Dementia, also called major neurocognitive disorder, is a term encompassing different forms of cognitive function loss. These losses can affect memory, the ability to make sound judgment, language skills, reasoning, learning and comprehension skills, as well as emotional control and social skills. These can vary depending on the various types of dementia.
On the other hand, it is normal for your mental abilities to decline somewhat as you get older. Dementia is a gradual decline that occurs faster normal. It usually affects people over the age of 65. It can also affect the youngest, in which case it is called dementia praecox (or premature dementia).
The most common types of dementia are:
- Alzheimer's type dementia: caused by the destruction of neurons (60-70% of dementia cases)
- Lewy body dementia: an accumulation of proteins that make deposits in the brain (5-15% of dementia cases)
- Vascular dementia: a blood circulation problem that leads to the death of nerve cells (15-20% of dementia cases)
- Frontotemporal dementia: lesions in the frontal and temporal lobes
- Mixed dementia: Symptoms show the presence of more than one type of dementia
Causes of dementia
The exact cause of Alzheimer's has not yet been definitively identified. Many hypotheses are being researched. However, it seems that aging has a role to play since Alzheimer's mainly affects those over 65 and its predominance increases with age. In fact, around 5% of those aged 65 and over will be affected, while this figure increases to 20-25% for those aged 80 and over. Family history also seems to increase the risk of suffering from Alzheimer's. Therefore, if any members of your family have it or have had it, you might have genes that predispose you to developing the disease.
Lewy body dementia
Little is known about the causes of Lewy body dementia. It is likely genetic. We only know that a certain protein accumulates in the cells of the cerebral cortex and forms clumps called Lewy bodies. These clumps are thought to be responsible for cell death, which causes cognitive problems.
Vascular dementia is almost always secondary to a transient ischemic attack (TIA) or stroke (CVA). In these cases, a clot forms in the blood vessels of the brain and prevents blood from reaching the cells and delivering oxygen to them. For hemorrhagic strokes, the cause is the loss of blood through a hole in the artery. The lack of oxygen causes these cells to die. The loss of these cells can cause a sudden loss of mental ability after the incident. A slow, gradual loss is still possible.
The cause of this dementia is atrophy (decrease in volume) of the brain’s frontal and temporal lobes. It seems to be strongly linked to genetic mutations since there is a family history of dementia, often premature dementia, in 40-50% of cases.
Dementia can also be secondary to different things:
- Vitamin B12 deficiency
- Infections like HIV-AIDS, syphilis, etc.
- Taking certain medications or drugs
- Thyroid disorders
Risk factors for dementia
- Advanced age
- Genetic mutations and family history
- Physical inactivity
- Poor diet
- Low level of education
- High blood pressure
- Hypercholesterolemia (high levels of bad cholesterol)
- History of head trauma
- Trisomy 21
Dementia is often accompanied by depression and anxiety in the early stages of the disease as the person realizes the abilities they are losing. These symptoms transition over time to psychological and behavioural symptoms, such as wandering, agitation, aggression, screaming and refusal to cooperate.
Alzheimer's-type dementia is degenerative and progresses generally over 5 to 20 years.
In the early stage, sufferers have slight memory problems. They may have difficulty performing simple mathematical equations or following the steps in a recipe. Sometimes they experience language problems, such as using words inappropriately or having difficulty understanding others. The person could also have a poor awareness of time and get lost in places that they know well. This stage tends to go unnoticed because the cognitive function deteriorations described above are often seen as a normal progression in aging.
In the middle stage, the person begins to forget recent events and fails to retain new information. They can become disoriented and confused. It is at this stage that the person begins to have difficulty performing their daily tasks on their own. There is a decrease in the person’s ability to function. For example, they may need help bathing themself and getting dressed.
In the terminal stage, the person is dependent for all activities. They no longer recognize their relatives or familiar places and is no longer aware of time. In the end, the person is unable to move, and can no longer walk or eat.
In short, Alzheimer's disease affects a person’s memory and the social and intellectual abilities, but as well as their motor skills.
Reisberg Global Deterioration Scale
|Mild symptoms (recent memory loss, difficulty making decisions) with no measurable decline on neuropsychological tests.
|Mild symptoms with measurable decline on neuropsychological tests, but without significant interference with daily activities.
|Mild dementia (ability to drive a car if accompanied).
|Moderate dementia (clothing selection must be done by someone else; walking in familiar places only; someone else must manage personal finances).
|Severe dementia (must be bathed and dressed by another person; cannot be left alone).
|Very severe to terminal dementia (inability to walk safely; difficulty swallowing).
* Source: Reisberg et al., 1984
If you would like to learn more about Alzheimer's, your Familiprix-affiliated pharmacist can give you a free booklet on the subject. You can also read it online here or read our article on the subject.
Lewy body dementia
Like Alzheimer's, Lewy Body Disease gradually increases and symptoms are often not noticed early on. The progression is rapid. However, there are a lot more fluctuations in cognitive state, i.e. some days give the impression that the person's condition is improving, then the next day they are back to experiencing severe symptoms. There are also a lot of changes in attention and alertness.
The main symptoms are mood swings, behavioural disturbances and thought disturbances. Parkinson-like mobility disturbances are also seen, usually more than a year after the onset of other symptoms. One of the typical symptoms of Lewy body disease is very detailed and recurrent visual hallucinations.
As mentioned earlier, vascular dementia is often secondary to stroke. Patients therefore have residual symptoms such as difficulty speaking or walking, and paralysis. The symptoms associated with dementia, on the other hand, tend to be memory loss and fits of laughter or tears. Symptoms can vary depending on the area of the brain affected by the stroke.
Symptoms start earlier than with other types of dementia. In fact, they often appear between 50 and 60 years of age. It is mainly social skills and language that are affected. People are listless, uninhibited and have eccentric behaviours. The rate of speech is reduced and social relationships are difficult. The attack on the memory varies; usually, changes in behaviour are seen first. Then the person develops cognitive impairment and becomes dysfunctional, as seen in other types of dementia.
Diagnosis and treatment
The doctor’s diagnosis may include the following:
- Cognitive tests
- History of the disease in the patient’s relatives, or the patient themself if still possible
- Physical assessment
- Blood tests
- Medical imaging
The diagnosis is usually not certain. It is based on the symptoms, their order of appearance and the medical information collected. Sometimes it is only diagnosed after death, during an autopsy.
Certain drugs exist to slow down the disease and reduce its symptoms. They increase the transmission of information between neurons in the brain. On the other hand, their effectiveness is modest and depend upon the stage of the disease.
None of the dementias described above have a cure.
Despite the recurrence of genetic factors and family history in risk factors for different types of dementia, there are many ways you can reduce your risk of developing dementia:
- Quit smoking
- Consume alcohol in moderation
- Have a low-fat diet, rich in omega-3
- Avoid head injuries
- Exercise regularly
- Practice cognitive training and keep the brain active
- Control your cardiovascular risk factors: hypertension, diabetes and cholesterol
- Maintain or achieve a healthy weight
Even if the causes of Alzheimer's are unknown and probably multiple, the above factors have nonetheless been shown to be protective elements. In addition, they also reduce the risk of stroke and therefore vascular dementia.
In general, adopting good lifestyle habits, such as those that protect the heart and reduce the incidence of cancer, also decreases the risk of dementia. Add to that keeping your brain active, and voila!
Advice for relatives
Some signs of cognitive function impairment:
- Frequent memory loss that causes problems on a daily basis
- Regular loss of objects
- Difficulty with speaking, frequent forgetting or misuse of words
- Loss of awareness of time and space
- Loss of ability to make good judgement
- Loss of initiative, motivation; becomes apathetic
- Difficulty thinking in the abstract
- Difficulty doing everyday tasks, such as getting dressed or bathing, as well as tasks usually done by the person, such as cleaning or cooking (not caused by an apparent physical problem or any pain)
- Change in personality
- Change in behaviour or mood swings
If you live with or are a caregiver of someone with dementia:
- Take the person to the doctor
- Go with them when they drive, if they are still able, and if not, drive them yourself or find another person to accompany them
- Continue to take the person to social activities
- Write their name on the main objects in the home
- Create a routine
- Arrange your home so that it is safe and the environment is calm
- Name yourself when you approach the person
- Write down appointments, important events and phone numbers in a diary. Leave it accessible to the person
- If the person is at risk of wandering away, give them an identification sheet and contact details
Don't hesitate to ask for help if needed! There are support groups for family and loved ones. If the situation is too much for you to handle, a long-term care residence may be the best solution.
To find out more: Informal caregivers: take care of yourself and others