Neurodegenerative diseases such as dementia affect 50 million people worldwide [1]. As the elderly proportion of the global population is expected to grow at a rapid rate due to increasing life expectancies, more and more individuals are at risk of related diseases. To address this looming health crisis, both everyday citizens and physicians must be equipped with all of the available knowledge on the subject.
Most people are not aware of the difference between dementia and Alzheimer’s, but it is fairly simple to understand. Dementia is an umbrella term for multiple chronic illnesses that develop into more serious conditions, which include neurodegeneration and memory loss. Alzheimer’s is only one of the many illnesses that fall under this umbrella; it is also the most common chronic disease that leads to dementia making up 50-70% of all related cases [1]. The second most common illness is vascular dementia, which accounts for 33% of all cases and causes memory loss in patients with diabetes or people who are at risk of having a stroke.Other forms of dementia consist of frontotemporal dementia, Parkinson’s disease dementia, and more [2].
The impacts that Alzheimer’s-related dementia can have on one’s life are quite radical. The disease causes one to become extremely dependent on others to do simple tasks for them. In many cases, it is observed that Alzheimer’s patients often refuse to take showers or to keep themselves clean. The disease can also cause changes in the affected person’s relationships and family role. If the affected person was hypothetically in charge of the family’s finances and other sensitive information, this dynamic will have to come to an end. The affected person can often grow more irritable and less understanding with those around them. The patient might also begin to forget the names of family and friends, further distancing themselves from the people in their vicinity. Eventually, even basic skills used in the context of daily life (e.g. conversation, emotional regulation, memory recall, etc.) are lost, thereby changing all aspects of the patient’s relationships, personal finances, and overall behavior.
When lowering the chances of contracting Alzheimer’s due to aging, one must understand exactly why and how dementia is developed. Although not every single cause of the condition is known, there are several certain determinants that are widely accepted by the scientific community to lead to dementia. According to the Mayo Clinic, one of the widely accepted causes, especially for Alzheimer’s patients, is genetic triggers [3]. In many cases, the genes related to dementia can be passed down from parent to child. Whether or not these genes become expressed later in life is all up to chance; however, if the child does have them, the risk of contracting dementia greatly increases. While several genes are involved in this increased risk, one gene that stands out is apolipoprotein E4 (APOE4). This gene leads to decreased longevity and is also associated with cardiovascular disease and cognitive decline [4].
The pervasiveness of Alzheimer’s is another risk factor. A study conducted by the Alzheimer’s Association shows that the number of people affected by the disease in 2006 was 26.6 million [5]. Since then, there has been a steady and noticeable rise in cases as $156 billion is spent annually in fighting this disease worldwide. The study finds that by 2050, 1 in 85 people will be afflicted with this disease due to greater life expectancies. This projection is dismaying and should be responded to with a considerable level of concern given the severity of a disease like Alzheimer’s. Although family history and genetics are both a factor in being affected by the disease, this statistic shows the pervasiveness of Alzheimer’s and gives cause to eradicating unhealthy habits that may lead to the activation of APOE4.
Despite the bleak future set out by the threat of Alzheimer's, there are both mental and physical methods available to mitigate the spread of the disease. For example, the latest dementia-related research has revealed that a key method of delaying Alzheimer's is through maintaining brain function. According to Dr. Brendan J. Kelley, one of the driving forces behind increased risk of Alzheimer’s is mental deterioration caused by age [6]. To prevent this process of cognitive decline, specialists suggest trying specific exercises that are proven to promote mental fitness. These exercises consist of things like learning a new instrument or language, sudoku, reading, and learning a new cooking recipe. Most of these exercises contain something in common that is also very important in developing a cognitive defense system against Alzheimer’s. These activities force the person doing them to learn something new. The individual might already have good, healthy habits and daily activities, but when it comes to fighting against neurodegenerative diseases, it is important to support the growth of new nerve cells and communication between already existing nerve cells through consistently taking on new pursuits [7]. In fact, learning new skills is the only way to generate new nerve cells and to have those cells communicate with each other.
In addition to maintaining one’s mental capabilities, there are other methods that can help in countering Alzheimer’s. More specifically, physical activity should be used alongside cognitive exercises to delay the onset of the disease.
Although there are several well-known, established examples of how to maintain one’s cognitive function, the term “physical activity” can be vague. To clarify what it means to be physically active, Dr. Jonathan Graff-Radford explains anything that increases the heart rate in one’s body is enough to count as exercise [8]. However, effective exercise usually increases an individual’s resting heart rate, which is around 80-100 beats per minute and brings it to 150-170 beats per minute. Physical activity can prevent mood-related conditions like depression and also lead to the optimization of the immune system. If exercise is responsible for all of these benefits for one’s general health, then the effects of physical fitness on dementia must be additionally investigated.
In a study conducted by the Cleveland Clinic, 454 volunteers were given accelerometers to track their physical activity over a span of 20 years [9]. During this time period, each individual took an annual test that tested their memory and cognition. The volunteers who demonstrated better bodily fitness usually scored higher than those who didn’t remain as physically active. At the end of the study, the researchers reported that consistent exercise leads to a 31% lower risk of contracting dementia. This is because physical exertion increases blood flow to the organs and reduces the levels of stress hormones, both of which help counteract breakdown of brain function. Unfortunately, there is an evident flaw within this experiment; the people who exercised during this 20 year span already had an established workout routine in their life. The question remained of whether or not volunteers who had been generally inactive before the study could actually benefit from changing their lifestyles to be more physically active. As a result, the American Academy of Neurology conducted a study to prove his hypothesis that a healthy diet and a regular exercise routine for a minimum of 150 minutes per week is enough to lower the risk of developing Alzheimer’s in individuals with sedentary habits [10]. The researchers’ results found that those who strictly followed the diet without any exercise did not improve in the performance of his tests. However, the individuals within the study who followed the physical activity parameters without as large of an emphasis on diet improved their overall health significantly. The study found that the best an individual could possibly do for themselves when preventing Alzheimer’s is coupling a healthy diet with physical exercise. However, partaking in a physical exercise routine without a diet has a larger role in preventing the disease than strictly following a healthy diet without the implementation of exercise. This conclusion proves that exercise and physical activity has a clear impact in slowing down the effects of cognitive decline no matter when an individual begins to exercise.
The established argument is clear: physical activity must be encouraged alongside mental exercises to optimally fight against the development of Alzheimer’s. Unfortunately, despite the benefits of consistent cognitive function and exercise, both methods do not perfectly prevent dementia. They are simply stopgap measures that are used while researchers work to find other, more effective methods of counteracting this disease. However, given all of the research, it is clear that we must not ignore their effects on the body, especially for a condition as devastating and common as dementia.
[1] “Alzheimer's Disease Facts and Figures.” Alzheimer's Association. 2012. https://pubmed.ncbi.nlm.nih.gov/22404854/
[2] Feldman, Howard H., Claudia Jacova and Alain Robillard. “Diagnosis and Treatment of Dementia,” Canadian Medical Association Journal, no. 7 (March 2008). https://doi.org/10.1503/cmaj.070798
[3] “Alzheimer’s Disease.” Mayo Clinic. 2020. https://www.mayoclinic.org/diseases-conditions/alzheimers-disease/symptoms-causes/syc-20350447
[4] Smith, Jonathan D. “Apolipoprotein E4: An Allele Associated with Many Diseases,” Annals of Medicine, no. 32 (2000). https://doi.org/10.3109/07853890009011761
[5] Brookmeyer, Ron and Nada Abdalla. “Estimation of lifetime risks of Alzheimer’s disease using biomarkers for preclinical disease,” Alzheimer’s and Dementia, no. 8 (May 2018). https://doi.org/10.1016/j.jalz.2018.03.005
[6] Kelley, Brendan J. and Ronald C. Petersen. “Alzheimer’s Disease and Mild Cognitive Impairment,” Neurologic Clinics, no. 25 (2007). https://doi.org/10.1016/j.ncl.2007.03.008
[7] Stuart, Annie and Christopher Melinosky. “Brain Exercises and Dementia.” WebMD. 2020. https://www.webmd.com/alzheimers/guide/preventing-dementia-brain-exercises
[8] Graff-Radford, Jonathan. “Alzheimer's Disease: Can Exercise Prevent Memory Loss?” Mayo Clinic. 2021. https://www.mayoclinic.org/diseases-conditions/alzheimers-disease/expert-answers/alzheimers-disease/faq20057881#:~:text=Studies%20show%20that%20people%20who,modifiadddddble%20risk%20factors%20for%20dementia
[9] Mortimer, James A. and Yaakov Stern. “Physical exercise and activity may be important in reducing dementia risk at any age,” Neurology, no. 8 (February 2018). https://doi.org/10.1212/WNL.0000000000006935
[10] Blumenthal, James A., et al. “Lifestyle and Neurocognition in Older Adults with Cognitive Impairments: A Randomized Trial,” Neurology, no. 3 (January 2019). https://doi.org/10.1212/WNL.0000000000006784