Alzheimer's Disease Research Paper

Brittany Shider
Alzheimer’s Disease
B398: Brain Mechanisms and Behavior
29 April 2010

ALZHEIMER’S DISEASE Alzheimer’s disease is a brain disease that is the most common form of dementia (Alzheimer’s Association, 2010). Alzheimer’s disease counts for approximately 65 % of all dementias. Alzheimer’s disease affects one’s memory and allows them to forget important information that happened throughout their lifetime. Alzheimer’s disease is also called Senile Dementia of the Alzheimer Type (SDAT) and just Alzheimer’s. Alzheimer’s disease was first discovered by a German Psychiatrist and neuropathologist, Dr. Alois Alzheimer, whom the disease was named after. There are millions of people who are living with Alzheimer’s disease today.
There are much as 5 million who are suffering from this disease. According to Alzheimer’s Association (2010), Alzheimer’s disease destroys many brain cells, causing memory loss and problems with thinking and behavior severe enough to affect work, lifelong hobbies, or social life. According to Medicine Net (2010), many scientists believe that Alzheimer’s disease results from an increase in the production or accumulation of a specific protein called a beta-amyloid protein, in the brain that leads to nerve cell death. Alzheimer’s is a very fatal disease and it gets worst over time. Alzheimer’s is the seventh leading cause of death in the United States. Alzheimer’s is the most common form of dementia. Dementia is the loss of memory and other intellectual abilities. There are two broad categories of dementia, called degenerative and nondegenerative dementia. Degenerative dementias are pathological process that are primarily intrinsic to the nervous system and tend to affect certain neural systems selectively. Nondegenerative dementias are a heterogeneous group of disorders with diverse etiologies, including vascular, endocrine, inflammatory, nutritional deficiency, and toxic conditions (Kolb
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& Whishaw, 2009). Alzheimer’s disease is categorized as a degenerative dementia. Alzheimer’s makes up approximately 50-80 % of dementia cases. As of today, there is not a cure for Alzheimer’s disease. Although there is not a cure, many people can be given treatment to reduce their symptoms of Alzheimer’s disease. There are many symptoms that lead to Alzheimer’s disease. According to Mayo Clinic (2010) symptoms that are associated with Alzheimer’s disease includes memory loss, problems with abstract thinking, difficulty finding the right word, disorientation, loss of judgment, difficulty performing familiar tasks, and personality changes. The personality changes that people may have is mood swings, distrust in others, stubbornness, depression, social withdrawal, anxiety and increased aggressiveness. Among with these symptoms, other warning signs for Alzheimer’s disease are having trouble understanding visual images and spatial relationships, new problems with words in speaking or writing. Also misplacing things and losing the ability to retrace steps, withdrawal from work or social activities, and decreased or poor judgment are also warning signs for having Alzheimer’s disease. The most common sign in Alzheimer’s disease is memory loss. Patients usually forget recently learned information and forgetting important dates and events. Patients ask the same information over and over again and they rely on memory aides such as note cards or electronics and sometimes family members. Alzheimer’s patients may also experience changes in their ability to develop and follow a plan or work with numbers (Alzheimer’s Association, 2010). They may have a problem of
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keeping track with bills and they will have difficulty concentrating and taking more time to do things than they did before. It is also harder to complete tasks if one has Alzheimer’s. Some may have trouble driving a vehicle, working at a job, or remembering daily chores. Patients with Alzheimer’s can also be disoriented with dates, telephone numbers, or television channels. It is usually harder for patients with Alzheimer’s understand something that is not happening immediately. Some people may forget where they are, how did they get there, and who are there with them. Vision impairment is also an issue for those with Alzheimer’s disease. People may have difficulty reading, or visualizing colors and signs. People with Alzheimer’s may also have trouble communicating and engaging in conversations with others. They may stop in the middle of the conversation and don’t know how to continue or they may repeat information. Patients may struggle with their vocabulary and find it difficult to recall the right words. A person with Alzheimer’s can also misplace belongings in unusual places.
Sometimes they may accuse someone of stealing it. Alzheimer’s patients can also make poor judgment when dealing with money or anything financial. A person that has Alzheimer’s may also tend to be antisocial from others. They may not want to engage in any sports, social activities, or hobbies. Most of these patients tend to avoid being social because of the changes they have experienced. The personalities and moods may also change with a person who has Alzheimer’s disease. They may become depressed, suspicious, fearful, or confused. They may get easily upset at others especially if they are out of their comfort
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Besides of not creating a cure for Alzheimer’s, there are no factors that have caused Alzheimer’s. There have not been any successful researches that can determine the cause of Alzheimer’s disease. Even though researchers can not understand what causes Alzheimer’s, it is clear of how it is affected on brain tissue. Alzheimer’s kills and damages many brain cells. The two most familiar brain cells that it damages are plaques and tangles (Mayo Clinic, 2010). Plaques are clumps of harmless protein called beta-amyloid that interferes with communication between the brain cells. Tangles are consisted of a protein called tau that undergo alterations and allow the brain cells to become twisted (Mayo Clinic, 2010). There are many risk factors for developing Alzheimer’s disease. Risk factors include age, hereditary, sex, lifestyle, cognitive impairment, and education levels. Alzheimer’s disease mostly affect people who are over the age of 65, but it can affect those younger than 40. There are approximately 5 % of people between the age of 65 and 70 who has Alzheimer’s disease. The percentage increases tremendously for those who are 85 years of age. It is approximately 50 % of people who develops Alzheimer’s over the age of 85. The early-onset stage of Alzheimer’s disease occurs before age 60, and the late-onset stage occurs after the age of 60. The early-onset stage is usually rare, and it represents fewer than 5% of all Alzheimer’s patients (Brannon & Feist, 2007). A person’s heredity can also increase the risk of developing Alzheimer’s. Those who had a parent, sister, or brother who had Alzheimer’s are at risk for the developing the disease also. It is also determined that women are more likely to have Alzheimer’s than men. Women are more

5 likely to develop this disease because they tend to live longer than men. Many people who have cognitive impairment that is not classified as dementia usually develops Alzheimer’s disease. People should maintain a good lifestyle that will not increase their risk of developing Alzheimer’s along with any other diseases.
Those who have high blood pressure, high cholesterol and poorly controlled diabetes can increase their risk of developing Alzheimer’s disease. Also, some studies believe that not only caring for your physical body, but exercising your mind mentally will also reduce the risk of Alzheimer’s disease (Mayo Clinic, 2010). Research also shows that people who have more education and uses their brain to create more synapses can also reduce the risk of Alzheimer’s disease. According to Brannon & Feist (2007), the most common psychiatric problem among Alzheimer’s patients is depression, with as many as 20% of patients exhibiting symptoms of clinical depression. Depression is a major risk factor for Alzheimer’s disease. Negative moods are common among people in the early stages of Alzheimer’s disease. Those that retain these moods find their deterioration distressing and respond with feelings of helplessness and major
depression. The memory loss that an Alzheimer’s patient endures first appears in the form of small, ordinary failures of memory, which is related to the early stages of Alzheimer’s disease. This memory loss progresses to the point that Alzheimer’s patients fail to recognize their family members. They also forget how to perform daily self-care. In the early stages of Alzheimer’s, the patients are usually aware of their memory failures, but as it progress they become unaware of it. 6
Paranoia and suspiciousness may also relate to the cognitive impairments of Alzheimer’s disease. Alzheimer’s patients usually forget where they put their belongings at, and because they can not find it, they accuse others for taking them. When Alzheimer’s patients express this behavior, it usually results in verbal aggression. Verbal aggression was noted in approximately 37% of Alzheimer’s patients and physical aggression was noted in approximately 17% of Alzheimer’s patients. Many doctors can diagnose over 90% of Alzheimer’s cases. According to Brannon & Feist (2007), Alzheimer’s can be diagnosed definitively only through autopsy, but Alzheimer’s patients show behavioral symptoms of cognitive impairment and memory loss that lead to a provisional diagnosis. There are a great number of tests that can help distinguish Alzheimer’s disease from other causes of memory loss. The three most popular tests are lab tests, neuropsychological tests, and brain scans. Lab tests are blood tests that are done to help doctors rule out other causes of dementia, such as thyroid disorders or vitamin deficiencies (Mayo Clinic, 2010). Neuropsychological tests are very extensive and take many hours to complete. This type of testing helps detect Alzheimer’s and other dementias at an early stage. There are three basic types of brain scans. Doctors can either perform a magnetic reasoning image (MRI), a computerized topography (CT), or a positron emission topography (PET). A magnetic reasoning image uses radio waves and a strong magnetic field to produce detailed images of the brain. A computerized topography is when x-rays are passed throughout the body from various angles. The computer then uses this information to create cross-sectional
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images of the entire brain. A positron emission topography is when a doctor injects a patient with a low-level radioactive material, which binds to chemicals that travel to the brain. This procedure helps to show which parts of the brain that are not functioning properly. All of the tests are painless and takes approximately one hour to complete. Alzheimer’s disease is characterized by the loss of neurons and synapses in the cerebral cortex and other regions of the brain. MRIs and PETs have documented reductions in the size of specific brain regions in patients as they progressed from mild cognitive impairment to Alzheimer’s disease (Mayo Clinic, 2010). Plaques and tangles are visible by microscopy in brains of those who are diagnosed with Alzheimer’s disease. According to Mayo Clinic (2010), Alzheimer 's disease has been identified as a protein misfolding disease, called proteopathy, caused by accumulation of abnormally folded A-beta and tau proteins in the brain. The plaques that affect Alzheimer’s disease in the brain are made up of small peptides called beta-amyloids. The neuritic plaques are found in the cerebral cortex. A beta-amyloid is a fragment from a larger protein called amyloid precursor protein, also called APP. The fragments include dendritic and axonal processes and other components of neural cells. APP is a transmembrane protein that penetrates through the neuron’s membrane. Tangles, also called paired helical filaments, are also found in the cerebral cortex and in the hippocampus. The posterior half of the hippocampus is affected more rigorously than the anterior half. According to Kolb & Whishaw (2009), light-microscopic examination has shown that the filaments have a double-helical configuration. They have been described mainly in human tissue and have been observed not only in Alzheimer’s patients but also in patients with
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Down syndrome, patients with Parkinson’s disease, and patients with other dementias (Kolb & Whishaw, 2009). The limbic system suffers the most difficult degenerative changes in Alzheimer’s disease. The entorhinal cortex is affected earliest and the most severely in the limbic system. Researchers believe that the entorhinal cortex shows the clearest evidence of cell loss. The entorhinal cortex is the major source in which information from the neocortex gets to the hippocampus and is then sent back to the neocortex. Damage to the entorhinal cortex results in major memory loss; and since memory loss is the earliest symptom for Alzheimer’s disease, it is most likely caused by the degenerative changes that take place in this area of the limbic system (Kolb & Whishaw, 2009). There are many empirical studies and experiments that have been conducted on Alzheimer’s patients and how have it affected their cognitive processes. Researchers conduct these studies to help determine the cause of Alzheimer’s disease and how they can use different treatment to cure this disease. Although there is not a cause and cure for this disease, researchers are still participating in experiments to resolve this issue. According to Weih, Degirmenci, Kreil, and Kornhuber (2010), since life expectancy is growing in most countries and age is the most important risk factor for AD, there will be an increase of incidence and prevalence of AD within the next decades. It has been hypothesized that physical activity is a protective factor against cognitive decline and Alzheimer’s disease. Most studies showed that individuals with some sort of physical activity had a reduced risk of

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Alzheimer’s disease. Individuals with physical activity had a relative risk of Alzheimer’s disease of 0.59, compared to individuals with no physical activity. The risk reduction for Alzheimer’s disease was higher than other neurodegenerative diseases like Parkinson’s disease, which was 0.82, or for other dementia types which was 0.72. According to Weih et al (2010), if physical activity were performed by a significant amount in the midlife population, they would hypothesize that the increasing burden of Alzheimer’s disease due to an aging population could possibly be ameliorated. Researchers also conducted studies to determine the effects of normal aging and how Alzheimer’s disease is affected by emotional memory. According to Kensinger, Brierley, Medford, Growden, and Corkin (2002), Alzheimer 's disease results in atrophy of limbic structures, whereas normal aging relatively spares limbic regions but affects prefrontal areas. The authors hypothesized that Alzheimer’s disease would reduce all enhancement effects, whereas aging would disproportionately affect enhancement based on emotional context. The amygdale in the limbic system shrinks when one has Alzheimer’s disease. The neuritic plaques and neurofibrillary tangles are plentiful in the amygdala. Some researchers have reported emotional enhancement in patients with Alzheimer’s disease. According to Kensinger et al (2002), although Alzheimer’s patients also have hippocampal atrophy, it appears that amygdaloid and not hippocampal damage accounts for the emotional enhancement reductions: Amygdaloid volume, rather than hippocampal volume, best predicts memory for an emotional event in patients with Alzheimer’s disease. 10
One focus of the study was to examine whether patients in the early stage of Alzheimer’s disease would show impaired memory enhancement for emotional items compared to neutral items. The finding would indicate whether damage to the amygdala in Alzheimer’s disease is sufficient to cause reductions in the emotional-memory enhancement effect. Alzheimer’s patients could show an uneven impairment in remembering negative stimuli (Kensinger et al, 2002), The results of this study showed that older adults and Alzheimer’s patients showed reduced memory enhancement based on emotion (Kensinger et al, 2002). Patients who had Alzheimer’s disease showed no memory enhancement on any task. The results provides support for the hypothesis that the amygdala is used to boost memory for positive as well as negative stimuli, such that AD patients, who are known to have severe atrophy of the amygdala do not show the memory advantage for either category of stimuli (Kensinger et al, 2002). As stated, there is no cure for Alzheimer’s disease, but drug and non-drug treatments may help with both cognitive and behavioral symptoms. Researchers are looking for new treatments to alter the course of the disease and improve the quality of life with people who have dementia (Alzheimer’s Association, 2010). There are two types of symptoms for Alzheimer’s disease. The two symptoms are cognitive and behavioral/psychiatric. The cognitive symptoms affect memory, language, planning, judgment, ability to pay attention and other thought processes. The behavioral/psychiatric symptoms affect the way we feel and act (Alzheimer’s Association, 2010). There are many treatments that are associated with the cognitive symptoms. According to Alzheimer’s Association (2010), The U.S. Food and Drug Administration (FDA) have
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approved two types of medications to treat cognitive symptoms of Alzheimer 's disease. These drugs affect the activity of two different chemicals involved in carrying messages between the brain 's nerve cells. The two medications include Cholinesterase inhibitors and Memantine. Cholinesterase inhibitors prevent the breakdown of acetylcholine, a chemical messenger for learning and memory. Cholinesterase inhibitors support communication among the nerve cells by keeping acetylcholine levels high. They also delay the worsening of symptoms for 6 to 12 months for half of the people who have Alzheimer’s disease. The three most familiar cholinesterase inhibitors are donepezil, rivastigmine, and galantamine. Donepezil help treats all stages of Alzheimer’s disease. Rivastigmine help treat mild to moderate Alzheimer’s, and galantamine also treat mild to moderate Alzheimer’s (Alzheimer’s Association, 2010). Memantine works by regulating the activity of glutamate, a dissimilar messenger chemical involved in learning and memory. Memantine was approved in 2003 for treatment of moderate to severe Alzheimer’s disease. It is also the only drug of its type approved to treat Alzheimer’s disease. Memantine temporarily delays the worsening of symptoms for some patients. The benefit of taking Memantine is similar to taking cholinesterase inhibitors (Alzheimer’s Association, 2010). For many patients, Alzheimer’s disease affects the way they feel and act and how it impacts their memory and other thought processes. In different stages of Alzheimer’s disease, people may experience emotional distress, physical or verbal outbursts, restlessness, delusions, and hallucinations. Many patients that have Alzheimer’s and their family members find these
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symptoms to be the most challenging and distressing effects of the disease (Alzheimer’s Association, 2010). There are two methods to managing behavioral symptoms. The two methods are using medications to treat the disease or using non-drug strategies. Non-drug strategies are usually the first choice that should be tried to treat this disease. Non-drug treatments include is first recognizing that the patient is not mean or rude, and that they are having further symptoms of the disease. Another method is understanding the cause of the disease and how the symptoms may relate to the experience of the person with the disease. Changing the person’s environment to resolve challenges and obstacles to comfort, security, and ease of mind is also another strategy (Alzheimer’s Association, 2010).
According to Alzheimer’s Association (2010), even though the chief cause of behavioral symptoms is the effect of Alzheimer 's disease on the brain, an exam may reveal treatable conditions that are contributing to the behavior. Treatable conditions include drug side effects, physical discomfort, and uncorrected problems with hearing or vision. The drug side effects can affect the patient’s behavior. Patients can have physical discomfort such as common illnesses that go undetected, pain from injections and constipation. Problems with one’s hearing or vision can cause confusion, frustration and a sense of isolation.
There are many situations that can affect the behavior of those with Alzheimer’s disease. Situations that affect behavior includes changes in the environment or caregivers, moving to a new residence such as a nursing home, admission to a hospital, misperceived threats, being asked

13 to bathe or change clothes, or fear and fatigue resulting from trying to make sense out of a confusing world (Alzheimer’s Association, 2010).
If the non-drug strategies do not help decrease the symptoms, then one should result by taking medications. Medications should target specific symptoms so their effects can be monitored. It is best for Alzheimer’s patients to start off by taking a low dose of a single drug. Effective treatment of one core symptom may help relieve other symptoms. Patients taking medications for behavioral symptoms must be closely monitored. Patients with dementia can result in serious side effects such as a stroke and increased risk of death from antipsychotic medications.
There are a number of medications that are used to treat behavioral and psychiatric symptoms of Alzheimer’s disease. Antidepressants are taken to reduce mood swings and irritability. Anxiolytics reduce anxiety, restlessness, resistance, and verbally disruptive behavior. Antipsychotic medications decrease hallucinations, delusions, aggression, agitation, hostility and uncooperativeness (Alzheimer’s Association, 2010).
There are many treatments that are very beneficial to decrease the symptoms of Alzheimer’s disease. Whether it’s taking different medications or engaging in non-drug treatment, they both help reduce the symptoms. Alzheimer’s disease can not be resolved overnight, but taking treatment will diminish the symptoms over a given period of time.
It can be very difficult to take care of patients that have Alzheimer’s disease. Patients who have Alzheimer’s usually rely on their family members to help care for them. Since taking care of a patient who has Alzheimer’s could be very challenging, there are ways that can help the
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family with this situation. Caring for a family member with a dementing disease such as Alzheimer’s creates a burden for families (Brannon & Feist, 2007). The problems of taking care of a patient with Alzheimer’s greatly disrupt family routine, require time and demand new skills.
Alzheimer’s caregivers frequently experience feelings of loss for the relationship that they once shared with the patient. These feelings of loss may begin with a patient’s diagnosis. However, only 19 % of those caring for someone with Alzheimer’s disease reported only strains. Most found positive aspects of their care giving, such as feelings of mastery and personal and spiritual growth (Brannon & Feist, 2007).
In conclusion, Alzheimer’s disease is a chronic illness that affects people’s lives everyday. Alzheimer’s disease is the loss of memory in the brain and portrays negative symptoms and side effects. There is not a cause or a cure for Alzheimer’s disease but researchers are conducting studies everyday to break this tradition. Alzheimer’s patients undergo many treatments to help decrease the effects of their disease. With the help of the treatment and support from their family and caregivers, the patients can move in a positive direction and manage their condition. Alzheimer’s disease is a serious illness and hopefully researchers and doctors can discover a cure for the prevention of this disease in the future.

References

Alzheimer’s Association (2010). Alzheimer’s Disease. Retrieved April 10, 2010 from http://www.alz.org/index.asp
Brannon, L. & Feist, J. (2007). Health Psychology: An Introduction to Behavior and Health. California: Thomson Wadsworth.
Kensinger, E., Brierley, B., Medford, N., Growdon, J., & Corkin, S. (2002). Effects of normal aging and Alzheimer 's disease on emotional memory. Emotion, 2(2), 118-134.
Kolb, B. & Whishaw, I. (2009). Fundamentals of Human Neuropsychology. New York: Worth.
Mayo Clinic (2010). Alzheimer’s Disease. Retrieved March 19, 2010 from http://www.mayoclinic.com/health/alzheimers-disease/DS00161
Medicine Net (2010). Alzheimer’s Disease. Retrieved March 19, 2010 from http://www.medicinenet.com/alzheimers_disease/article.htm
Weih, M., Degirmenci, Ü., Kreil, S., & Kornhuber, J. (2010). Physical activity and Alzheimer’s disease: A meta-analysis of cohort studies. GeroPsych: The Journal of Gerontopsychology and Geriatric Psychiatry, 23(1), 17-20.