Alzheimer's Disease
(Senile Dementia)
In this condition factsheet:
The Facts on Alzheimer's Disease
Alzheimer's disease has a major impact on the health of Canadians. About 570,000 Canadians suffer from some type of dementia (mental deterioration), and it is estimated that the annual cost to Canadians to care for those living with dementia is over $10.4 billion.
There will be almost 1 million Canadians living with dementia by the year 2030, largely because the "baby boom" generation (people born between 1946 and 1960) will have reached old age. The risk of developing Alzheimer's disease doubles every 5 years after the age of 65.
Exactly how and why Alzheimer's disease develops is still not understood. Somehow, cells are damaged and eventually die in different areas of the brain. The damaged areas of the brain contain abnormalities called beta amyloid plaques and neurofibrillary (or tau) tangles. The death of brain cells leads to dementia, characterized by memory loss, impaired judgment, and behavioural changes.
Eventually, the person loses their speech as well as their bladder and bowel control. People with Alzheimer's typically die of infections such as pneumonia or other medical problems. Most people live for about 3 to 12 years after diagnosis, but some have lived for up to 20 years.
Each case of Alzheimer's usually affects at least two lives: the person with the condition, and the patient's spouse or child who gradually becomes a full-time caregiver as the disease progresses. Caring for an individual with Alzheimer's can be demanding and stressful. Many caregivers must eventually face the difficult decision of placing their loved one in institutional care.
Causes of Alzheimer's Disease
With Alzheimer's, we look more at-risk factors than direct causes as these are unclear most of the time. The greatest risk factor for Alzheimer's is age, with most cases occurring after the age of 65.
There may be a genetic factor in Alzheimer's disease, since we know that while uncommon, it sometimes runs in families. Familial Alzheimer's disease (FAD) is the name given when Alzheimer's disease is clearly passed on from generation to generation in a family. It typically comes on before the age of 60, and the Alzheimer's gene turns up in many family members. However, FAD only explains a small portion of all Alzheimer's disease cases. The most common form of Alzheimer's disease, sporadic Alzheimer's disease, may also run in families, but to a much lesser degree. It usually affects people after the age of 65.
Even if no one in your family has had Alzheimer's, you can still develop Alzheimer's disease.
Other possible risk factors include:
- head injury: studies show that people who have suffered concussions are more likely to develop Alzheimer's later on.
- gender: women are more likely than men to suffer from Alzheimer's (this is due to the increased life expectancy of women).
- education: Research suggests that better educated people are less prone to Alzheimer's. Those who already have the disease do better if they keep mentally active – an unused brain may deteriorate faster.
- smoking: smokers are more likely to develop Alzheimer's disease compared to non-smokers. They are also more likely to develop other types of dementia.
- prions: some scientists speculate that prions, tiny infectious particles made of protein, may be involved in Alzheimer's disease by infecting the brain.
- cardiovascular disease risk factors: many conditions that affect the heart and blood vessels (e.g., high blood pressure, high cholesterol, diabetes, obesity) are associated with an increased risk of developing Alzheimer's disease and other types of dementia.
Symptoms and Complications of Alzheimer's Disease
Mild forgetfulness is normal with advancing age, but healthy older people are usually good at remembering what's most important to them. There is reason for concern if they start forgetting what they were just doing, get lost in their own neighbourhood, or start displaying uncharacteristic or inappropriate behaviour. If your loved one is always misplacing their keys, it may mean nothing. If they start leaving them in the fridge or the sugar bowl, it may be cause for concern.
One of the most recognizable symptoms of Alzheimer's disease is a speech problem, such as a person choosing the wrong words, or not understanding simple sentences. Problems with numbers are also common. These are the most reliable signs of early-stage Alzheimer's disease. Other early signs include forgetfulness about recent events (loss of short-term memory), trouble with tasks such as housework or paying taxes, and poor judgment.
In the later stages, people with Alzheimer's disease begin to have trouble caring for themselves and recognizing friends or loved ones. They may become confused, agitated, or aggressive.
The Alzheimer's Society of Canada lists these 10 warning signs to be aware of:
- memory loss that affects day-to-day function
- difficulty performing familiar tasks
- problems with language
- disorientation of time and place
- impaired judgment
- problems with abstract thinking
- misplacing things
- changes in mood and behaviour
- changes in personality
- loss of initiative
