What Causes Dementia?

The word ‘dementia’ is used to describe a set of symptoms that can include memory loss, difficulty problem-solving, reduced language skills, and behaviour changes. Dementia isn’t a disease; it’s an umbrella term for a set of symptoms caused by several different conditions, with Alzheimer’s disease being the most common.

Learn more about what dementia is and its most common causes in our helpful guide.

What is dementia?

Dementia is a progressive condition, meaning it slowly gets worse over time. Symptoms like memory loss, problems communicating or finding the right words and confusion gradually get worse until they substantially affect everyday life.

The most common symptoms of dementia include:

  • Memory loss
  • Communication and language difficulties
  • Problems with reasoning or problem-solving
  • Trouble performing complex tasks
  • Confusion and disorientation
  • Personality changes
  • Anxiety and depression

Dementia occurs when parts of the brain used for memory, reasoning or judgement become damaged.

It’s estimated that 60-80% of people living with dementia have Alzheimer’s disease, but there are many other types of dementia including vascular dementia, dementia with Lewy bodies, and frontotemporal dementia.

Causes of Alzheimer’s disease

Alzheimer’s disease is a brain condition that results in impaired thinking, memory loss and speech and language difficulties. Currently, more than 520,000 people in the UK are living with dementia caused by Alzheimer’s disease and this number is expected to rise, due to people living longer.

The brain is made up of millions of interconnected nerve cells called neurons. Alzheimer’s disease causes abnormal plaques and tangles to build up over time in the brain. These plaques and tangles disrupt the brain’s neurons from functioning and affect their ability to work together and communicate.

When the neurons of a person’s brain can no longer communicate as they once did due to Alzheimer’s disease, everyday activities like speaking, thinking and reasoning become increasingly difficult.

Causes of vascular dementia

Vascular dementia is the second most prevalent dementia. Its root cause lies in the insufficient blood flow to the brain, depriving it of the essential oxygen and nutrients required for optimal functioning. This inadequate blood flow primarily arises from stroke or a series of minor strokes referred to as transient ischaemic attacks (TIAs).

Although vascular dementia shares many symptoms with Alzheimer’s disease, it most commonly affects a person’s thinking skills such as the ability to plan, organise and concentrate. This is why the first symptoms of vascular dementia are often related to the inability to plan or make decisions, rather than the memory loss that characterises Alzheimer’s disease.

Causes of dementia with lewy bodies

Lewy body dementia (LBD) is a type of dementia that impacts both the brain and the nervous system, making it the third most prevalent form of dementia in the UK. This condition arises due to the formation of unusual spherical structures known as Lewy bodies, which emerge within nerve cells.

Gradually, these Lewy bodies contribute to the decline and eventual death of nerve cells in the brain. People with LBD experience most of the usual dementia symptoms along with more unique challenges with visual hallucinations, and difficulties in movement.

Causes of dementia with frontotemporal dementia

Frontotemporal dementia (FTD) is a type of dementia that leads to challenges related to behaviour and language. This condition impacts either one or both of the frontal and temporal lobes of the brain. Notably distinct from many other dementia types, FTD frequently usually emerges in individuals aged 45 to 65.

Frontotemporal dementia has many various subtypes, each with its own distinct symptoms dependent on the regions of the brain that are affected. Some of the most common symptoms include changes in personality and behaviour, language impairments, issues with memory, and feelings of disorientation.

Rare causes of dementia

Other causes of dementia include:

  • Huntington’s disease: Stemming from an affected gene, this brain disorder leads to nerve cell breakdown, impacting movement control, cognition, memory, and personality
  • Parkinson’s disease: In advanced stages, Parkinson’s can lead to dementia with issues with thinking, memory, hallucinations, depression, and speech
  • Creutzfeldt-Jakob disease: A rare brain infection caused by abnormal proteins (prions) causing nerve cell death, resulting in thinking, memory, communication problems, confusion and behaviour changes
  • Wernicke-Korsakoff syndrome: Linked to severe vitamin B1 deficiency, often from alcohol misuse, causing bleeding in memory-related brain areas. Symptoms include double vision, coordination loss, and memory difficulties
  • Traumatic brain injury: From repeated head blows (common in sports and accidents), dementia symptoms emerge later in life including: memory loss, mood changes, speech issues, and headaches

Reversible causes of dementia-like symptoms

Dementia-like symptoms are sometimes caused by something reversible like a hormone imbalance or medication interactions. This is why it is so important to have any symptoms properly assessed by a doctor.

Some reversible causes of dementia include:

  • Tumours
  • Subdural hematomas, blood clots beneath the outer covering of the brain
  • Normal-pressure hydrocephalus, a buildup of fluid in the brain
  • Metabolic disorders such as a vitamin B12 deficiency
  • Hypothyroidism
  • Hypoglycemia
  • Alcohol or substance use disorder

Diagnosing dementia

If you or a loved one are experiencing any symptoms of dementia, it’s important to speak to your GP or other healthcare professional. Many conditions mask the symptoms of dementia, so a qualified healthcare professional can help you arrive at a proper diagnosis so you can receive the support you need.

At Oxford Aunts we understand how upsetting it can be when a loved one receives a diagnosis of dementia or is living with memory loss that is progressing.

With live-in dementia care provided by Oxford Aunts, you can be assured of a high-quality care service provided by a trusted and established provider – a service that has provided peace of mind to many families, for many years.

Talk to us about your dementia care needs

Call our friendly and approachable team today to see how we can help you and your family.


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