Alzheimer’s disease is a neurological disorder which causes memory loss and cognitive impairment by the death of brain cells.
It is the most prevalent form of dementia, accounting in the United States for 60 to 80 percent of dementia cases.
There were 6.8 million people living with dementia in the U.S. in 2013. Among those 5 million had an Alzheimer’s diagnosis. The numbers are to double by 2050.
Alzheimer’s is an disorder which is neurodegenerative. Symptoms are mild at first but they get more serious over time.
Fast facts on Alzheimer’s disease
- Alzheimer’s disease is the most common type of dementia.
- It happens when plaques containing beta amyloid form in the brain.
- As symptoms worsen, it becomes harder for people to remember recent events, to reason, and to recognize people they know.
- Eventually, a person with Alzheimer’s is likely to need full-time assistance.
Symptoms
To order to obtain an Alzheimer’s diagnosis, the person most have undergone a deterioration to cognitive or behavioral ability and results as opposed to how they were before. This deterioration continues to conflict with their ability to operate at work or in daily activities.
The cognitive impairment must be seen in two or more of the five areas of symptoms mentioned below:
1. Reduced ability to acquire and maintain new knowledge that, for example, can contribute to:
- repetitive questions or conversations
- misplacing personal belongings
- forgetting events or appointments
- getting lost on a familiar route
2. Impairments to reasoning, complex tasking, and exercising judgment, for example:
- poor understanding of safety risks
- inability to manage finances
- poor decision-making ability
- inability to plan complex or sequential activities
3. Impaired visuospatial abilities that are not, for example, due to eye sight problems. These could be:
- inability to recognize faces or common objects or to find objects in direct view
- inability to use simple tools, for example, to orient clothing to the body
4. Impaired speaking, reading and writing, for example:
- difficulty thinking of common words while speaking, hesitations
- speech, spelling, and writing errors
5. Changes in personality and behavior, for example:
- out-of-character mood changes, including agitation, apathy, social withdrawal or a lack of interest, motivation, or initiative
- loss of empathy
- compulsive, obsessive, or socially unacceptable behavior
If the number and severity of symptoms confirm dementia, the following factors can then confirm Alzheimer’s.
- a gradual onset, over months to years, rather than hours or days
- a marked worsening of the individual’s normal level of cognition in particular areas
If symptoms start or escalate over hours or days you should seek urgent medical treatment as this can suggest an acute disease.
Alzheimer’s is most likely when memory loss is a prominent symptom, especially in the field of learning and new knowledge being remembered.
Language challenges can also be a crucial early symptom, like failing to find the right words.
If the most influential visuospatial deficits are, these may include:
- inability to recognize objects and faces
- difficulty comprehending separate parts of a scene at once
- difficulty with reading text, known as alexia
The most famous executive disability deficits may have to do with reasoning, judgment and problem-solving.
Other early signs
Researchers released results in 2016 suggesting that an early signs of Alzheimer’s may be a shift of sense of humour.
Latest research indicates that Alzheimer’s manifestations, such as brain abnormalities, may already be present in midlife, while signs of the disorder occur only years later.
Early-onset Alzheimer’s disease
Early-onset familial Alzheimer’s disease, usually between the ages of 30 and 60, may affect younger people with a family history of the disease.
It constitutes fewer than 5 percent of all cases involving Alzheimer’s.
Stages
The progression of Alzheimer’s can be broken down into three main stages:
- preclinical, before symptoms appear
- mild cognitive impairment, when symptoms are mild
- dementia
The Alzheimer’s Association also identifies seven stages along a continuum of cognitive impairment, based on severity of the symptoms.
The scale varies from a state of no disability, through mild and moderate decline, ultimately reaching “extremely extreme decline.” A diagnosis typically does not become apparent until stage four, described as “mild or early Alzheimer’s.”
Alzheimer’s versus dementia
Dementia is a paragliding term for a range of conditions which include a loss of cognitive function.
The most prevalent form of dementia is in Alzheimer’s. This includes the development of plaques and tangles within the brain. Symptoms start slowly and will most likely involve a decrease in cognitive function and ability to speak language.
Huntington’s disease, Parkinson’s disease, and Creutzfeldt-Jakob disease are other forms of dementia. People may experience more than one form of dementia.
Diagnosis
There is no single Alzheimer’s disease test, but physicians can look at the signs and symptoms, take a history of medication, and rule out any disorders before diagnosis.
Researchers can also check the neurological function of the person, by checking their balance, senses, and reflexes, for example.
Other tests may include a blood or urine check, a brain CT or MRI scan, and depression screening.
Often the dementia symptoms are linked to an inherited illness like Huntington’s disease, and genetic testing can be performed.
The doctor must administer cognitive and memory tests after ruling out any potential factors, in order to determine the person’s ability to think and recall.
Cognitive assessment
To confirm a diagnosis of Alzheimer’s, the following must be present and severe enough to affect daily activities:
- gradual memory loss
- progressive cognitive impairment
Questions that may be asked to test cognitive ability include:
- What is your age?
- What is the time, to the nearest hour?
- What is the year?
- What is the name of the hospital or town we are in?
- Can you recognize two people, for example, the doctor, nurse, or carer?
- What is your date of birth?
- In which year did (a well-known historical event) happen?
- Name the president.
- Count backward from 20 down to 1
- Repeat an address at the end of the test that I will give you now (for example, “42 West Street”)
A number of assessment tools are available to assess cognitive function.
Genetic testing
In certain cases it might be necessary to do genetic testing.
A gene known as the APOE-e4 is associated with increased risk of developing Alzheimer’s in people over the age of 55.
Early use of this test may suggest the possibility of someone getting the disease or developing it. The study is controversial, however, and the findings aren’t absolutely accurate.
Emerging biological tests that allow the assessment of biomarkers in people who may be at risk for Alzheimer’s in the future.
Treatment
Alzheimer’s has no known remedy. Can’t stop the death of brain cells.
However, there are therapeutic interventions that can make it easier for people to live with the disease.
The following are critical components of dementia treatment according to Alzheimer’s Association:
- effective management of any conditions occurring alongside the Alzheimer’s
- activities and day-care programs
- involvement of support groups and services
Drug therapy
There are no disease-modifying medications available for Alzheimer’s disease, but there are several treatments that can reduce the symptoms and help improve quality of life.
Inhibitors of cholinesterase approved for symptomatic relief in the US include:
- Donepezil (Aricept)
- Rivastigmine (Exelon)
- Tacrine (Cognex)
A different kind of drug, memantine (Namenda), an NMDA receptor antagonist, may also be used, alone or in combination with a cholinesterase inhibitor.
Other therapy
As the individual is less able to live independently, the need for quality-of-life treatment becomes more important.
Results of a mouse study published in Nature in 2016 indicated that memories for people with early Alzheimer’s may one day be recovered.
Causes and risk factors
Alzheimer’s, like any form of dementia, is caused by brain cell death. It is a neurodegenerative disorder, meaning that over time there is gradual mortality of the brain cells.
In an Alzheimer’s individual the tissue has fewer and fewer nerve cells and connections.
Autopsies have shown that a person with Alzheimer’s nerve tissue in the brain has tiny deposits, called plaques and tangles, that build up on the tissue.
In the dying brain cells, the plaques are located and made of a protein known as beta-amyloid.
The tangles arise in the cells of the nerves and are made from another protein called tau.
Researchers do not completely understand why such improvements are taking place. There are known to be a variety of different factors involved.
The Alzheimer’s Association has created a 16-slide journey that visualizes what happens during the process of Alzheimer’s disease development. You will get into it here.
Risk factors
Unavoidable risk factors for developing the condition include:
- aging
- a family history of Alzheimer’s
- carrying certain genes
Modifiable factors that may help prevent Alzheimer’s include:
- getting regular exercise
- maintaining a healthy cardiovascular system
- managing the risk of cardiovascular disease, diabetes, obesity, smoking, and high blood pressure
- following a varied and healthful diet
- participating in lifelong learning and cognitive training
Some research indicate that remaining active mentally and socially may theoretically reduce the risk of Alzheimer’s.
Factors that increase the risk include:
- undergoing severe or repeated traumatic brain injuries (TBI)
- exposure to some environmental contaminants, such as toxic metals, pesticide, and industrial chemicals
In order to minimize the risk of TBI-related dementia, it is also necessary to wear a safety belt while traveling by car, to take care while playing contact sports, and to obey health instructions and recommendations to ensure sufficient rest and rehabilitation when an accident occurs.
A mild TBI tends to double the risk of dementia, while a extreme TBI raises the risk 4.5 fold.
