In my opinion, the most important thing about people who are prone to cognitive impairment is that those who delve into their psychological state are the most at risk. Oh, why do I keep forgetting? I should ask Director Kim Si-ho about dementia. Let's go see the doctor. 

Hello, doctor. 

Hello. I tend to forget things a lot, and I have been a bit clumsy since I was young. My friends around me have said, You have a high chance of getting dementia later on. Is this true? 

The answer is no. 

Oh, it's not? You still have a long way to go before you reach the age where dementia could occur. There are many variables. We are on an aging curve that is like a speeding train. Dementia is also like a speeding train, and we need to see whether we are on a high-speed or low-speed train. If that is the case, then...

There are many variables and factors in between, so it's hard to make definitive statements. However, while I can't say for certain, it's possible that the speed might be slightly faster than average. Therefore, it might be good to put in a little effort. Doctor, you see many patients, right? Are there any characteristics that suggest certain individuals are more prone to dementia? Yes, there are. I have my own observations, as well as information from a Lancet committee report. First, let me mention what the Lancet committee discussed. According to the report released by the Lancet committee in 2024, around 5% of individuals did not receive early education during childhood. It’s important to note that this refers to the time before they started school, specifically during preschool years. There is a significant difference between those who were well cared for during that period and those who were neglected. The education received afterward is also important, and this accounts for about 5% of the influence.

In middle age, hearing loss contributes about 7% to the risk of dementia. High cholesterol, if left unmanaged, also accounts for around 7%. Lack of physical activity contributes about 3%, and depression is responsible for approximately 3% as well. Frequent head injuries contribute about 3%, while not engaging in physical activity again accounts for about 2%. Diabetes contributes 2%, smoking also contributes 2%, and hypertension accounts for 2% as well. Obesity contributes around 1%, and there are other factors that may account for about 1%. 

The most significant factor related to dementia is social isolation; when individuals do not have social contacts, it contributes about 5%. Pollution is estimated to contribute around 3%, and cognitive impairment contributes approximately 2% to the risk of developing dementia. People with these factors have about a 45% higher probability of developing dementia. This is an academic perspective, but in my view, the most critical factor for those at risk of dementia is age and being in a crowded environment.

Entering into the psychology of others is the most dangerous thing. At my age, it's true that many people have become as dull-witted as I am. Just because I’m managing doesn’t mean it’s okay. By the time I reach my average life expectancy, half of my life is already over. If my friends are similar, what does that mean for me? The likelihood of death is much higher. Even if I’m fortunate enough to be alive, what will I be like? I might end up with dementia. Therefore, I must never enter the mindset of my age group. When I compare myself to my high school and university classmates, I need to be significantly smarter to feel secure. This means I shouldn’t get caught up in the crowd mentality. There’s also a certain personality type, perhaps, that is prone to this. Yes, there is. To put it humorously, there’s the “lazy” type. They tend to avoid everything.

It's bothersome, and there is a person who has been starving. There are people who are somewhat detached, indifferent, and have a bad personality. There are people who are egotistical and lack empathy, only knowing themselves. These egotistical individuals can easily develop dementia. Changes in personality and behavior can lead towards dementia, and Alzheimer's disease can result in memory impairment. This often manifests as increased forgetfulness or a feeling that one's mind has deteriorated compared to before, which can be concerning to others as well. Therefore, it's beneficial to be diligent. While exercising a lot is important, it's also crucial to stay light on your feet and move around frequently. In a way, the world is fair. Teacher, these days, with smart devices...

We use it a lot, and as a result, life has become more convenient. At the same time, we don’t have to memorize things or use our brains as much. These phenomena are not good for dementia, of course. It is detrimental. Our brains like new, challenging things; we have a desire for knowledge. We express it like this: we have a constant desire to know more. However, if we keep satisfying that curiosity and discovering new things, our brains need to develop. If we become too comfortable, we stop using our brains. It’s like not exercising. Therefore, we can say that the decline in brain function is what we call digital dementia. As digital devices advance, that part of our brain weakens. It’s similar to how our legs weaken when we drive a car. So, our brains always need to overcome new challenges.

Using chopsticks with your left hand can be beneficial for your brain. So, teacher, if someone is often stressed or has some mental disorders, does that mean they are more likely to develop dementia? Oh, absolutely. Many people suddenly develop dementia after losing a spouse. For example, if someone is making my life difficult, how would I cope if my mind is in turmoil? It must be incredibly distressing. It’s better not to know. Similarly, stress can trigger dementia; there are mechanisms at play. Stress can lead to rapid deterioration of brain function, and stress is said to be the root of many diseases. When someone is stressed, their sympathetic nervous system kicks in, leading to excitement. Of course, this results in a lot of stress hormones being released, and substances that cause inflammation, like cytokines, increase, along with catecholamines.

Hormones are released in large amounts, which can excite the sympathetic nervous system. Another issue is that insulin resistance increases. When insulin resistance rises, blood sugar levels go up, leading to metabolic syndrome and laying the groundwork for various diseases. Additionally, when cytokines, which are inflammatory substances, are released, they can cause micro-inflammation, potentially leading my body into chronic inflammation, which is harmful. Catecholamines themselves constrict blood vessels, meaning that some areas receive adequate blood flow while others may not, resulting in possible circulatory issues. Furthermore, stress hinders intestinal movement. When the gut is compromised, it connects to the brain, causing mental decline to accelerate. For these reasons, high stress levels can lead to rapid cognitive decline, and insomnia can occur as a result.

There are talks that people who don't sleep well have a higher chance of developing dementia. Is this true? Sometimes, when we wake up, we might feel puffy, and at other times, we feel completely deflated. When we get enough sleep, our cells are active during the day, and there’s a lot of electrical activity happening, which can lead to excitement and anxiety. While we sleep, this electrical excitement is regulated, allowing our minds to calm down. If there is no inflammation in the brain, gaps can form between blood vessels. Through these gaps, cerebrospinal fluid can wash away waste like beta-amyloid toxins. This is one way it works. Secondly, during sleep, the electrical excitement gets organized, and when we wake up well-rested, our heads feel clear. However, if we don't sleep enough, our heads don't feel refreshed because the electrical excitement in the brain hasn't been properly reset.

If you keep pushing yourself in that state, it could lead to needing help and your mind deteriorating quickly. Do you have any recommendations for sleep duration? If you sleep too much, your mind can deteriorate, and if you don't sleep enough, it can also deteriorate. Sleeping too much means you're not using your brain, and if you're not using it, the unused part doesn't disappear and a lot of residue builds up, which keeps electrical stimulation lingering. That's why the mind can improve quickly. So, it's good to sleep at least 7 hours, but sleeping up to 10 hours might actually be harmful. 

Also, I'm curious because my maternal grandmother had dementia before she passed away, and I'm worried about genetics. Is dementia hereditary? Statistically, the hereditary aspect of dementia is about 1%, and around 20% is linked to the ApoE2 and ApoE4 genetic factors.

There is a genetic factor that slightly influences the onset of dementia after the age of 65. It is estimated that about 20% remains unidentified, but it may be affected by genetic influences. In total, about 40% of dementia cases may be influenced by genetics, although genetic diseases account for less than 1%. This information is primarily based on Alzheimer's dementia, and most vascular dementia cases are not hereditary. However, there are two types of hereditary vascular dementia: one that is inherited in a dominant manner, known as CADASIL, and another that is inherited in a recessive manner, known as CARASIL. It is said that there are some cases of CADASIL in Jeju Island. Nevertheless, most dementia cases occur regardless of genetic factors. To understand this more easily, we can compare it to tires: we are born with A-grade tires, while there are B, C, D, E, and F grades. F is not a defective product; rather, it is a retreaded tire.

Good tires are really great when they are born, and if they only run on well-paved roads, they can wear out quickly. If you don't have good habits, no matter how genetically gifted you are, dementia can come on quickly. Even when driving on regenerated tires, if you drive calmly on asphalt roads, there is a warranty period of 5 kilometers, but you can drive 7 or even 88 kilometers. It's the same with our brains. In some ways, environmental factors have a much greater impact than innate ones. When I was young, teachers would sometimes hit students on the head, and rebellious kids would say, Teacher, you might give me dementia later. Is that true? While we can't take pictures or extract data from tests to prove it, it's clear that if such things accumulate, it can definitely lead to cognitive decline. The first hit from a teacher is, in itself, a shock to the brain.

Only stress is a problem, so it must be worse. Aside from that, when boxers frequently take hits to the head, which is not a stress factor but rather a physical one, it can lead to brain damage. This can also happen in war zones, and due to this, the likelihood of developing dementia increases by about 3%. If a factory is running and a lightning strike hits it, or if a typhoon blows through and it gets damaged, or if an earthquake occurs, what happens? The factory would be completely destroyed. Similarly, consuming alcohol, smoking, or using harmful substances like drugs can also damage the brain. As mentioned earlier, when athletes are repeatedly hit or when someone is involved in a traffic accident or falls and injures their head, this results in physical brain damage. Therefore, it leads to brain injury.

Physical brain damage is like our house being bombed. We need to be careful about such things. When you drink a lot, it's often said that you black out, and if this happens repeatedly, it can lead to dementia. In fact, when food is soaked in salt, it becomes weaker, and the same can happen with alcohol. Our brain is a very delicate tissue, and while alcohol may only be present in small amounts, if it gets soaked in it, it can weaken. If the concentration is high enough to cause a blackout, it's obvious that it can harm the brain. Repeated anesthesia can also be detrimental. A few times might be okay, but excessive use is not good. 

Then, doctor, there are people who habitually use propofol, which has been a recent issue. That should not be done, right? Of course, it will make things worse for me.

Drugs, alcohol, and anesthesia are bad things, and it’s best to stay away from them as much as possible. Although there are times when one cannot avoid them, repeatedly using them can lead to issues. Oh, I see. I guess I should have my eye exam done without sedation. Even without sedation, it’s not that difficult. Oh really? It can be tough, though. Doctor, I’ve been looking into various ways to actively prevent dementia, and I’d like to ask for one last piece of advice. It’s important to detect dementia early, but it’s even more crucial to identify it beforehand. This is because, by the time dementia is diagnosed, many dead cells and zombie cells have already formed. The further you are from the onset of dementia, the fewer dead and zombie cells there are. There are more cells that can still be treated the further you are from the onset of dementia. Therefore, it’s better to detect it early, and treatments can include dietary therapies and traditional herbal medicine, which can also be helpful.

Today, I heard a lot of stories, and in a way, many of them seemed to apply to me. There is a law of the total amount of joy. If you spend too much joy when you are young, you won't have any left for later years. Of course, you shouldn't live without joy at all. However, if you live while being considerate and saving a bit, you can enjoy a lot of joy in your later years. Joy also follows the law of total amount. I feel like I spent quite a bit early on, but that's life. Thank you. Thank you.

🚨치매는 이런 사람이 잘 걸린다! 혹시 나도 이런 유형에 속하지 않는지 꼭 확인해 보세요!🚨[의사결정 ep.51 Full Ver.]

정보가 넘쳐서 헷갈릴 땐 실용적인 정보만, 실컷 묻고 따져봄! 🤗 ('실컷'은 CBS 노컷뉴스가 운영하는 노컷비즈 영상채널입니다)