Dementia is a collective term for the condition of a number of diseases, which are characterized by permanent impairment of mental functioning. Approx. 200 different diseases can cause dementia or cognitive disorders. Alzheimer’s disease is the most common cause of dementia. About 60% of all causes of dementia is Alzheimer’s disease.
Dementia is not a consequence of getting old. It is a myth that dementia is a natural consequence of getting old, but it is such that the risk of dementia increases with age. There are only a few diseases causing dementia that can be cured. However, several diseases can be treated to some extent, so it is important to get diagnosis.
The stages of dementia
Although dementia is often slowly developing, there is a tradition of dividing the process into three stages corresponding to three degrees of dementia. The division is purely descriptive, and in practice, it is difficult to distinguish precisely between the three phases.
Mild dementia
The cognitive impairment only causes slight impairment of functional ability in everyday life. Routine-based daily and leisure activities can still be carried out and enable a largely independent existence. Complex tasks such as using public transport or the Internet often cause problems.
Moderate dementia
The cognitive impairment leads to a significant impairment of functional ability. The person can no longer manage in everyday life without the help of e.g. a healthy spouse and/or professional support – ea. home help, day care centre, home nurse and food delivery. The person can rarely be alone.
Severe dementia
The cognitive impairment means that the patient is completely dependent on the help of others. Moving to a nursing home will often be necessary. Regular monitoring is required.
The relative distribution of mild, moderate and severe dementia varies with age. In the ‘younger’ age groups, there are relatively many people with mild dementia and in the older age groups a higher proportion of people with severe dementia are seen. The English Alzheimer’s Society has estimated that mild dementia across the age groups amounts to approx. 55% of all dementia cases, moderate dementia account for approx. 32% and severe dementia account for approx. 12-13%. These numbers should be comparable to other Western European countries.
Common symptoms of dementia.
Most people with dementia suffer from memory problems, but other mental skills are also affected. It can be:
• initiative and action
• the ability to remember words and names
• the ability to find a way (location)
• numeracy
• overview and problem solving
The persons with dementia can change, social skills, emotional life and personality can be affected. This means that it will be harder for the persons to overview the social interaction and often finds it difficult to show empathy. The person can also lose his/her situational awareness. We may all sometimes find that there is something we cannot remember but if it affects a person’s ability to cope with everyday life, there is reason to suspect some kind of dementia.
Categories of dementia
1. Neurodegenerative diseases.
Neurodegenerative diseases are diseases where a gradual, often slow breakdown of the brain and its functions occur. For example, Alzheimer’s disease, Frontotemporal dementia or Lewy Body Dementia.
2. Vascular Dementia.
Vascular Dementia is dementia caused by disturbances in the brain’s blood supply or blood vessel. The disturbances may be due to blood clots, bleeding or narrowing of the blood vessels of the brain.
3. Other diseases.
A number of other diseases with direct or indirect influence on brain function can cause cognitive impairment. For example, there may be metabolic disorders, chronic deficiency of B vitamins or poisoning conditions.
The distribution of the different categories of dementia in Denmark:
Reference: https://www.alzheimer.dk
The figure shows the distribution in Denmark of different diseases causing dementia. 62% has Alzheimer’s disease, 17% has vascular dementia, 10% a mix of Alzheimer and vascular dementia, 4 % has Lewy Body dementia, 2% has frontotemporal dementia, 2% has Parkinson’s with dementia and other diseases cause 3%
The disease process depends on the cause of the disease. Most dementia diseases are progressive disorders that cannot be cured. The course may vary from year to several decades.
Dementia diseases are generally not hereditary. In Alzheimer’s disease, only 2-3% of the cases are directly due to inheritance. The reason for the other cases of Alzheimer’s is more uncertain.
Frontotemporal dementia is the common name for a group of relatively rare diseases, which account for only 5-10% of the total number of dementia cases. Frontotemporal dementia is more commonly inherited, as up to 40% of the cases are genetically conditioned.
The possibility of treatment is different depending on which disease is the basic one. Counselling and practical assistance, care and relieving of relatives are important elements of the treatment. In addition, doctors since the 90s have been able to prescribe medications that temporarily dampen the symptoms of, for example, Alzheimer’s disease. In Vascular Dementia, which may be due to blood clots in the brain, the treatment aims to prevent the formation of more blood clots. Some of the diseases can be cured, e.g. metabolic disorders, depression, side effects or misuse of medicines. It is therefore important always to clarify what is the cause of the symptoms. Therefore, it is equally important to be diagnosed as early as possible.
Characteristics of Alzheimer’s dementia
Alzheimer’s dementia is by far the most common form of dementia. Typical symptoms are memory problems, especially short-term memory is affected and one has trouble finding the right words, especially nouns are hard to remember. Everyday life is affected because it becomes harder to overlook ordinary things like finding out the way, counting money and paying, etc. As the disease develops, changes in emotion, temperament and social engagement can occur. People who have been open and social are being retrenched and confined and the mood can fluctuate a lot.
The symptoms develop slowly and the person may think that he is just tired or stressed. Gradually, the symptoms become harder and the surroundings are beginning to notice that something is wrong. The person can no longer fit a job or make his everyday work. Therefore, help is needed and in the longer term, professional help will be needed.The course of illness lasts an average of 8 to 10 years
The cause of Alzheimer’s dementia is unknown. Nevertheless, researchers can describe some of the changes that occur in the brain. There is accumulation of harmful protein substances between both the brain cells (beta-amyloid plaques) and inside the brain cells themselves (Tau jointing). The disease also causes a lack of the signal drug acetylcholine, which the brain cells use to communicate between each other. Both kinds of protein deposits can be seen in other dementia diseases, so it is the combination and distribution in the brain that is special for Alzheimer’s disease. In the case of Alzheimer’s disease, the areas of the temporal lobe that control the memory are usually affected. Therefore, especially the memory is affected.
The estimate is that 2-3% of Alzheimer’s disease is inherited, and you distinguish between an early and a late debut.
It is typical for Alzheimer’s dementia that it develops after the age of 65; this type is not hereditary. But the other type which is inherited or due to mutations can affect already at the age of 40. The main risk factor for Alzheimer’s disease is high age, but living conditions and behaviours that increase the risk of cardiovascular disease are also important factors, for example high blood pressure, diabetes and smoking.
Hat’s story: living with Alzheimer’s disease
Vascular Dementia
Vascular Dementia is caused by blood clots in the blood vessels of the brain. The disease thus can occur in all parts of the brain. Blood clots that are formed in the heart as a result of irregular heartbeat (atrial fibrillation), or that break free from atherosclerosis of the carotid arteries, can be routed with the blood stream to one of the brain’s larger blood vessels where they can get stuck. As a result, a larger brain area is deprived of its blood supply and is destroyed (this is called an infarct). If the injury is sufficiently large or hit a critical area, it can cause dementia. If the patient has more blood clots in other blood vessels in the brain, the damage will become more widespread (multi-infarct dementia).
In other cases, the small, fine blood vessels that supply the central areas of the brain (the white matter) are gradually closed. Here, the occlusion is usually not due to blood clots, but changes in the wall of the blood vessels that thicken as a result of high blood pressure or diabetes.
Vascular dementia is the second largest group of dementia diseases. The symptoms are very different here as it depends on which areas in the brain are affected. There may be forgetfulness, difficulty in concentrating, language problems, and more. There may be hemiparesis and therefore difficulty walking, disturbed tactile sense or narrowing the field of vision. If the person is hit in the deep structures of the brain, he/she can become apathetic and the thinking gets slower, you get trouble concentrating when solving more complex tasks. Persons with vascular dementia often show depressive symptoms. One’s emotional expression can fluctuate a lot, one cannot control cry or laughter, and emotional responses can emerge in situations where one does not feel sorry or happy. Unlike, for example, Alzheimer’s disease or Lewy body dementia, vascular dementia is not a neurodegenerative disease and the condition is not necessarily progressive. The symptoms of vascular dementia vary, as both the number and size of the vascular lesions, as well as the location of these, affect the symptoms and the degree of dementia. In some cases, there have been one or more strokes (apoplexies) with sudden onset, half-sided paralysis or speech impairment prior to the development of dementia. In other cases, the changes in the brain gradually occur without the occurrence of stroke. The most common cause is blood clots in the brain.
Vascular dementia cannot be cured, but one can do much to prevent the disease from getting worse. This prevention may be that the doctor prescribes blood pressure regulating, blood thinning or cholesterol lowering medication just as any diabetes should be well treated.
The risk factors are almost the same as for cardiovascular diseases. Our lifestyle affects several of the risk factors. It is important to exercise, eat healthy and avoid smoking because it both reduces the risk of cardiovascular disease and vascular dementia. If you have diabetes or high blood pressure, it is crucial to have treatment.
Vascular Dementia is not inherently in itself. Some of the risk factors for vascular dementia are partially hereditary, but are highly influenced by lifestyle.
Olive’s story: living with vascular dementia
Lewy Body Dementia
Lewy Body dementia is caused by the accumulation of a protein in the brain stem and therefore affects motor and movement. Lewy bodies are accumulations of a protein inside nerve cells deep down in an area of the brain called the brain stem that helps activate our movements. These Lewy bodies have been found in Parkinson’s disease patients, which in themselves cause slow, rigid movements, shaking of the hands, diminished mimicry, monotonous speech and tripping, bending gait. In Lewy Body dementia, the same Lewy bodies are found deep in the brain, in large parts of the brain – and also in areas that perform intellectual functions. For Parkinson’s disease, therefore, for many years, only movement disorders are seen, while at Lewy Body dementia you see a combination of movement disorders and dementia. Why, in some cases, Lewy bodies adhere to the lower central parts of the brain, and why they sometimes are spread to the entire brain, is not known. We know that the Lewy bodies are made up of a protein – alpha-synuclein – but why it accumulates in the cells and why these are destroyed is unknown.
Lewy body dementia is a neurodegenerative dementia disease that, in addition to dementia, also can cause movement disorders resembling the symptoms of Parkinson’s disease, as well as visual hallucinations and alternating attention. There may be shorter or longer episodes where the person seems distant, unclear or confused, but the condition may change from day to day and from hour to hour. The person may seem dull, indifferent, tired or numb, stare out into the air for longer periods and sleep more than usual during the day.
The person’s ability to plan, overview and orientate is influenced. Lewy Body dementia also means that the affected person tends to see visions during periods. The visions are usually quite lively, detailed and natural, e.g. in the form of people or animals that are present in the room without saying anything. The visual hallucinations do not necessarily seem scary. Three out of four patients get worse in walking and developing slow and rigid movements. The agitation disturbances resemble the symptoms of Parkinson’s disease. The fine motor control also gets worse, the speech becomes lower and slower, and there is less mimic. Lively nightmares and troubled movements disturb some patients sleep. Sleep disorders may develop several years before the other symptoms and occur frequently.
Lewy Body dementia is the third or fourth most common form of dementia. Lewy Body dementia can even be difficult for specialist physicians to distinguish from Alzheimer’s disease and Parkinson’s disease, which contributes to the uncertainty about how frequently the disease occurs.
Lewy Body dementia is a slow progressive brain disease that specifically affects older people. Hereditary forms of this disease have not yet been found. The greatest risk factor for the disease is age. There is no cure for Lewy body dementia, but medicine can temporarily dampen the dementia symptoms. It develops slowly and gradually, and often begins with changes in awareness or state of consciousness. The average debut age is around 75 years, which is about the same as for dementia of Parkinson’s disease. Lewy Body dementia is not described earlier than about 50 years old. There are no known risk factors for Lewy Body dementia beyond age. The disease is more frequent in men than in women.
Themiya’s story: living with dementia with Lewy bodies
Frontotemporal Dementia
Frontotemporal Dementia is not a single but many different diseases, each with its own distinctive characteristics. Common to the diseases is that they all start at the front of the brain and therefore alone cause the same kind of symptoms.
Almost half of patients with frontotemporal dementia have accumulation of tau protein in the nerve cells, which causes collapse in the nerve cells’ internal environment, just as in Alzheimer’s disease. Although the disease may be similar to Alzheimer’s at this point, it is different in that no beta-amyloid plaques are formed and the disease begins at the front of the brain’s frontal and temporal lobes. Frontotemporal dementia is often abbreviated FTD. Frontotemporal dementia manifests itself in the form of gradually increasing changes in personality, behaviour and / or language and differs from Alzheimer’s disease because learning and memory may still be intact in the process of the disease. However, frontotemporal dementia means that inhibitions of impulses and situational judgment perceive or disappear and the patient exhibits impulsive and uncontrolled behaviour and indifference to social norms. For example, the person may tend to eat or drink too much. The symptoms may look like certain psychiatric diseases, and frontotemporal dementia can therefore be difficult to diagnose. For example, at the beginning of the process of the illness, the doctor may think that it is a crisis action or a mania.
The cause of frontotemporal dementia is unknown, but 40% of the cases are hereditary. Frontotemporal dementia is associated with several different brain disease processes. Frontotemporal dementia cannot be cured and there are no drugs that slow down the disease. Nevertheless, it is very important that the person with dementia and family members get the right advice and support early. Disorders of behaviour and psychiatric symptoms are primarily dealt with by a specialized social education effort and by adapting the housing and environment in which the person lives.
Frontotemporal dementia often debuts earlier than other dementia diseases, typically between 55 and 65 years old, but it can also happen much earlier. The average survival time is from six to eight years. However, some have lived with the disease for up to 2 decades.
Frontotemporal dementia (FTD)
Video 1 Video 2 Video 3 Video 4
Characteristics of other diseases.
There are a number of diseases that contribute to dementia. Here, we will just mention a few since they do not affect as many people as the four above mentioned types.
- Alcohol-related dementia: Dementia caused by alcohol abuse does not constitute a well-defined disease state. It is uncertain whether it is alcohol itself that has a lasting harmful effect on the brain or whether the harm is caused by, the unhealthy lifestyle often associated with alcohol abuse.
- Huntington’s disease is a pronounced hereditary disease. With Huntington’s Disease, there is often a mixture of neurological and psychiatric symptoms and often dementia in the late stages. Symptoms may vary from person to person, but there are usually different degrees of involuntary chorea, uncertain gait and possibly more twisting movements (dystonia). Dementia is not seen in everyone. It develops slowly and only later in the process. In addition, delusions and depression may occur. In Denmark, there are around 300-400 patients with Huntington’s Disease.
- Disseminated sclerosis is a disease in which the body makes an inflammation reaction (inflammation) that destroys the isolation around the nerve threads. Disseminated sclerosis can develop dementia. There are also other rare inflammatory diseases that can affect the brain and give dementia.
- Certain heavy metal poisons, including lead and mercury, and prolonged exposure to organic solvents can cause memory and concentration weakness as well as dementia.
- Metabolism. These diseases are rare causes of dementia. There are different types of body metabolism processes that can affect the brain, so it causes dementia symptoms.
