Why do older people start to develop Alzheimer's and how can we slow down its progression?

In this research project, I am trying to figure out why older people get Alzheimer's? I also want to learn different ways to slow it down, since we can't prevent it.
Sarah Lu
Grade 6

Problem

When we get older, we start to forget things. That is a common type of dementia called Alzheimer's. It can start off easy like forgetting where you put your car keys or forgetting what you had for breakfast the day a couple of days ago. But it will get worse. You can start forgetting what you just ate for dinner or what kind of conversation you just had. Once you get severe Alzheimer's, you'll start to forget who your friends or family are, or even not being able to move, think, or talk properly. People who have Alzheimer's depend on others. Unfortunately, you cannot stop it, however, you can delay it.

The purpose of this project is to figure out why people start to develop Alzheimer's. I also want to find out how we can slow down its progression since scientists haven't figured out a cure for how to completely stop it.

Method

Method 1

1. Research what Alzheimer's is

2. Research how we can prevent/delay it

3. Research why older people develop Alzheimer's

4. Add data and innovation(s)

 

Method 2

Research highlight: Plaques, tangles, and the microglia are the main reasons for Alzheimer's. They either make the neurons not able to send signals to each other or eats the neurons. There are some ways to delay Alzheimer's: exercising, eating healthy, socializing, doing puzzles, and avoiding smoking. Although there are no cures for Alzheimer's, a medicine has been created called Leqembi. It kills the plaques, slowing the progression of Alzheimer's down.

Innovation

  1. Much like we enhance a human’s heart with a pacemaker to help it operate better, we could invent a similar device for our brain to tackle Alzheimer's. This device can make the brain sharper (more awake) and make it less prone to mistakes (beta amyloids).
  2. Imagine in the future, scientists successfully developed a medicine designed to prevent Alzheimer’s. We can then package it as a daily supplement similar to multi-vitamin that we can take in an early age, so that we can delay the development of Alzheimer’s as we grow older.
  3. We all know that there is a medicine to slow down the progression of Alzheimer’s by 7.5 months if you take it for 18 months. If the Alzheimer’s patient keeps taking Leqembi for a longer period, the progression can be slowed down even longer. However, can the patient’s family see/feel and differences about the Alzheimer’s patient? Even though the Alzheimer’s progression was slowed down, the stages of it will still eventually happen. So shouldn’t we focus on the early detection and treatment before the Alzheimer’s symptoms occur, rather than attempting to completely eliminate the cause? This approach could lessen both the burden of the Alzheimer’s patient’s body/brain and the patient’s family. As we know, the microglia can eat unhealthy cells, including beta amyloids, but then the microglia can start eating completely fine neurons because the individual is either unhealthy, has sleeping problems, or stressed. So if we keep eating healthy products like vegetables and fruits, the microglia can keep on eating the beta amyloids, preventing it from releasing toxic chemicals and blocking the signals of the neurons.
  4. When someone has blood cancer, another person with healthy blood can donate their blood to the person who has blood cancer. So why not do that with a person with Alzheimer’s? As said earlier, one reason for why older people develop Alzheimer’s is because their body cells die as they get older. So what if some people willingly donate their healthy body cells for the person with Alzheimer’s? That way, the person with Alzheimer’s can have the dementia slowed down. 

Research

What is Alzheimer's and dementia? 

Dementia is a general term for forgetfulness, having difficulties to think properly, or interference in doing normal daily life work. It is like a mall. Dementia is the huge building and inside it are the different shops. The shops are for different types of dementia, including Alzheimer’s. 

Alzheimer’s is a type of dementia, most known as Alzheimer Disease. It’s a neurodegenerative disease. Neurodegeneration is when the neurons in the brain stop working or die, degenerating. The brain shrinks slowly and slowly, causing memory loss. Symptoms usually start at the age of 65, but Alzheimer’s actually starts at 55.

Alzheimer’s was first discovered in 1901, by Dr. Alois Alzheimer. He had a patient who had short term memory loss and was acting abnormal. When the patient passed away, Dr. Alzheimer did an autopsy on the patient’s brain. While he was examining the brain, he noticed that the brain had shrunken and had some things blocking the neurons.

 

Alzheimer’s is caused by plaques, tangles, and the microglia

Plaques are beta amyloids that build up and block the signals of the neurons. Neurons send signals throughout your brain that tell you to talk, think, and move. Once the plaques block the signals, your brain cannot function properly. When it can’t function properly, your body and brain cannot do what a normal person can do. Once the neurons can’t send signals, the brain shrinks, causing Alzheimer’s. Beta amyloids can seriously get in the way of the neurons, which can cause inflammation. The inflammations can damage the neurons, which will also disturb the signaling. 

How are even beta Amyloids made? - Originally, beta Amyloids were once helpful to the brain. It helps other cells attach to each other. They were called Amyloid Precursor Protein, or known as APP. The APPs, a protein, are in between a cell membrane in a neuron. One end of the APP is outside of the neuron, while the other end is inside. Scientists say that the APP helps the neurons repair itself when it is damaged. Like anything else, it eventually gets broken and the brain doesn’t need it anymore. So when the brain doesn’t need that APP anymore, it cuts it off into two parts.

An enzyme (an enzyme is a special protein that speeds up the process of the metabolism or a chemical reaction happening in the human body), an alpha secretase and gamma secretase cuts the protein. The alpha secretase cuts off the upper part of the APP and the gamma secretase cuts off the middle/end of the APP. When it is done correctly, the APP should dispose properly and cause no problems. In the incorrect way, another enzyme, beta secretase, cuts off the very tip of the APP. Then the gamma secretase cuts off the bottom. While the tip is disposed of, the bottom stays and doesn’t go away. Now, it is called the beta Amyloid. The beta amyloid also sticks to the neurons and releases toxic chemicals, causing the neurons to die.

Picture of how the APP is cut (sissors are the enzymes.)

 

Tangles are caused by loose tau. Tau is a special protein that keeps the neurons together, so that they don’t come apart. Although scientists and doctors haven’t figured out the exact reason, they have done a lot of research and have found some theories on why it happens. Tau comes apart by the toxic chemicals of the beta amyloids. Since tau is sticky, they stick together, creating more clumps in the brain. Those clumps are called tangles. The tangles block the signals from the neurons as well. Since the tau has fallen off, the neurons are falling apart. Once the neurons start to die or fall apart, many changes happen to the brain and body, such as brain shrinkage and memory loss.

The microglia also contributes to Alzheimer’s. Just like tau (tangles) and beta Amyloids (plaques), they have once helped the brain in a good way. But once the person has grown older, the microglia has turned its back on the person. When the person gets into their forties-sixties, the microglia can kill the brain cells/neurons and cause inflammation. When the person is younger, the microglia actually helps the brain. If the brain has a little damage to it, the microglia can help heal it. But just like the beta Amyloids and tau, it eventually turns bad, and we can’t do anything about it. 

The microglia is something very helpful to the brain. It does many things to help. First, it clears bad things out of your brain. Microglias search for dead brain cells/neurons, harmful protein clusters, and pathogens. Pathogens are something that starts a disease in the brain. It searches for dead/damaged neurons or diseases and when it finds it, they grab it with its spidery arms. Then it turns itself into a blob and eats the problem. They also touch neurons to see if it is okay or not. If the neuron is not okay or releasing some type of chemicals, it will eat it. Although it might sound a bit violent, it’s actually very helpful. But then how is it a cause for Alzheimer’s? Well, if you are stressed, having sleeping problems, or your diet is unwell, the microglia can eat the healthy neurons, causing Alzheimer’s. Scientists say that microglias can be helpful to prevent Alzheimer’s but can also cause it. Microglias can eat the plaques and tangles, but it can also go too far and eat the healthy neurons as well, resulting in helping increase Alzheimer’s.

 

Stages of Alzheimer's

 

Stage 1 is when the individual starts to develop short term memory loss. During this stage, the individual may forget information shortly after being told.

Stage 2 is when the individual cannot process logical thoughts. For instance, the individual may find it challenging to follow a cooking recipe to prepare a simple meal, or the sequence of steps to assemble an IKEA furniture.

Stage 3 is when Alzheimer’s disease progresses to impact areas of the brain that regulates our emotions. As a result, the individual may experience sudden mood changes. For instance, when the individual who has Alzheimer’s is happy, the next second you turn back to that person, they can have a totally different emotion.

Stage 4 is when the individual not only have challenge remembering things but may also start to experience hallucinations, such as seeing or hearing things that aren’t really there. For instance, the individual might think that there’s someone in the room when there isn’t.

Stage 5 is when the individual forgets their long-term memories, including relationships with their family and friends.

Stage 6 is when many essential parts of the brain aren’t working as they should, making it very challenging for the individual to manage daily tasks independently.

Stage 7 is normally considered as the final stage, where the individual has significant decline with their mental abilities, loss of communications skills and is completely depended on others to help with their daily activities. At this stage, the individual might lose their ability for basic movements, or even swallow.

 

Ways to delay Alzheimer’s

  1. Exercising - Exercising is known for keeping your body healthy, but can it help delay Alzheimer’s? The answer is, yes, but how? Well, there are certain exercises that can delay Alzheimer’s. Aerobics is a type of exercise that uses a lot of oxygen and pumps more blood than weight lifting. Blood is very important for delaying Alzheimer’s. Blood is important because when people start to develop Alzheimer’s, less blood gets to the brain. Here are some examples of aerobics: running/jogging, bicycling, swimming, dancing, and hiking. What makes aerobics different from other workouts is that it lasts at least 45 minutes to an hour for moderate aerobics, and 30 minutes to 45 minutes for vigorous aerobics per session 5 days a week.Weight lifting can last up to 60-90 minutes if you are only doing it for one day a week. If you train 2-3 days a week, then it would last for 40-60 minutes per session. Exercising also makes your body energized. When it is energized, your body is more energized and can heal broken cells easier. 
     
  2. Socializing - Socialization is a great mental workout for the brain. It exercises the brain and makes it energetic, hence making it less prone to making mistakes (cutting the wrong part of the APP, making it beta amyloid). 
     
  3. Eating healthy - Eating healthy can help prevent inflammation in the brain, protecting it from damaging the neurons. It can also make it easier to defecate, taking more bad things out of the body. 

    Here are the types of foods to delay Alzheimer’s: Fish, omega 3, fruits, vegetables, and nuts. 
    • Omega 3 - Omega 3 is known for improving memory, and that is true. It also reduces the risk of inflammation in the brain. 
    • Fish - Fish contains omega 3, which is helpful in delaying Alzheimer’s.
    • Fruits and vegetables - Fruits and vegetables contain something called flavonoids. Flavonoids have anti-inflammatory properties. It can soothe inflammation that is happening in the brain. Also, it improves the blood flow which helps the brain function.
    • Nuts - Nuts have omega 3 inside it, which is helpful for delaying Alzheimer’s.
       
  4. Puzzles/Reading - Doing puzzles can improve your brain functions. It challenges your brain to work. When doing jigsaw puzzles, the person uses their long-term memory to figure out which puzzle piece goes where by color, shape, and patterns. Although this may seem like a simple activity for a person younger than 40-30, a person with Alzheimer’s is harder because they can get frustrated easily. As said earlier, stage 3 is when the person has sudden mood changes. Even though they might be excited to start a new jigsaw puzzle, two minutes later, they might be angry or upset. It is also harder for them because they might not remember the rules and patterns of a jigsaw puzzle. Sudoku and crossword puzzles also might be able to slow the progression of Alzheimer’s. Studies say that it doesn’t make a huge impact, but it is still better than nothing. 
     
  5. Avoid smoking - We all know that lung cancer is mostly caused by smoking, but it is a cause for Alzheimer’s as well. It damages the blood cells in the body, making it hard to send blood to the brain. The brain needs blood to function, and if blood is not going to it, it will fail to function. Another reason is that smoking causes inflammation. Inflammation is when the body swells. But if that happens in the brain, it can damage the surrounding brain cells.  

 

Medicine for Alzheimer’s

Although there is no cure for Alzheimer’s, there is a medicine to slow down Alzheimer’s, and that is called Leqembi (Le-kem-bee). Leqembi removes the beta amyloids/plaques out of your brain. It is designed to dissolve the beta amyloids and eliminate them through urination or defecation. Every 2 weeks for one hour, Leqembi is inserted into your body by an IV. The data has shown that on average, a person taking Leqembi for 18 months delayed Alzheimer’s by around 7.5 months. A regular person who had Alzheimer’s and didn’t use Leqembi didn’t show any signs of lowered Alzheimer’s progression. (see graph in Data section reference.) However, it is only effective in early stages.

Leqembi is made by two companies named Eisai and Biogen. It is a collaboration between America (Biogen) and Japan (Eisai). Unfortunately, it is only been approved in America, Japan and China at the time of these research, and not yet approved in Canada. There are others downsides to this medicine besides its price. Leqembi can cause headaches, dizziness/nausea, brain bleeds, swelling, and vomiting. But I would definitely take it.

Eisai is creating an Alzheimer's test similar to a Covid test. You would take a little bit of your blood and check if you have Alzheimer’s or not. The company says that it is expected to release in 2030 and make it available to purchase at your local drugstore. You can take the test when you are 50 to see if you are starting to develop Alzheimer’s and start treatment if the test result is positive.

 

Now, for the final grand question, why does Alzheimer’s start to happen when you get old?

Exercise improves our energy levels and helps the quicker healing of damaged cells. As we age, particularly between 55 and 65, there is a tendency to become less active. 65 is the age when many people begin their retirement. During our working years, we use both our bodies and minds more actively; however, upon retirement, there is a higher chance of spending more time at home and become less active.

Until the age of 16(girls)/18(boys), their bodies develop. Then for the rest of their lives, they use the cells their body created for them. And then, when they are in their late fifties/sixties, the cells get tired and start becoming slower and slower, eventually dying.

Data

Here are the dementia percentages in Alberta and Canada from 2002 to 2021 (Source: https://health-infobase.canada.ca/ccdss/data-tool/. Note - the data shows dementia rates because there was no available data on the internet that showed only Alzheimer's.)

Dementia (incl. Alzheimer's) Population % for Age 65+ both female and male

Here is a table for data from Alberta and Canada:

Fiscal year Per 100K
(Canada)
Per 100K
 (AB)
Percentage
 (Canada)
Percentage
 (AB)
Population 65+
 (Canada)
Population 65+
(AB)
Est. Count
(Canada)
Est. Count
 (AB)
2002–2003                 1,573                 1,987 1.57% 1.99%                4,042,945                  323,710           63,596               6,432
2003–2004                 1,563                 1,934 1.56% 1.93%                4,110,195                  330,230           64,242               6,387
2004–2005                 1,554                 1,839 1.55% 1.84%                4,176,765                  336,765           64,907               6,193
2005–2006                 1,509                 1,792 1.51% 1.79%                4,257,870                  345,905           64,251               6,199
2006–2007                 1,537                 1,727 1.54% 1.73%                4,349,450                  356,380           66,851               6,155
2007–2008                 1,529                 1,771 1.53% 1.77%                4,453,765                  366,695           68,098               6,494
2008–2009                 1,576                 1,746 1.58% 1.75%                4,624,920                  378,815           72,889               6,614
2009–2010                 1,577                 1,729 1.58% 1.73%                4,750,250                  390,635           74,911               6,754
2010–2011                 1,555                 1,678 1.56% 1.68%                4,890,215                  403,820           76,043               6,776
2011–2012                 1,545                 1,739 1.55% 1.74%                5,091,980                  423,630           78,671               7,367
2012–2013                 1,507                 1,689 1.51% 1.69%                5,305,355                  446,435           79,952               7,540
2013–2014                 1,472                 1,582 1.47% 1.58%                5,511,085                  468,460           81,123               7,411
2014–2015                 1,482                 1,581 1.48% 1.58%                5,697,245                  491,480           84,433               7,770
2015–2016                 1,463                 1,637 1.46% 1.64%                5,893,955                  514,520           86,229               8,423
2016–2017                 1,440                 1,607 1.44% 1.61%                6,114,035                  539,455           88,042               8,669
2017–2018                 1,419                 1,588 1.42% 1.59%                6,344,455                  567,945           90,028               9,019
2018–2019                 1,419                 1,554 1.42% 1.55%                6,590,825                  599,830           93,524               9,321
2019–2020                 1,407                 1,508 1.41% 1.51%                6,858,190                  634,970           96,495               9,575
2020–2021*                 1,300                 1,288 1.30% 1.29%                7,083,545                  668,775           92,086               8,614
Source: https://health-infobase.canada.ca/ccdss/data-tool/

Here is a chart for people who used Leqembi and people who didn't:

The green shows the people who took Leqembi. The black shows the people who took a placebo. A placebo is like a fake medicine that makes you feel better but doesn't cure anything. On the left side that shows 0, 0.4, 0.8, 1.2, and 1.6 are how bad the Alzheimer's rates had gotten. The numbers on the bottom on the graph that says 0, 4, 6, 9, 12, 15, and 18 are the months that went by. Although the patients who took Leqembi wasn't completely cured, it slowed down the progression of Alzheimer's.

 

This graph shows how Alzheimer's progresses. After that dotted line, it is when symptoms of Alzheimer's starts to show.

Conclusion

The reason for Alzheimer’s is because of plaques and tangles. It is also caused by the microglia. Plaques are caused by cutting off the wrong part of the APP. Tau and plaques block the signals of neurons.

The microglia were once helpful to the brain, but when the individual starts getting unhealthy, the microglia start eating the healthy neurons.

Some ways to delay Alzheimer’s (without medication) are: exercising, puzzles, eating healthy, socializing, and not smoking. While exercising, your body makes more blood, which is helpful to the brain. Puzzles use your short-term memory and long-term memory. Socializing is a great mental workout for your brain. Eating healthy prevents inflammation and improves memory. Smoking can cause inflammation so it is a good idea to not smoke.

Leqembi is not a cure for Alzheimer’s but it removes/kills beta amyloids. It is inserted by an IV and can be extremely helpful. Data shows that people who took Leqembi for 18 months had their Alzheimer’s slowed down by 7.5 months. I hope that it can soon be approved in Canada so that Canadians who have Alzheimer's can benefit from it.

Citations

https://www.cdc.gov/aging/publications/features/reducing-risk-of-alzheimers-disease/index.htm -Dec 15, Friday 2023

https://www.alz.org/alzheimers-dementia/what-is-alzheimers -Oct 19, 2023

https://www.nia.nih.gov/health/alzheimers-disease-fact-sheet#:~:text=The%20causes%20probably%20include%20a,differ%20from%20person%20to%20person -Oct 19, 2023

https://www.terravista.org/8-ways-to-slow-the-progression-of-alzheimers-disease/ -Dec 23, 2023

https://www.pbs.org/wgbh/nova/article/alzheimers-dementia-exercise-sleep/ -Dec  23, 2023

https://www.michiganmedicine.org/health-lab/what-you-can-do-now-prevent-alzheimers-disease -Dec 23, 2023

https://www.alzheimers.gov/alzheimers-dementias/alzheimers-disease#what-causes-alzheimer%E2%80%99s -Dec 27, 2023

https://www.nia.nih.gov/health/genetics-and-family-history/alzheimers-disease-genetics-fact-sheet#:~:text=In%20most%20cases%2C%20Alzheimer's%20does,reduce%20the%20risk%20of%20Alzheimer's -Dec 27, 2023

https://www.brightfocus.org/alzheimers/article/smoking-good-or-bad-dementia-prevention -Dec 27, 2023

https://www.nia.nih.gov/health/alzheimers-and-dementia/alzheimers-disease-fact-sheet#:~:text=Ultimately%2C%20plaques%20and%20tangles%20spread,as%20the%20body%20shuts%20down. -Jan 5, 2024

https://www.youtube.com/watch?v=5dmqaH-MlA0&ab_channel=PeekabooKidz -Jan 5, 2024

https://www.statista.com/statistics/1345588/canada-number-with-dementia-province/ -Jan 26, 2023

https://www.youtube.com/watch?v=v5gdH_Hydes&ab_channel=OsmosisfromElsevier -Feb 8, 2024

https://www.youtube.com/watch?v=yJXTXN4xrI8&ab_channel=TED-Ed -Feb 8, 2024

https://www.youtube.com/watch?v=0GXv3mHs9AU&ab_channel=NationalInstituteonAging -Feb 8, 2024

Scientific American (Book) - February 13, 2024

https://alzheimer.ca/en -Feb 15, 2024

https://www.alz.org/ -Feb 15, 2024

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9588915/ -Feb 15, 2024

https://www.nhs.uk/conditions/alzheimers-disease/prevention/#:~:text=exercising%20for%20at%20least%20150,diet%20and%20take%20your%20medicine -Feb 20, 2024

https://www.livestrong.com/article/13767612-how-long-should-a-weight-lifting-workout-last/ -Feb 23, 2024

https://www.washingtonpost.com/wellness/2023/09/18/diet-brain-health-preventing-alzheimers/ -Feb 24, 2024

https://www.restinpieces.co.uk/blogs/news/are-jigsaw-puzzles-good-for-dementia-patients -Feb 24, 2024

https://www.everydayhealth.com/senior-health/alzheimers-disease/12-fun-brain-games-adults/ -Feb 25, 2024

https://www.alzheimers.org.uk/about-dementia/managing-the-risk-of-dementia/reduce-your-risk-of-dementia/smoking#:~:text=There%20is%20strong%20evidence%20to,Alzheimer's%20disease%20and%20vascular%20dementia. -Feb 26, 2024

https://www.brightfocus.org/alzheimers/article/smoking-good-or-bad-dementia-prevention -Feb 26, 2024

https://www.health.harvard.edu/blog/what-to-eat-to-reduce-your-risk-of-alzheimers-disease-2020050819774 -Feb 27, 2024

https://primehealthdenver.com/alzheimers-diet/ -Feb 27, 2024

https://www.everydayhealth.com/diet-nutrition/what-are-the-benefits-of-fish-oil-for-memory/ -Feb 27, 2024

https://www.health.harvard.edu/mind-and-mood/the-thinking-on-flavonoids -Feb 27, 2024

https://www.alz.org/alzheimers-dementia/treatments/lecanemab-leqembi -Feb 29, 2024

https://www.uchealth.org/today/how-well-does-leqembi-fight-alzheimers-first-fda-approved-alzheimers-drug/ -Feb 29, 2024

https://www.ncoa.org/article/leqembi-and-alzheimers-disease-the-benefits-side-effects-and-what-it-costs -Feb 29, 2024

https://www.statcan.gc.ca/o1/en/plus/5374-alzheimers-awareness-month -March 1, 2024

https://www.youtube.com/watch?v=3AqKU5ktBG4&ab_channel=SciShowPsych -March 3, 2024

https://www.eisai.com/news/2023/news202374.html -March 5, 2024

https://investors.biogen.com/news-releases/news-release-details/leqembir-intravenous-infusion-lecanemab-treatment-alzheimers -March 5, 2024

https://www.nature.com/articles/s41380-021-01249-0 -March 13, 2024

https://pubmed.ncbi.nlm.nih.gov/23847585/ -March 13, 2024

https://pubmed.ncbi.nlm.nih.gov/20826658/ -March 13, 2024

https://pubmed.ncbi.nlm.nih.gov/24493463/ -March 13, 2024

https://kids.frontiersin.org/articles/10.3389/frym.2021.578214#:~:text=There%20is%20a%20direct%20relationship,synaptic%20plasticity%20of%20the%20brain. -March 14, 2024

Acknowledgement

I would like to thank my science fair instructor Ms. Blyth and Mr. Chong. Ms. Blyth allowed me to have the opportunity to join the science fair. Ms. Blyth has answered my questions about the science fair + my project, as well as Mr. Chong.

I will also like to thank my mom for helping me for buying the Alzheimer's book so that I can extend my research. She has also pushed me and encouraged me to keep on going. Also, she has also bought an extension for my tri-fold so that I could add more picutres to it.

My family was a great help to my project (my sister, dad, and mom). I presented in front of them multiple times and they added suggestions to them.

And finally, I want to thank my dad for helping me create these amazing graphs and tables for my project. He printed all the papers I needed. Also, he bought my tri-fold for me.