Alzheimer's Disease
What is "Alzheimer's disease"?
Alzheimer's disease happens to be the most common type of dementia. Dementia basically means a syndromal state in which people have a problem with their short term memory. Associated with that, alzheimer's disease sufferers typically also have some problems with neurological processing. For example, finding the right word to use in conversations, maybe having problems with their ability to do things with their hands, maybe getting lost, or lacking the ability to plan or organize things. Typically when the individual develops a dementia, there's going to be problems with their ability to do their job or to socialize the way that they did before, and these things can readily be noticed by other people. We have ways of diagnosing Alzheimer's disease, which like I said, happens to be the most common dementia that we encounter out there.
What are the symptoms of Alzheimer's disease?
The most common symptom of Alzheimer's disease happens to be short-term memory loss. So in other words, people retain their ability to remember things long-term; where they went to school or elementary school, what their hometown was, and so on. But they can't really remember what transpired, say, a week ago or otherwise. And typically, it's going to be a little bit of a memory complaint early on. Remember, Alzheimer's goes through different stages, and depending on the stage in which the individual resides, there's going to be added problems. Typically, people can't do the things that they did before, so their ability to do things functionally will drop off. In addition, behavioral problems also initiate as the illness gets worse.
What are the stages of Alzheimer's disease?
Alzheimer's goes through three diffferent main stages, mild, moderate, and severe. Most people, unfortunately, aren't caught in the milder stage. The mild stage of Alzheimer's typically lasts maybe two to four years. The moderate stage is the one that lasts a little longer and the one that most people oftentimes get identified is in the clinical setting, and that can be as long as ten years, even. The severe stage typically also lasts a brief period of time, two to four years at the top. But, in essense, the individual that's now reached that greater severity staging of Alzheimer's now requires somebody else to procure for their basic needs. In other words, they rely on someone else to get dressed, eat, and care for themselves.
What happens to the brain of an Alzheimer's patient?
The brain literally starts to atrophy, or shrink. We basically see that the space in between these noodle-like formations that the brain is made of start to get wider. The brain matter itself starts to thin out. The ventricles look larger, and literally as this illness is getting worse, there's a gradual atrophy or loss of volume that the brain takes on.
What are "plaques" and "tangles"?
Plaques and tangles are features that are characteristics of Alzheimer's disease. Let's break this down. Plaques are accumulations of a compound or material called amyloid. And the specific type of amyloid that we find is beta-amyloid outside of cells. Literally, an insoluble type of amyloid that cannot be carried out of the brain that literally chokes off brain cells. That is not, however, the only problem that exists with Alzheimer. So the tangles are found inside of the cells themselves. The plaques are outside of the cells. The problem within the cells is that there's been a hyperphosphorylation - a fancy word of saying that the structures that hold up that cell cave in and cause it to die.
What do plaques and tangles do?
As a result of the plaques and tangles, there's literally a choking off process that occurs with the tissue of the brain. If it's being choked off, you don't have the same type of circulation or, again, the opportunity for growth and maintenance in that brain tissue. As a consequence of that, there's a dying off of different areas of the brain. Problem starts out in the basal forebrain, deep in the temporal region, spreads over to the bi-temporal parietal areas and then all of a sudden spreads over to the frontal lobe.
How did plaques and tangles play a role in the history of Alzheimer's?
Plaques and tangles were first described by a Bavarian psychiatrist by the name of Alois Alzheimer. That's how this illness derived its name, and, by the way, it was someone else that dubbed it Alzheimer's disease. So, Alois wasn't necessarily an egotist who named the illness after himself. He was the first individual that described this condition literally 100 years ago. So, back in 1907, a gentleman basically came in seeking Alois' help and basically stated that his wife, a woman by the name of Auguste D, who had started out with some memory problems, and again, this was a woman who was in her early fifties, had also developed some very strange and unusual symptoms. She had become psychotic and was having a lot of behavioural problems. Upon death, what Alois decided to do was to scoop out some brain tissue and take a look at it under a microscope. He found what are still considered the pathognomonic, or the telltale signs associated with the illness. The plaques, which he called senile plaques, are basically extra-cellular Beta-amyloid plaques and tangled neurons. In other words, this is a situation in which hyperphosphorylation of the tau protein with thin cells creates a problem, whereby the cytoskeleton of the neuron or the brain cell, all of a sudden, causes a collapse within itself. So, again plaques and tangles are the telltale signs that we need to verify that, in fact, this individual suffered from Alzheimer's disease. The reason that they are important is that this is the only way to make a 100% accurate diagnosis of the illness. One thing that is important, though, is that just based on the clinical acumen, or in other words, the notion that we have made sure that all other causes have been ruled out, the doctor can make a diagnostic certainty of this illness with a degree of about, maybe 90-95% accuracy.
What does an Alzheimer's patient remember most?
Alzheimer's patients oftentimes have a problem with their memory processing. So in other words, it is like having a tape recorder that plays but can not really record anymore. And the unfortunate situation is that we lose neuronal circuitry in this disease state. There are associated features in Alzheimer's disease that are theorized to be at the center of the problems associated with Alzheimer's. Extra cellular neurodic plaques would be to hamaloid cords and intra-cellular neuro fibulary tangles. Fancy words for saying that there is a cluttering process that is going on in the brain that is now creating a loss of the volume of brain tissue. If we start to lose brain tissue, unfortunately now we lose neuronal networks, or circuits that were previously were working well. And as a consequence of that, it makes sense why people can not retrieve recent memory. And where memory resides is really a great question of the present time. In essence, we think short term memory ties into the hippocampal region. Another words, a deep area in the basal forebrain right next to the temporal lobe. However, we know that that is one area that is being affected strongly by Alzheimer's disease. And in essence, it helps explain why it is that people have problems with short term memory recall. But not necessarily long term recall in the disease state. Later on it is a different story because unfortunately, as this disease gets worse, different areas of the brain are being affected.
Where does Alzheimer's disease begin to affect the brain?
The problem begins, as I said, in the basal forebrain. In other words a deep limbic region residing deep in the temporal lobe. In essence what we know about this illness is that both sides of the brain get affected, so there's a bitemporoparietal decrease in, again, the loss of function and volume, which then subsequently migrates over to the frontal portion of the brain, frontal cortices.
Where does the memory reside that is damaged by Alzheimer's disease?
Where does memory lie in the brain? That's a terrific question. We think it resides all over the place. However, short-term memory appears to be associated with specific areas, like the hippocampus, which is an area deep in the temporal lobe. Some of the associated areas that are affected early on by Alzheimer's disease include the nucleus basalus of Meynert which is, again, in that same basal forebrain region. So, specifically, short-term recall, we think, is associated with the hippocampal structure, here.
What effects does Alzheimer's have on the body?
Alzheimer's oftentimes debilitates the individual. Remember, the reason by which people die with this illness is that their bodies can become so frail that they now open up towards a situation, would say a pneumonia to set it and cause the demise of the individual. Literally the individual with Alzheimer's disease has a greater likelihood of suffering from additional medical problems, probably because they're not addressing those medical problems in the appropriate fashion because they become "forgetful" and don't follow through with treatment regimen recommendations the way that they should.
What are the risk factors for Alzheimer's disease?
Risk factors for Alzheimer's disease happen to include older age, so again, people over the age of 65 are at much greater risk. Things like diet are also important. A high cholesterol diet might not be such a good thing. Activity levels, again, staying active would be good. What a surprise that is right? Eat right and exercise and you'll live longer. Well the same thing stands by this illness. Other things that might have an impact include things like having suffered a blow to the head earlier on in life. Traumatic brain injury often can create somewhat of an issue. Vascular risk factors like diabetes or hypertension that haven't been well controlled can unfortunately contribute to additional insults that somebody with Alzheimer's disease would make their illness look worse. But the biggest things, would be advancing age and a family history of the illness.
What are some of the early warning signs of Alzheimer's disease?
Common telltale signs in the early stage of Alzheimer's disease can include things like repeating oneself, being more forgetful, maybe losing oneself in a place that previously would have been very familiar to the individual, asking the same question, and again maybe being aware that there's a little bit of a drop-off in the ability to remember things. Another tell-tale sign of Alzheimer's disease is maybe dropping out of some of the usual activities that the individual engaged in. For example, the person that previously was an avid golfer is now reticent to do so because maybe his buddies will notice that he's not keeping score right and so on. Oftentimes there's a little bit of a social withdrawal that sets in. Sometimes Alzheimer's can be confused with depression early on, because individuals that share features with depression become inattentive, can't concentrate, can't focus, and are less motivated as a consequence of that. Sometimes there's a question “could this be depression?” or “could it be anxiety?” because the individual that's anxious also can't focus and attend to things, and as a consequence of that wouldn't be able to remember with as solid detail as the individual that would be paying close attention to what's going on around them. The early stage, literally, typically involves memory processing. That's why, unfortunately, many people fall through the cracks or fall through the sieves of not being identified. Remember, one of the more common reasons for an acute confusional state in somebody that's older could actually be tied into an interaction with their medications. If they're taking a combination of medications that isn't good, or they have a disease state (let's say their liver or their kidneys aren't working well in conjunction with the new medicine) that could actually bring about confusion. That might mimic, look like, a dementing process. That's why it's so important to get a detailed, clinical workup whenever there's a question as to whether this could be Alzheimer's disease or not.
What are the dangers of late-stage Alzheimer's?
In the late stage of Alzheimer's disease, unfortunately that person has probably now had a severe problem with their memory. They might forget or not recognise who a family member is or might not even recognise themselves when they look in their mirror. As a consequence of that, they become belligerent or maybe combative and agitated, and may even have some striking out behaviour. That same individual might now be wetting the bed or become, aside from being incontinent of say, just urine, might also become incontinent of faeces as well. By the way, combativeness and incontinence are the main reasons for which people oftentimes end up in a long-term care setting. So, in other words, a skilled nursing facility oftentimes is a requisite for somebody that is now having some of these really bad behaviours that most caregivers would not be able to help out with. Now, remember, prior to this point, the caregiver might have become involved in a minute way. In the early stages of Alzheimer's disease, a caregiver might spend maybe one hour or two hours out of their day with that individual and helping them out. In the middle stages, that might now become a longer job, because it really does become, say four hours or eight hours. In the late stages it's now becoming a full-time job where that individual requires full supervision. They can't really fend for themselves. They can't feed themselves, they can't toilet, they can't, again, get dressed and groom themselves in an appropriate fashion. So, now someone has to oversee all of those things. Memory has probably has become so severe where oftentimes an individual is in a state in which they're aware of who they are sometimes, but wouldn't be aware of say, the date, the place, where they're at, and so on. Oftentimes now the biggest challenge, clinically, is the behavioural manifestations that pop up in the late stages. An individual might now lose their ability to communicate fully; they might just groan, might not be able to ambulate anymore, or walk, get up, or otherwise. Literally, in the late stage of this illness, the body becomes so weakened that often times lower respiratory infections, say pneumonia, will often times do in the individual and they will die. So literally, this is an illness that kills people, and again, pushes them back into infancy and then lays them bare until their body all of a sudden becomes so weak and frail that they do die.
What are some of the dangers of someone with Alzheimer's in society?
The individual that doesn't get appropriate attention might be out there driving, exposing themselves to danger, lacking the ability to handle their car in a solid fashion or might endanger somebody else out on the road. So often, individuals with Alzheimer's disease that have now progressed a little bit further should always be evaluated for their ability to drive. In addition to that, the individual that becomes forgetful might wander, get lost, all of a sudden stray away from their neighborhood and may get lost or dis-orientated. So imagine the anxiety, the frustration or the fear that somebody all of a sudden finds that they can't find their way back to a secure shelter.
How common is Alzheimer's disease?
Alzheimer's disease is, unfortunately, not uncommon. We know that the prevalence rates right around 5 to 7 percent in individuals over the age of 65. However, individuals over the age of 85, it's close to halfthat actually might suffer from this illness. So as I mentioned earlier, advancing age is the biggest risk factor. Now, other very important points are that this illness is growing at a huge rate. In the past we used to cite numbers of about four and a half million Americans being affected by this illness. As of about a month and a half ago, the current numbers are 5.1 million Americans right now being affected by this illness. By the year 25, we guess that it's going to be closer to 16 million individuals. Why? Well, it turns out that we're living longer. As doctors, we've actually managed to do a better job about addressing medical co-morbidity. So we can fix other things better. So people live longer. But also, the baby boomers have gotten older, and as a consequence of that, there's a big increase in individuals who are older, and as a consequence of that, the growth in this illness.
Is memory loss a normal part of aging?
All our memory start to decline in our mid-20's, and this becomes more pronounced in our mid-40's. However, individuals with Alzheimer disease don't just have a subjective sense of memory loss. They also have a situation where by their ability to do things, to work or to socialize, have now become impaired to the point where other people notice. Those progressively get worst. This is certainly more than what age related memory decline would be expected to do.
