The Facts

Dementia is a gradual decline of mental ability that affects your intellectual and social skills to the point where daily life becomes difficult. Dementia can affect your memory and your decision-making ability, can impair your judgment and make you feel disoriented, and it may also affect your personality.

Alzheimer's disease is the most common form of dementia and affects about 5% of people over age 65. It occurs more often with advancing age, affecting 20% to 25% of people over the age of 80. About 5% to 10% of dementia is vascular dementia, also known as dementia caused by stroke. At least 10% of cases of dementia are due to a combination of Alzheimer's disease and multiple strokes.

Dementia isn't an acute condition that suddenly appears, and it usually does not require emergency treatment.


Dementia may be caused by a number of factors, such as:

  • alcoholism
  • brain injury
  • drug abuse
  • side effects to certain medications
  • thyroid function abnormalities
  • vitamin B12 deficiency

In some cases of dementia, it may be reversible or improved once the underlying cause has been treated.

Aging and a family history of dementia are risk factors for developing dementia. The following factors can also add to the risk of developing dementia:

  • high blood pressure
  • high cholesterol
  • diabetes
  • smoking

Unfortunately, when dementia is caused by conditions such as Alzheimer's disease, brain injury, or blood vessel changes, the changes that occur are irreversible.

Research into the cause and treatment of Alzheimer's disease is shedding new light and more hope every day. Several possible causes have been identified, including genetic factors, exposure to toxins, abnormal protein production, viruses, and difficulties in blood flow to the brain. Aging and heredity (genetic factors) are considered the greatest factors involved in the development of Alzheimer's disease.

Vascular dementia is caused by a series of strokes that leave areas of dead cells in the brain. This disorder may result in sudden, stepwise decline or a more gradual loss of mental ability. Short-term memory is usually affected first.

Symptoms and Complications

Many of us often experience forgetfulness. We may forget where we put the car keys or repeat the same story to a friend or family member. These behaviours are usually caused by the information overload of our busy, stressful lives - it doesn't mean that we're developing dementia. As people age, they may experience memory changes such as slowing of information processing. This type of change is normal. By contrast, dementia is progressive and disabling and not a normal part of aging.

The true symptoms of dementia are a progressive loss of memory and other mental abilities. Dementia results in impairment of a person's ability to perform usual tasks in everyday life. There may also be changes in behaviour or personality.

Symptoms of Alzheimer's disease include:

  • gradual loss of memory of recent events and lack of ability to learn new things
  • increasing tendency to repeat oneself, misplace objects, become confused
  • slow disintegration of personality, judgment, and social ability
  • increasing irritability, anxiety, depression, confusion, and restlessness

Symptoms of vascular dementia include:

  • sudden loss of memory or other mental functions
  • stroke symptoms such as paralysis, difficulty with language, loss of vision
  • changes in walking patterns (gait)
  • early loss of bowel or bladder control
  • sudden laughing or crying without reason

Making the Diagnosis

Dementia is diagnosed by the history of symptoms and physical examination. Your doctor may ask you a series of questions to assess cognition, which involves functions of the brain related to memory, recall, decision-making, language, recognition of objects used on a daily basis, and following directions.

Brain scans can show changes in brain structure. Brain scans such as CT (computerized tomography) or MRI (magnetic resonance imaging) may be used to help identify other conditions (e.g., stroke) that can cause dementia.

Absolute confirmation of the diagnosis can only be made by examination of brain tissue after a biopsy or an autopsy after death. If there's a family history of dementia, you may want to consult a doctor.

Treatment and Prevention

Treatment of Alzheimer's disease usually involves treating the declining memory and gradually worsening behavioural symptoms with a range of medications, including:

  • cognitive enhancing agents
  • tranquilizers
  • antidepressants
  • antianxiety medications
  • anticonvulsants

Medications such as donepezil*, rivastigmine, and galantamine may also be used to slow down memory loss. There is no medication that can halt or reverse the brain damage caused by Alzheimer's disease. However, there are medications that can relieve symptoms, and researchers are discovering many promising new medications that can delay symptoms of the disease.

Recent evidence has shown that strokes are a major contributor to the progression of Alzheimer's disease; therefore, preventing a stroke is important.

Prevention of stroke is the only potentially effective treatment for vascular dementia. If you have high blood pressure, transient ischemic attacks (TIAs), or have had a stroke, you should seek continued treatment for these conditions to minimize their recurrence.

The key to caring for and helping people with dementia is to focus on the many activities the person can still do. Encourage a person with dementia to continue daily routines and maintain social relationships as much as possible. Help them maintain a healthy lifestyle through exercise, proper nutrition, and fluid intake. Special diets and supplements are generally unnecessary.

If you are caring for someone with dementia, the following may be helpful:

  • reminders: Provide written lists of things to do including times, places, and phone numbers to help the person complete the task.
  • structure and stability: Minimize undue noise and disturbances to reduce anxiety.
  • establish routines: Daily and bedtime routines can reduce disorientation and anxiety.
  • speaking slowly and calmly: Present one thought or instruction at a time.
  • information card: Reduce the risk of wandering and getting lost by providing a pocket card with the person's name, address, and phone number.
  • safety: Make your home environment as safe as possible by keeping furniture in the same place, removing clutter, installing locks on medicine cabinets, and setting the water heater at a low temperature to avoid scalding.
  • driving: Don't allow someone with dementia to drive a vehicle. Drive them or arrange for rides wherever they need to go.

Caring for someone with dementia can be difficult. It requires understanding, patience, and compassion. Joining an Alzheimer's disease caregiver's support group in your community may be helpful.

Be prepared for the eventuality that your loved one's condition will deteriorate over time and additional full-time personal care may be needed. In some situations, placement in a nursing home is in the best interests of the individual and their family.


*All medications have both common (generic) and brand names. The brand name is what a specific manufacturer calls the product (e.g., Tylenol®). The common name is the medical name for the medication (e.g., acetaminophen). A medication may have many brand names, but only one common name. This article lists medications by their common names. For information on a given medication, check our Drug Information database. For more information on brand names, speak with your doctor or pharmacist.