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Wednesday 31 December 2014


Alzheimer’s disease (AD)


Alzheimer’s disease was first identified more than 100 years ago, but research into its symptoms, causes, risk factors and treatment has gained momentum only in the last 30 years. Although research has revealed a great deal about Alzheimer’s, the precise changes in the brain that trigger the development of Alzheimer’s, and the order in which they occur, largely remain unknown. The only exceptions are certain rare, inherited forms of the disease caused by known genetic mutations.

In 2010, there were between 21 and 35 million people worldwide with AD. It most often begins in people over 65 years of age; although 4% - 5% of cases are early-onset Alzheimer's which begin before the age of 65. It affects about 6% of people 65 years and older.  In 2010 dementia resulted in about 486,000 deaths. It was first described by, and later named after, German psychiatrist and pathologist Alois Alzheimer in 1906. In developed countries, AD is one of the costly diseases.




Studies of selected risk or protective factors for cognitive decline and AD have been published, but it is not clear whether the results of these previous studies are of sufficient strength to warrant specific recommendations for behavioural, lifestyle, or pharmaceutical interventions / modifications targeted to these endpoints.

The major risk factor for AD is age, with the prevalence doubling every 5 years after the age of 65. Most estimates of the prevalence of AD are about 2.3 million for individuals over age 70, but some estimates are as high as 5.3 million individuals over the age of 65. The number of individuals with mild cognitive impairment exceeds the number with AD. These individuals have mild impairment in cognition or daily functions that does not meet the threshold for a diagnosis of dementia, but they are at increased risk for development of AD, which makes them a prime target for intervention protocols.

Dementia is a loss of cognitive abilities in multiple domains that results in impairment in normal activities of daily living and loss of independence. Alzheimer’s disease (AD) is the most common cause of dementia, responsible for 60 to 80 percent of all dementia. AD causes severe suffering for patients, including progressive functional impairment, loss of independence, emotional distress and behavioural symptoms. 

Families and caregivers often experience emotional and financial stress.


What is dementia ?

Dementia is the umbrella term used to describe various conditions which cause brain cells to die, leading to the progressive deterioration in memory and the ability to carry out everyday activities such as washing, dressing, eating, and completing complex tasks. Dementia may also affect a person’s mood and personality. There are many different types of dementia but Alzheimer’s disease and vascular dementia are the most common forms.

What is Alzheimer’s disease ?

Alzheimer’s Disease is a progressive neurological condition characterised by the build up of proteins in the brain called ‘plaques’ and ‘tangles’. These proteins gradually damage and eventually destroy the nerve cells. This can make it more and more difficult to remember, reason, and use language. The person may become disorientated and have increasing difficulty with simple daily tasks such as using the phone, making meals or managing money. 

Today, many senior citizens in the society have dementia, of which Alzheimer’s disease is the most common form. The risk of developing Alzheimer’s disease increases with age with its prevalence rising from approximately 1% in people under 65 years old to more than 25% for those over 80 years. Although rare and more commonly associated with older age, Alzheimer’s disease can also occur in people in their 40’s and 50’s.


What are the early signs of Alzheimer’s disease ?

Although the early signs and symptoms of Alzheimer’s disease may vary from person to person, increasing memory loss over time is often the first noticeable symptom.

Below is a list of 10 common signs of early stage Alzheimer’s disease:

Getting stuck for words or having language difficulties

Forgetting things – names, dates, places, faces

Loss of interest in starting projects or doing things

Difficulty in solving problems or doing puzzles

Difficulty in performing everyday tasks

Misplacing things regularly

Poor or decreased judgement

Changes in mood and behaviour

Disorientation in familiar surroundings

Changes in personality


Dementia : Definition and Specific Types 

Physicians often define dementia based on the criteria given in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). (1) To meet DSM-IV criteria for dementia, the following are required :

Symptoms must include decline in memory and in at least one of the following cognitive abilities :

Ability to speak coherently or understand spoken or written language

Ability to recognize or identify objects, assuming intact sensory function

Ability to perform motor activities, assuming intact motor abilities and sensory function and comprehension of the required task

Ability to think abstractly, make sound judgments and plan and carry out complex tasks.

The decline in cognitive abilities must be severe enough to interfere with daily life.

Symptoms of Alzheimer’s disease

Alzheimer’s disease affects people in different ways. The most common symptom pattern begins with a gradually worsening ability to remember new information. This occurs because the first neurons to die and malfunction are usually neurons in brain regions involved in forming new memories. As neurons in other parts of the brain malfunction and die, individuals experience other difficulties. The following are common symptoms of Alzheimer’s :

Memory loss that disrupts daily life

Challenges in planning or solving problems

Difficulty completing familiar tasks at home, at work or at leisure

Confusion with time or place

Trouble understanding visual images and spatial relationships

New problems with words in speaking or writing

Misplacing things and losing the ability to retrace steps

Decreased or poor judgment

Withdrawal from work or social activities

Changes in mood and personality


Diagnosis of Alzheimer’s disease

A diagnosis of Alzheimer’s disease is most commonly made by an individual’s primary care physician. The physician obtains a medical and family history, including psychiatric history and history of cognitive and behavioural changes. The physician also asks a family member or other person close to the individual to provide input. In addition, the physician conducts cognitive tests and physical and neurologic examinations and may request that the individual undergo magnetic resonance imaging (MRI) scans. MRI scans can help identify brain changes, such as the presence of a tumour or evidence of a stroke that could explain the individual’s symptoms.

The cause of Alzheimer's disease is poorly understood as it is often considered as the effects of aging.  About 70% of the risk is believed to be genetic with many genes usually involved. Other risk factors include: a history of head injuries, depression or hypertension. The disease process is associated with plaques and tangles in the brain. A probable diagnosis is based on the history of the illness and cognitive testing with medical imaging and blood tests to rule out other possible causes. Initial symptoms are often mistaken for normal aging. Examination of brain tissue is needed for a definite diagnosis.  Mental and physical exercise and avoiding obesity may decrease the risk of AD. There are no medications or supplements with evidence to support their use.

No treatments stop or reverse its progression, though some may temporarily improve symptoms. Affected people increasingly rely on others for assistance often placing a burden on the caregiver; the pressures can include social, psychological, physical, and economic elements. Exercise programs are beneficial with respect to activities of daily living and potentially improve outcomes. Treatment of behavioural problems or psychosis due to dementia with antipsychotics is common but not usually recommended because of being little benefit and an increased risk of early death.

“By 2050, the number of people in the Asia Pacific Region suffering from dementia will rise to 71 million from 23 million in 2015 with India coming second only to China with over 12 million likely victims of dementia,” the report by Alzheimer’s’ Disease International (ADI)


This blog is dedicated to Alzheimer’s caregivers and the people who are involved in research to discover the right medicine for this health problem.

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