Written by Josh Horsman
Dementia is a progressive neurological condition which affects and impairs key functions of the brain like memory, judgement, behavior and mood. It is a condition typically associated with ageing, although Young-Onset Dementia is surprisingly common. But while the symptoms of Dementia are recognizable to most of us, there is a glaring lack of awareness about what causes Dementia and what can be done to reduce the risk of someone developing it.
To put it simply, Dementia results from damage to the nerve cells within the brain. The damaged cells struggle to communicate with each other and this causes the outward signs and symptoms that we all recognise and associate with the condition. But understanding the cause of this damage first requires an awareness of the different types of Dementia, as they all develop for slightly different reasons.
Neurodegeneration: (Alzheimer’s Disease, Lewy Body Dementia, Frontotemporal Dementia, Parkinson’s Disease)
The most common cause of Dementia, and that responsible for Alzheimer’s Disease, Lewy Body Dementia and some of the other most common types of Dementia, is a process called ‘Neurodegeneration’. In short, this refers to the decay and death of brain cells (called neurons). When the cells stop functioning well, and ultimately die, cognitive functions become more difficult for the brain to perform. This results in symptoms such as memory-loss, poor judgement and behavioral changes.
It is not known exactly what causes the neurons to die and it seems the process is slightly different for each form of Dementia, but in Alzheimer’s Disease it is thought to begin with abnormal deposits of proteins building up in and around the cells.
Cerebrovascular Causes: (Vascular Dementia)
Unlike some other forms of Dementia, the causes of Vascular Dementia (VD) are more apparent. VD is caused by problems with blood-flow to the brain causing it to become starved of the oxygen it needs to function effectively. This is usually the result of damage to the blood vessels in the brain, whereby they become blocked or damaged. Such damage is typically the result of other conditions, especially stroke, heart-disease or diabetes. When there is insufficient blood flow to the brain, its most starved sections cease to function well and this leads to the impaired thinking that results in the outward symptoms of VD.
Traumatic Brain Injury:
Another leading cause of Dementia is serious injury to the brain. A head injury which causes lasting cognitive impairment is called a Traumatic Brain Injury or TBI. TBI’s may be classed as mild, moderate or severe depending on the length of time the affected person remains unconscious, but even mild TBI’s can have long-term effects on brain function. TBI’s typically cause brain problems in their immediate aftermath including: memory-loss, learning difficulties, problems with speech and language and impaired coordination. However some TBI’s increase the risk of, or directly cause, Dementia in the long-term, with onset coming up to several years after the initial injury takes place.
Is Dementia Hereditary?
Many people who have known family members and loved-ones with Dementia fear that they may inherit the condition genetically. This is understandable given the toll that Dementia takes upon both those affected and those who care for them, but the fact is that that Dementia is very rarely a hereditary condition. As mentioned previously, both Vascular Dementia and TBI Dementias are typically caused by as a result of other factors, namely illnesses or injuries, meaning they are not the result of genetics. The most common type of Dementia - Alzheimer’s Disease (AD), is perhaps the most feared of all types of Dementia, but even this is extremely unlikely to be inherited. Whilst there are cases of AD being evident in family lines, statistics suggest that in 99% of cases, the condition is not inherited. These figures are slightly more significant for both Frontotemporal Dementia and Lewy Body Dementia, however neither of these are considered ‘genetic conditions’, rather there s simply an increased risk of developing the conditions if family members in previous generations have been affected.
Reducing Your Risk of Dementia
The causes of Dementia are complex and vary for each of the different types, however it is not thought that any form of Dementia is directly caused by lifestyle factors. That said, there is a growing body of evidence which suggests that by maintaining a healthy lifestyle in mid-life, it is possible to significantly reduce your risk of developing Dementia in later life. The renowned ‘FINGER’ scientific study concluded that to be most effective in preventing Dementia, such a healthy lifestyle should consist of four key elements: Regular exercise, a healthy diet, brain training and frequent social interaction.