and one’s environment work together decide someone’s fate, so it is crucial to be aware of both factors.

Sam Leslie is a VI form day from Sudbury, Massachusetts.  She enjoys history and biology, and her favorite activities are squash and soccer.

 Izzy O’Toole is a VI form boarding student from Weston, Massachusetts. Her favorite subjects are history and math, and she loves playing soccer and lacrosse