Alzheimer's disease is the most common cause of dementia, affecting over 40 million people worldwide. And though it was discovered over a century ago, scientists are still grappling for a cure. Ivan Seah Yu Jun describes how Alzheimer's affects the brain, shedding light on the different stages of this complicated, destructive disease.
What are the other Names for this Condition? (Also known as/Synonyms)
- Early Onset Alzheimer Disease
- Primary Senile Degenerative Dementia
- Senile Dementia - Alzheimer's Type (SDAT)
What is Dementia of Alzheimer's? (Definition/Background Information)
- Dementia (NOS) is a type of disorder accompanied by a collection of symptoms that indicate brain impairment and loss of brain function. It leads to a progressive decline of all cognitive aspects such as behavior, memory, attention, analytic ability, thinking, and language skills.
- The onset of Dementia can be gradual or sudden. There can be a gradual deterioration of the brain’s abilities, due to age factor or an unexpected event like an accident or illness might cause Dementia.
- Alzheimer’s Disease (AD) is the most common cause factor for Dementia. As many as 80% of all Dementias are attributed to this factor.
- AD is a brain disorder of unknown origin that results in steadily worsening signs of memory loss, besides affecting one’s thinking and behavior.
Who gets Dementia of Alzheimer's? (Age and Sex Distribution)
- AD occurs past the age of 60-65 years. This happens frequently and is known as Late Onset Alzheimer’s Disease. It is infrequent below this age range. When it occurs below this age group, it is termed as Early Onset Alzheimer’s Disease.
- Usually, the female sex is slightly more prone to this disorder than male sex.
- No particular race or ethnic preference has been observed.
What are the Risk Factors for Dementia of Alzheimer's? (Predisposing Factors)
There is a host of factors that could potentially increase the risk for Alzheimer’s disease, and hence for Dementia associated with it. Some may be controlled, while others are unchangeable and often relentless:
- Age: Particularly people above the age of 50 are at greater risk.
- Genetic causes: Individuals having a family history of Alzheimer’s disease; particularly those having a close relative, or a sibling.
- Direct risk factors for Alzheimer’s include: High blood pressure, diabetes (type 2), high blood levels of the amino acid homocysteine (a condition termed as homocystinuria), depression, past head injury (which may have been prolonged).
- Individuals suffering from mild cognitive impairment; mild loss of memory and impairment of language, thinking skills; all due to old age.
- Food and lifestyle habits, such as smoking of tobacco, cholesterol (high levels of LDL), atherosclerosis due to fat build-up, eating less fruits and vegetables, seclusion from social life, and aloofness, and leading a sedentary life.
It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.
Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.
What are the Causes of Dementia of Alzheimer's? (Etiology)
Dementia, which develops from Alzheimer’s disease, has not been clearly understood. It is however thought that lifestyle, food, environmental conditions, and genetic make-up (sometimes), contribute towards AD development.
Based on speed of progression, Alzheimer's Dementia can be classified as:
- Slowly Progressive Dementia: When neurodegenerative disorders cause slowly progressing Dementia; and the nerve cells (neurons) lose their function over many years.
- Rapidly Progressive Dementia: A sudden advancement of the condition may occur, where more and more neurons die increasingly faster, causing a kind of brain shrinkage (cerebral atrophy).
What are the Signs and Symptoms of Dementia of Alzheimer's?
‘Dementia of the Alzheimer's Type’ presentations may be mild or severe, and they include:
- Progressive deterioration of the senses, memory loss, communication difficulties, incoherence
- Loss of basic motor (physical and spatial) skills; difficulty walking, maintaining balance, performing basic and routine activities becomes very challenging
- Changes in overall personality; regression or absence of reasoning/rationale, agitation, delusions, depression, aggression
- Extremely irrational mental/emotional/physical behavior (may be completely inappropriate for the situation), resulting in loss of social abilities, social awkwardness, and withdrawal
How is Dementia of Alzheimer's Diagnosed?
To examine for Dementia due to Alzheimer’s disease, a variety of tests are usually conducted. The evaluation is usually based on the set of signs and symptoms that are present. The main diagnostic tools include:
- Physical exam with a comprehensive evaluation of medical history, including collecting details on any underlying conditions/disorders and their progression
- Neurological and cognitive assessment: Checking intellectual ability, memory, mental health and function, language skills, judgment and reasoning, coordination and balance, reflexes, sensory perceptions (space, sight, hearing, touch)
- Psychiatric examination
- Imaging studies performed are: MRI scan of the central nervous system (brain and spine), CT scan (head), PET imaging of brain
- Blood analysis: Total blood count, blood chemistry, glucose, ammonia, blood gas analysis, electrolytes, vitamin levels
- Urine analysis: Screening for toxic substances, alcohol, determination of vitamin deficiencies
- Cerebrospinal fluid analysis
- Liver and kidney function tests
- Thyroid function tests, such as TSH, T3, and T4
- Electroencephalogram (EEG)
Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.
What are the possible Complications of Dementia of Alzheimer's?
Complications with ‘Alzheimer’s caused Dementia’ depend on the severity of the condition, age, and overall health of the individual. These include:
- Memory loss and neurological function impairment to a great extent, such that institutionalized care might be required for prolonged periods, or for the rest of an individual’s life. There is a progressive inability of the individual to take care of themselves, due to a complete degeneration of mental and emotional health.
- Loss of inhibition, spontaneous incontinence (involuntary bowel or bladder movement), loss of sleep, prone to fall-related injuries.
- Complete loss of personality causing paranoia, depression, irrational aggression/anxiety, delirium.
- The individual may become susceptible to opportunistic infections; organ failure chances are higher; due to a reduced sense of hygiene, decreased intake of food/nutrition. Often, these factors lead to an overall reduced lifespan.
- An individual may have persistent pain, which is often under-treated due to lack of proper communication between the individual and their healthcare providers.
- Feeding and swallowing problems; food may get blocked in the airways/lungs resulting in pneumonia, choking.
- Treatment medication may have significant side effects.
How is Dementia of Alzheimer's Treated?
Treatment of Dementia is based on its cause, severity of the condition, and associated signs and symptoms. Dementia management (due to Alzheimer’s disease) is undertaken on a case-by-case basis, and there is no standard treatment. Some of the methods include:
- Addressing general health problems that are mostly linked to mental balance and well-being. This includes the treatment of anemia, dietary or vitamin deficiencies, heart-related ailments, infections, thyroid disorders, hormonal imbalances, and regulating blood pressure
- Treatment of the underlying illness, to prevent progression of Dementia
- Ensuring that the individual has a nutritious diet with medical supplements (balanced diet that include proteins, fiber-rich fruits and vegetables, milk shakes, juices, and plenty of water)
- Ensuring that the individual is well-cared for in a safe environment (at home, or outside) and is under regular (and maybe constant) care and support
- Use of medications to control behavioral issues and prevent further loss of mental stability, like stimulants, mood stabilizers, cholinesterase inhibitors, NMDA receptor antagonists, antipsychotic drugs, sedatives, anti-depressants, etc. Many of these medications may cause side effects like nausea, stomach problems, drowsiness, and vomiting
- Home and work environment can be suitably modified to make it a lot safer and convenient for performing regular activities. This includes safety features normally designed for the physically challenged or the elderly, furniture rearrangement, and use of ramps
- Wheelchairs, walkers, braces, are used to provide physical support and promote mobility
- Hospitalization may be required (for short or long duration), depending on the condition of the individual. This is followed by regular check-ups
A healthcare provider may utilize the following treatment measures on a case-by-case basis. These are meant to provide mental and emotional support, and develop or retain communication skills:
- Psychiatric treatment
- Group therapy interactive sessions
- Support groups
How can Dementia of Alzheimer's be Prevented?
Prevention of Dementia is related to age of the individual, the causative agent, and other underlying conditions. Dementia caused by Alzheimer’s disease may not be preventable. Nevertheless, in almost all cases of the disorder with irreversible factors, the progression of the condition can be delayed or controlled, to some extent.
- Factors associated with diet, lifestyles like alcoholism, smoking, obesity, cholesterol levels, stress, nutritional deficiencies, hormonal problems, use of certain medications, and diabetes may be regulated and/or controlled.
- Any injuries to the brain, or the presence of brain tumors, have to be treated immediately, and adequate follow-up maintained. There is a possibility that these may significantly contribute to Dementia development, in the future.
- Individuals who fall into the high-risk category (and all others over the age of 60 years) should be encouraged to be socially active and physically fit (with regular exercising). A healthy diet rich in fruits, vegetables, fish, whole grains, and low in fats and sugar, is recommended.
- High-risk individuals should constantly maintain a healthy mind, by undertaking mentally stimulating activities like; reading/writing/teaching, solving puzzles, playing video games, listening to music, and learning new skills (painting, language, playing an instrument).
What is the Prognosis of Dementia of Alzheimer's? (Outcomes/Resolutions)
The prognosis for an individual with Dementia from Alzheimer’s, is based on a combination of many factors:
- Age of the adult
- Degree of severity; often rapidly progressing AD bring about a speedy decline in the condition of the individual
- General health and medical history
- Tolerance level/health of the individual, when subjected to various medications, their response to Dementia management
- Complications observed, if any
Normally, life-long management of the condition is necessary. Early detection and aggressive management of Alzheimer’s Dementia, with regular health checkups and supportive care are essential. This will prevent further rapid deterioration of the condition, and help sustain the quality of life.
Generally, with Alzheimer’s disease, an individual may live anywhere between 3-20 years, after the onset of the condition. Alzheimer’s that develop early and rapidly and progress at a faster pace, bring about the worst outcomes. Death results from infections, such as pneumonia, or failure of vital organs.
Additional and Relevant Useful Information for Dementia of Alzheimer's:
- There are voluntary organizations and support groups for Alzheimer’s Dementia that provides counsel, help, and understanding, to the affected individuals and families.
- Participation in social activities (like volunteering), getting involved in community teaching, joining online social groups, etc. are some of the other activities that should be encouraged to delay/decrease progression of the condition.
What are some Useful Resources for Additional Information?
References and Information Sources used for the Article:
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001748/ (accessed on 2/07/13)
http://www.mayoclinic.com/health/dementia/DS01131 (accessed on 2/07/13)
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001767/ (accessed on 2/07/13)
http://www.mayoclinic.com/health/alzheimers-disease/DS00161 (accessed on 2/07/13)
http://www.alz.org/alzheimers_disease_what_is_alzheimers.asp (accessed on 2/07/13)
Helpful Peer-Reviewed Medical Articles:
Alekseenko, A. V. (2013). [The potential role for sphingolipids in neuropathogenesis of Alzheimer's disease]. Biomed Khim, 59(1), 25-50.
Chan, K. Y., Wang, W., Wu, J. J., Liu, L., Theodoratou, E., Car, J., . . . Global Health Epidemiology Reference, G. (2013). Epidemiology of Alzheimer's disease and other forms of dementia in China, 1990-2010: a systematic review and analysis. Lancet, 381(9882), 2016-2023. doi: 10.1016/S0140-6736(13)60221-4
Epelbaum, S., & Dubois, B. (2013). [Subjective cognitive complaint. From anxiety to prodromal Alzheimer's disease?]. Rev Prat, 63(5), 651-654.
Pillai, J. A., & Cummings, J. L. (2013). Clinical trials in predementia stages of Alzheimer disease. Med Clin North Am, 97(3), 439-457. doi: 10.1016/j.mcna.2013.01.002
Teipel, S. J., Grothe, M., Lista, S., Toschi, N., Garaci, F. G., & Hampel, H. (2013). Relevance of magnetic resonance imaging for early detection and diagnosis of Alzheimer disease. Med Clin North Am, 97(3), 399-424. doi: 10.1016/j.mcna.2012.12.013
Rovio, S., Kåreholt, I., Helkala, E. L., Viitanen, M., Winblad, B., Tuomilehto, J., ... & Kivipelto, M. (2005). Leisure-time physical activity at midlife and the risk of dementia and Alzheimer's disease. The Lancet Neurology, 4(11), 705-711.
Erkinjuntti, T., Kurz, A., Gauthier, S., Bullock, R., Lilienfeld, S., & Damaraju, C. V. (2002). Efficacy of galantamine in probable vascular dementia and Alzheimer's disease combined with cerebrovascular disease: a randomised trial. The Lancet, 359(9314), 1283-1290.
Gregory, C., Lough, S., Stone, V., Erzinclioglu, S., Martin, L., Baron‐Cohen, S., & Hodges, J. R. (2002). Theory of mind in patients with frontal variant frontotemporal dementia and Alzheimer’s disease: theoretical and practical implications. Brain, 125(4), 752-764.