Dementia

We all experience moments of forgetfulness. Occasionally misplacing our keys or forgetting why we walked into a room is completely normal and happens to all of us. However, it can be a cause for concern if we experience consistent memory loss and confusion as this could indicate a greater problem, dementia.

Understanding this progressive brain disorder and recognising early signs means you can slow down dementia progression, manage symptoms and improve your or your loved one’s quality of life with the right treatment. 

What is Dementia?

Dementia is the term used to describe the gradual loss of cognitive function that affects a person’s ability to perform daily tasks. It can affect day-to-day living and functions, such as memory, thinking, reasoning and even behaviour.

It is important to note that dementia is not a specific disease but rather a syndrome that can be caused by other underlying  conditions [1].

Signs and symptoms of dementia

Most associate memory loss as an early sign of dementia, however memory loss does not always imply the start of dementia. As we age, it is normal to experience memory loss from time to time as some neurons in our brain naturally die off. 

Memory loss in dementia is much more severe and disabling, and can present danger to the person experiencing dementia symptoms.

Common symptoms of dementia include changes in:

• Memory – memory loss, forgetting names, getting lost in familiar places
  
• Cognitive ability – impaired reasoning, judgement, problem-solving skills, confusion
  
• Speech – difficulty in communication, not understanding what is being said/read
  
• Coordination – poor control of movements, problem with balance
  
• Mood – agitation, depression, anxiety, paranoia
  
• Behaviour – impulsiveness, lack of inhibitions, personality changes
  
• Poor judgement and decision making — struggling to make sound decisions, socially, financially and in personal matters
  
• Changes in sleep patterns — waking up more often during the night and napping more often in the day
  
• Hallucinations – visual hallucinations, seeing flashing lights or things that are not there

Each person suffering from dementia may be affected differently and, hence, can present symptoms differently.

What causes Dementia?

Dementia  can manifest due to damage or loss of connections of the neurons in the brain. This can be caused by a variety of factors. The most common cause of dementia in elderly patients is Alzheimer’s disease.

The causes of dementia can also be broadly classified based on the type of dementia experienced. Some types of dementia are caused by an accumulation of protein plaques and tangles in the brain, which causes neuron degeneration and inflammation [2].

Types of Dementia

Primary Dementia

Dementia that is the main problem and not caused by another disease, such as:

• Alzheimer’s disease — Alzheimer’s disease is the most common dementia causing disease in elderly patients. Alzheimer’s disease was reported in 5 – 6% of patients aged 65 and above and up to 30% in patients over 85.

The pathological hallmarks of Alzheimer’s are the accumulation of beta-amyloid plaques and neurofibrillary tangles of p-tau proteins, which gradually results in the patient’s cognitive decline [1, 2]. Early symptoms include forgetfulness, irritability, and apathy.

• Lewy body dementia — Lewy bodies are abnormal protein deposits in the brain. These Lewy bodies contribute to a hypoxia and reduced blood flow to the brain, causing damage to the neurons [2]. Lewy bodies also appear in patients with Parkinson’s disease and other neurological conditions [3].

Common symptoms of Lewy body dementia are lapses in focus and attention, visual hallucinations, and changes in sleep pattern.

• Vascular dementia — Neuronal damage in vascular dementia is thought to be caused by reduced blood flow to and hypoxia in the brain. Different causes that lead to vascular dementia include atherosclerosis, ischaemia, small vessel diseases, and bleeding in the brain [2]. Several factors can increase the risk of these incidences including high blood pressure, high cholesterol levels, and diabetes.
  
• Frontotemporal dementia – Frontotemporal dementias are caused by neurodegeneration of the frontal and temporal lobes of the brain. Patients with this type of dementia often exhibit changes in personality or behaviour, as well as trouble with speech or language such as having difficulty finding words.

• Mixed dementia – mixed dementia is a combination of two or more dementia, such as Alzheimer’s disease and vascular dementia. Mixed dementia is more prevalent in patients over 80 years of age. Diagnosis may be more challenging as the symptoms can overlap. Furthermore, the rate of cognitive decline may be more rapid compared to patients with only one type of dementia.

Secondary Dementia

Dementia caused by external factors or an underlying condition that causes cognitive decline, such as:

• Huntington’s disease — Huntington’s disease is a genetic neurodegenerative disease that causes dementia. This disease also has an early onset with patients as young as 30 – 40 beginning to show symptoms. Symptoms of Huntington’s include gradual decline in motor and cognitive skills accompanied by psychiatric problems.

The cause of this disease is described to be a mutation on the CAG repeats in the gene that codes for Huntington protein [4].

• Parkinson’s disease — Many patients suffering from Parkinson’s disease develop dementia as the disease progresses. Dementia in Parkinson’s also presents similar neuropathological characteristics as Lewy body dementia [1, 5].
  
• Traumatic brain injuries — Experiencing repeated head trauma can lead to neuronal damage, which is the premise of developing dementia later in life. Moderate to severe traumatic brain injuries can increase the risk of developing dementia between 2- to 4-fold [6]. These are commonly observed in boxers, wrestlers, football players, soldiers, and people who were involved in a vehicle accident.

The causes and symptoms of dementia in traumatic brain injuries depend on the part of the brain that was injured.

• Creutzfeldt-Jakob disease — Creutzfeldt-Jakob disease is an extremely rare neurodegenerative disease caused by an accumulation of misfolded proteins called prions. Transmission of this disease is very rare and usually occurs through exposure of central nervous system tissues, the food chain, or unsterile neurosurgical tools [7].

Reversible Dementia 

Dementia that can be improved or, in some cases, fully reversed once the underlying cause is effectively treated, such as:

• Infections or immune disorders — Some infections or immune disorders can cause cognitive disturbances. Infections from Lyme disease and SARS-CoV-2 can cause “brain fog”, while immune disorders such as AIDS or multiple sclerosis can cause dementia symptoms [8].
  
• Vitamin deficiency — Severe thiamine (vitamin B1) deficiency can lead to Wernicke encephalopathy, showing dementia symptoms such as memory disorders [1]. This is usually observed in chronic alcoholics or those with severe malnourishment. Wernicke encephalopathy can be treated with intravenous thiamine.

Patients with deficiencies in vitamin D, folic acid, niacin (vitamin B3) can also present dementia symptoms [1].

• Metabolic or endocrine disorders — Patients with hypothyroidism, hyperthyroidism, low blood sugar, Cushing’s disease, liver diseases, congestive heart failure, and severe obstructive sleep apnea can experience dementia-like symptoms [1].
  
• Medication – Certain medications such as antidepressants, cyclobenzaprine, and oxybutynin can also lead to the development of dementia symptoms. Sometimes interactions between different types of medication may also cause dementia-like symptoms as well. Consult your doctor if you are taking medication and are experiencing dementia symptoms.
  
• Normal-pressure hydrocephalus (NPH) – NPH happens when there is pressure buildup from cerebrospinal fluid (CSF) in the spaces of the brain, called ventricles. This can injure the brain and cause dementia symptoms, common symptoms are problems with balance, memory loss, difficulty focusing, and poor bladder control.

To get treated for NPH, your doctor will drain the excess CSF to regulate the pressure via a shunt surgery [9].

• Subdural haematoma — Bleeding between the surface of the brain and the layer covering the brain can cause dementia symptoms as well.
  
• Brain tumours — Brain tumours can also lead to dementia, although this is rare.

Who is at risk of dementia?

Although dementia is usually associated with old age, there are other risk factors for dementia, such as:

• Genetic predisposition — Patients with a family history of dementia are more likely to develop dementia.
• Down syndrome — People with Down syndrome are at a higher genetic risk of developing Alzheimer’s disease [10], which is the most common cause of dementia. Down syndrome is characterised by an extra copy of chromosome 21, which contains the gene for amyloid precursor protein (APP). Consequently, increased expression of APP can lead to the development of amyloid plaques, a hallmark of Alzheimer’s disease [10].
• Brain injury — Brain injuries, especially repeated traumas can increase the risk of developing dementia.
• Gender — Women are more likely to be affected by dementia compared to men.
• Cardiovascular risk factors — Obesity, high blood pressure, and high cholesterol increases the risk of developing dementia. As risk of atherosclerosis increases, so does the risk of developing dementia.
• Lifestyle factors, such as:

o   Alcohol and tobacco use – Excessive alcohol intake can cause changes in the brain. Studies reported that heavy drinkers are more likely to develop dementia, especially early onset dementia.
o   Exercise – Staying active and doing regular exercises can reduce the risk of dementia.
o   Diet – A diet rich in fresh fruits and vegetables, and fish can lower the risk of dementia.

Although some risk factors of dementia are non-modifiable, maintaining a healthy lifestyle can greatly reduce the risk of developing dementia, or delay the onset.

Stages of dementia

Dementia can be multifactorial, hence there may not be a clear definitive method to grade dementia. However, as Alzheimer’s disease is most common in dementia patients, the Alzheimer’s Association ranks the different stages of dementia based on the severity of cognitive decline, the symptoms in these Alzheimer’s disease stages are also common in many types of dementia:

• Early-stage Alzheimer’s disease (mild)

o   The most common symptom is memory loss – trouble remembering names, misplacing items, forgetting what was just said or read

o   Problems with language – difficulty finding a word

o   Difficulty being organised or completing tasks

• Middle-stage Alzheimer’s disease (moderate)

o   Increased memory loss – not remembering events or personal detail (phone number, address, important events in your life)

o   Confusion – includes wandering, getting lost, getting confused by current events, current year or season

o   Behavioural changes – paranoia, delusions, doing compulsive actions

o   Changes in sleep pattern

o   Problems with bowel or bladder control

• Late-stage Alzheimer’s disease (severe)

o   Trouble communicating – not being able to hold conversations

o   Trouble walking

o   Trouble swallowing – this may lead to pneumonia

o   Requiring constant care and assistance

As dementia progresses, the body’s function declines with the decline of brain function. Each patient with dementia may experience different rates of disease progression, hence there may not be a definite timeline on life expectancy, some patients with Alzheimer’s dementia can live up to 20 years.

How is Dementia diagnosed?

If you suspect you or a loved one may suffer from dementia, a visit to a neurologist is highly recommended.

During your visit, your doctor will review your medical history, as well as family history of dementia to determine whether it is hereditary. Understanding your symptoms can also aid the doctor with your diagnosis. These may include questions about:

• The symptoms you experience
• When the symptoms started
• How frequent they occur
• How it interferes with your life
• The severity of symptoms
• Whether you are taking any medications

Physical evaluation and input from family members or loved ones will also be important to further assist the neurologist in your diagnosis [11].

Next, your doctor will perform a number of tests for a comprehensive diagnosis, such as:

• Neurocognitive tests – These tests will determine your cognitive ability such as problem-solving skills, memory, judgement, reasoning, and language.
  
• Laboratory tests – Laboratory tests may be ordered by your neurologist to rule out possible underlying conditions, such as vitamin deficiencies, hypo/hyperthyroidism, or impaired liver function, that may cause the symptoms of dementia.
  
• Imaging tests – Imaging tests are useful for your doctor to identify abnormalities in the brain structure.

o   Computed tomography (CT) and magnetic resonance imaging (MRI) (link to service page) – These methods of neuroimaging are used to identify the presence of fluid buildup, bleeding, tumour, or evidence of stroke in the brain.

o   Positron emission tomography (PET) scans – PET scans can detect molecular abnormalities, such as amyloid plaques or tau protein tangles in the brain. This can also be accompanied with CSF analysis for biomarker detection [11].

• Psychiatric evaluation – Psychiatric evaluation by a mental health professional can determine whether mood disorders such as depression or anxiety can contribute to your dementia-like symptoms.

Can dementia be cured?

As mentioned earlier, dementia is not a condition as much as it is a syndrome. Some cases of secondary dementia can be reversed when treated early enough. That said, types of primary dementia cannot be cured and are progressive, which means it may get worse over time as brain cells continue to degenerate.

Thankfully, there are treatments that can help manage symptoms and slow dementia progression. 

Non-degenerative, reversible dementias can be reversed when given the right treatment. Some of these include:

• Metabolic or endocrine disorders — Hypothyroidism, hyperthyroidism, hypoglycaemia, vitamin deficiencies
  
• Use of medication — Medication that can cause dementia-like symptoms, such as antidepressants
  
• Depression — Long term or severe depression can cause pseudodementia, which are symptoms that mimic those of dementia.
  
• Brain tumours – Removal of the tumour can alleviate the symptoms
  
• Normal pressure hydrocephalus – Release of pressure from excessive CSF can reverse the symptoms of dementia

Dementia Treatments

• Medication — Your neurologist may prescribe medication to treat dementia. These medications are typically prescribed to Alzheimer’s patients to improve their impaired cognitive ability.

o   Donepezil, rivastigmine, galantamine – These are cholinesterase inhibitors, which work by inhibiting the enzymes that break down the neurotransmitter acetylcholine. This allows the connections between the neurons to last longer.

o   Memantine – Memantine inhibits the effects of glutamate activation of NMDA receptors. Overactivation of NMDA receptors by glutamate can damage the neurons, hence memantine protects the neurons from further damage.

o   Aducanumab – Aducanumab is an antibody that targets amyloid plaques, hence reducing the plaques in the brain.

o   Other medication – Your doctor may prescribe you other types of medication to alleviate symptoms such as depression, sleep problems, hallucination, or irritability.

• Therapy — Some forms of therapy can aid reducing cognitive decline in dementia patients.

o   Cognitive stimulation therapy — This is commonly used for cognitive stimulation in dementia patients, and was shown to improve cognition, mood, and quality of life [12].

o   Speech therapy — Speech therapy can help improve or maintain language skills in dementia patients who face problems with communication and language abilities.

o   Psychotherapy — This includes various types of therapy such as cognitive behavioural therapy, which can help patients cope with the emotional and psychological impacts of dementia.

• Lifestyle adjustments – Certain lifestyle adjustments may be necessary to improve quality of life. Depending on the severity of the cognitive decline, certain measures can be taken such as reducing clutter in homes, hiding objects that threaten safety (such as car keys), or carrying a tag or card with identifying information.

Living with dementia

Living with dementia isn’t easy, and finding out about your dementia diagnosis can be difficult news. Some forms of dementia cannot be reversed and will continue to progress. Treatments such as medication and therapy can slow down the progression, your neurologist can advise you on how to further improve your quality of life.

Several lifestyle improvements may be necessary to ease your daily life while suffering from dementia:

• Communication – Speaking slowly in simple sentences and using hand gestures can improve communication when struggling with language or conveying meaning
  
• Exercise – Regular exercise can improve balance and coordination, it can also slow down cognitive decline and reduce symptoms of depression
  
• Social activities – Engaging in social activities allows you to receive mental stimulation, while also improving mood
  
• Journaling – Keeping a journal and logging your thoughts and feelings can help with recall and memory
  
• Planning – Plan ahead for the future for your loved ones, this may include future care options, legal, and financial issues.

Summary

Living with dementia or watching a loved one go through it can be difficult. Although in most cases there is no definite cure, there are treatments available that can help manage symptoms and slow its progression, ultimately improving quality of life. 

All you need is the right care and support. Schedule a consultation with us today for a comprehensive diagnosis and a personalised treatment plan. 

References

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6.      Shively S, Scher AI, Perl DP, Diaz-Arrastia R. Dementia resulting from traumatic brain injury: what is the pathology? Arch Neurol. 2012 Oct;69(10):1245-51. doi: 10.1001/archneurol.2011.3747. PMID: 22776913; PMCID: PMC3716376.

7.      Vacca VM Jr. CJD: Understanding Creutzfeldt-Jakob disease. Nursing. 2016 Mar;46(3):36-42; quiz 42-3. doi: 10.1097/01.NURSE.0000480598.84274.0f. PMID: 26840797.

8.      Eggers C, Arendt G, Hahn K, Husstedt IW, Maschke M, Neuen-Jacob E, Obermann M, Rosenkranz T, Schielke E, Straube E; German Association of Neuro-AIDS und Neuro-Infectiology (DGNANI). HIV-1-associated neurocognitive disorder: epidemiology, pathogenesis, diagnosis, and treatment. J Neurol. 2017 Aug;264(8):1715-1727. doi: 10.1007/s00415-017-8503-2. Epub 2017 May 31. PMID: 28567537; PMCID: PMC5533849.

9.      Williams MA, Malm J. Diagnosis and Treatment of Idiopathic Normal Pressure Hydrocephalus. Continuum (Minneap Minn). 2016 Apr;22(2 Dementia):579-99. doi: 10.1212/CON.0000000000000305. PMID: 27042909; PMCID: PMC5390935.

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