Health and Wellness Blog

First described in 1906 by German psychologist Alois Alzheimer, Alzheimer's disease is incurable, degenerative and fatal. It attacks the brain and it is the most common cause of dementia. It is most commonly diagnosed in people over 65, although early-onset Alzheimer’s can occur much earlier. 

Prevalence
Over 300,000 Canadians suffer from some type of dementia, over 60% of these have been diagnosed with Alzheimer’s disease (source). The government estimates that, by the year 2031 — when most Baby Boomers will reach 60 — over 750,000 Canadians will suffer from dementia. (more Canadian statistics)

Worldwide, an estimated 26.6 million people have been diagnosed with Alzheimer'sdisease (as of 2006). Four times this number are expected by 2050 (source).

Alzheimer’s is a devastating disease, affecting people with the disease as well as their spouses and children, who gradually assume a full-time caregiver role. This role is both demanding and stressful, eventually forcing families to place their loved ones in a long-term care facility. For more information on coping, contact your local Alzheimer society.

Symptoms
The early symptoms of Alzheimer’s disease very closely resemble normal age-related changes to the brain, or those caused by stress:

• it becomes harder to learn new things (short-term memory loss)
• you repeat yourself, misplace things, become confused
• you have difficulty using language
• you may become disoriented (time or place)
• your personality may change, or you may become more irritable, anxious, depressed, confused or restless
• you may develop poor judgement or have trouble understanding abstract things
• you lose your initiative (become very passive)

In the earliest stage (predementia), the most noticeable effect is memory loss and, in particular, difficulty in remembering recently-learned facts and in acquiring new information. It sometimes also reduces the ability to remember meanings or to grasp relationships between concepts (semantic memory).  There may be some effect on the ability to pay attention, to plan, to be flexible or to think abstractly. It may also cause a change in personality, a decline in judgment and in social ability. Apathy, one of the most persistent symptoms of the disease, makes its appearance in the predementia stage.

Diagnosis
Alzheimer disease develops over a long period, and may remain undiagnosed for years.

Generally, increasing difficulties in learning and remembering are the main clues leading a healthcare practitioner to suspect Alzheimer’s disease. Difficulties with language (shrinking vocabulary, speaking with less fluency), perception (agnosia) or motor functions (apraxia, the person may become clumsier or have trouble planning) may also indicate the presence of the disease. Changes in behaviour are another clue.

There are no definitive tests for Alzheimer's disease, which is usually diagnosed by eliminating other possible causes for dementia. Once symptoms become noticeable, a number of behavioural assessments and cognitive tests are performed, often including a brain scan. (more information)

As the disease progresses, people become confused, irritable and possibly aggressive, and prone to mood swings. They begin to lose the ability to communicate. Long-term memory begins to fail, and the person begins to withdraw as they lose senses. Bodily functions gradually decline (such as the ability to swallow, for example), until they are eventually lost and the person dies.

Once diagnosed, the life expectancy is generally about seven years. (source)

Causes
We still don’t know what causes Alzheimer’s disease, but we do know that it damages brain cells, eventually causing them to die. It is the death of brain cells that causes the characteristic dementia.

There may be a genetic factor, since some types tend to run in some families, and research indicates that the disease is associated with plaques and tangles in the brain. It may be caused by something in the external environment (water, soil, air), or it may be caused by something in the body. (source).

Some potential risk factors include(source: Healthy Ontario.  Alzheimer’s disease (undated).):

• head injury: concussions increase the risk later on in life

• vascular disease: coexisting small strokes may increase the risk and severity of memory problems
• inflammation: people with arthritis are less likely to get Alzheimer's, possibly because of the medications used to reduce inflammation in arthritis
• gender: today, women represent 72% of all cases of Alzheimer’s disease
• education: better-educated people are less prone to Alzheimer's (people with the disease do better if they keep mentally active, suggesting that an unused brain may deteriorate faster)
• toxins: the link between Alzheimer’s disease and toxins such as aluminum is controversial and unproven
• prions: some scientists think that prions (tiny infectious particles made of protein) may be involved in Alzheimer's disease by infecting the brain

Prevention
Studies into the prevention of Alzheimer's disease have not been conclusive. Mental stimulation, exercise and a balanced diet are often recommended, both to prevent and manage the disease.

The Alzheimer Society of Canada recommends taking steps early to protect your brain:

• challenge your brain: actively use your brain every day (play games, do puzzles, learn something new like a language or a musical instrument)
• socialise: stay connected socially to stay connected mentally (call a friend, visit family, chat to the neighbours, volunteer, join a club or take a class)
• make healthy lifestyle choices: eat well, get plenty of exercise, sleep enough, control your stress, avoid smoking and excessive alcohol consumption
• protect your head: brain injuries — especially repeated concussions — may increase your risk (wear a helmet, avoid falls, drive safely and wear a seatbelt)

Donna MacLeod, for the Consumer Health Information Service at Toronto Public Library

Related links

Websites

• Alzheimer Society of Canada website
• Alzheimer’s Association (US) website 
• Alzheimer's Society (UK) website
• Mayo Clinic. Alzheimer Center.
• US National Institutes of Health. NIH Seniors. Alzheimer's disease. (2007)