Dementia

DEMENTIA OVERVIEW 

Dementia results from a variety of diseases and injuries that affect the brain. Dementia is a syndrome that can be caused by a number of diseases which over time destroy nerve cells and damage the brain, typically leading to deterioration in cognitive function (i.e. the ability to process thought) beyond what might be expected from the usual consequences of biological ageing.

TYPES OF DEMENTIA

Types of dementias that worsen and aren't reversible include:

1. Alzheimer's disease. This is the most common cause of dementia.
   
   Although not all causes of Alzheimer's disease are known, experts do know that a small percentage are related to changes in three genes. These gene changes can be passed down from parent to child. While several genes are probably involved in Alzheimer's disease, one important gene that increases risk is apolipoprotein E4 (APOE).
   
   People with Alzheimer's disease have plaques and tangles in their brains. Plaques are clumps of a protein called beta-amyloid. Tangles are fibrous masses made up of tau protein. It's thought that these clumps damage healthy brain cells and the fibers connecting them.
   
   
2. Vascular dementia.
   This type of dementia is caused by damage to the vessels that supply blood to the brain. Blood vessel problems can cause stroke or affect the brain in other ways, such as by damaging the fibers in the white matter of the brain.
   The most common symptoms of vascular dementia include problems with problem-solving, slowed thinking, and loss of focus and organization. These tend to be more noticeable than memory loss.
   
   
3. Lewy body dementia.
   Lewy bodies are balloonlike clumps of protein. They have been found in the brains of people with Lewy body dementia, Alzheimer's disease and Parkinson's disease. Lewy body dementia is one of the more common types of dementia.
   Common symptoms include acting out dreams in sleep and seeing things that aren't there, known as visual hallucinations. Symptoms also include problems with focus and attention. Other signs include uncoordinated or slow movement, tremors, and stiffness, known as parkinsonism.
   
   
4. Frontotemporal dementia. This is a group of diseases characterized by the breakdown of nerve cells and their connections in the frontal and temporal lobes of the brain. These areas are associated with personality, behavior and language. Common symptoms affect behavior, personality, thinking, judgment, language and movement.
   
   
5. Mixed dementia. Autopsy studies of the brains of people age 80 and older who had dementia indicate that many had a combination of several causes. People with mixed dementia can have Alzheimer's disease, vascular dementia and Lewy body dementia. Studies are ongoing to determine how having mixed dementia affects symptoms and treatments.

CAUSES

Dementia is caused by a variety of diseases that cause damage to brain cells. This damage interferes with the ability of brain cells to communicate with each other. When brain cells cannot communicate normally, thinking, behavior and feelings can be affected.

The brain has many distinct regions, each of which is responsible for different functions (for example, memory, judgment and movement). When cells in a particular region are damaged, that region cannot carry out its functions normally.

Sommon causes can be:

1. Depression.
2. Medication side effects.
3. Excess use of alcohol.
4. Thyroid problems.
5. Vitamin deficiencies.

SYMPTOMS

1. Cognitive changes
   Memory loss, which is usually noticed by someone else.
   Problems communicating or finding words.
   Trouble with visual and spatial abilities, such as getting lost while driving.
   Problems with reasoning or problem-solving.
   Trouble performing complex tasks.
   Trouble with planning and organizing.
   Poor coordination and control of movements.
   Confusion and disorientation.
   
   
2. Psychological changes
   Personality changes.
   Depression.
   Anxiety.
   Agitation.
   Inappropriate behavior.
   Being suspicious, known as paranoia.
   Seeing things that aren't there, known as hallucinations.

ASSOCIATED PROBLEMS

Dementia has physical, psychological, social and economic impacts, not only for people living with dementia, but also for their carers, families and society at large. There is often a lack of awareness and understanding of dementia, resulting in stigmatization and barriers to diagnosis and care.

Huntington's disease. Huntington's disease is caused by a genetic change. The disease causes certain nerve cells in the brain and spinal cord to waste away. Decline in thinking skills, known as cognitive skills. 

Traumatic brain injury (TBI). This condition is most often caused by repetitive head trauma. Boxers, football players or soldiers might develop TBI.

Dementia symptoms depend on the part of the brain that's injured. TBI can cause depression, explosiveness, memory loss and impaired speech. TBI also may cause slow movement, tremors and stiffness. Symptoms might not appear until years after the trauma.

Creutzfeldt-Jakob disease. This rare brain disorder usually occurs in people without known risk factors. This condition might be due to deposits of infectious proteins called prions. Symptoms of this fatal condition usually appear after age 60.

Creutzfeldt-Jakob disease usually has no known cause but it can be passed down from a parent. It also may be caused by exposure to diseased brain or nervous system tissue, such as from a cornea transplant.

Parkinson's disease. Many people with Parkinson's disease eventually develop dementia symptoms. When this happens, it's known as Parkinson's disease dementia.

FACTORS

1. Age (more common in those 65 or older)
2. High blood pressure (hypertension)
3. High blood sugar (diabetes)
4. Being overweight or obese
5. Smoking
6. Drinking too much alcohol
7. Being physically inactive
8. Being socially isolated
9. Depression.
10. Common changes in mood and behaviour include:

TREATMENTS

STATISTICS

Currently more than 55 million people have dementia worldwide, over 60% of whom live in low-and middle-income countries.

Every year, there are nearly 10 million new cases.

Alzheimer disease is the most common form of dementia and may contribute to 60–70% of cases.

Dementia is currently the seventh leading cause of death and one of the major causes of disability and dependency among older people globally.

In 2019, dementia cost economies globally 1.3 trillion US dollars, approximately 50% of these costs are attributable to care provided by informal carers (e.g. family members and close friends), who provide on average 5 hours of care and supervision per day.