Alzheimer’s disease

Alzheimer’s disease is the commonest cause of dementia. It constitutes about 50-75% of all cases of dementia (Alzheimer's Society, 2020).

Alzheimer’s disease is a progressive disorder that causes damage and death to bairn cells associated with memory and thinking. It has a gradual course and over time eventually has major effects on both cognition but also daily functioning.

Alzheimer’s disease is typically thought of as a disorder affecting mainly older people, but it can occur at earlier ages. If it begins before the age of 65, it is often referred to as young onset Alzheimer’s disease.

Signs and symptoms

• Memory impairment: gradually worsening memory is the commonest presenting symptom of Alzheimer’s disease. Memory for recent information and events is affected at an earlier stage. Memory impairment often presents as forgetfulness, repetition, loosing everyday items more often.
• Language difficulties including word finding difficulties, inability to express thoughts, impaired fluency of speech, impaired comprehension of spoken language.
• Difficulties in naming familiar people or objects.
• Impairment in executive functions for example planning and organising tasks, reasoning skills, following instructions involving multiple steps, multi-tasking.
• Difficulties in recognising familiar people or objects.
• Impairment in attention and orientation.
• Changes in personality or behaviour such as requiring prompts for routine activities, lack of appropriate emotion, change in food habit, mood instability, agitation or behavioural outburst.
• Change in mental state such as low mood, anxiety, delusion or hallucinations.
• Impairment in visuospatial abilities that is not being able to assess things in three dimensions for

The causes of Alzheimer’s disease is not fully understood. Risk factors for Alzheimer’s disease can be divided in to two categories:

Non-modifiable risk factors

1. Age is identified as the biggest risk factor for Alzheimer’s disease. After 65 years of age the risk of Alzheimer’s disease doubles after every five years. After age 85 the risk increases further affecting about one-third of all people over this age group (Alzheimer’s Association, 2022a ).
2. Female gender.
3. Positive family history. Strong genetic inheritance is more common in young onset Alzheimer’s disease than the late onset illness.

Potentially modifiable risk factors

• Low education
• Hearing impairment
• Hypertension
• Traumatic brain injury
• Alcohol excess
• Obesity
• Smoking
• Depression
• Social isolation
• Physical inactivity
• Diabetes
• Air pollution (Livingston et al, 2020)

 Public health approach targeting the potentially modifiable risk factors can play a significant role in reducing population risk of Alzheimer’s dementia in future.

Higher rates of dementia have been reported

Routine diagnostic process involves-

1. Clinical assessment that is detailed history from the individual and their family or carer and use of memory tests (which includes mini-Addenbrook’s cognitive examination and Addenbrook’s cognitive examination-III).
2. Brain scans such as CT or MRI .

Sometimes different types of brain scans such as flurodeoxyglucose positron emission tomography (FDG-PET), perfusion singe photon emission computed tomography (SPECT) are used to differentiate Alzheimer’s from other types of dementias where diagnosis is uncertain.

Specialist assessments such as neuropsychological assessment may be required if diagnosis of Alzheimer’s disease is not clear from history and neuroimaging.

Cerebrospinal fluid (CSF) analysis to detect level of abnormal proteins (biomarkers) such as tau and beta-amyloid has been added to National Institute for Health and Care Excellence (2018) guidelines for investigation of Alzheimer’s disease.

Interventions to alter modifiable risk factors such as physical and cognitive activities, glucose and metabolic regulation, stress and sleep to enhance brain health can be preventative in reducing the likelihood and severity of Alzheimer’s disease (Johnson et al 2018).

As with any other dementia the primary goal of management and treatment of people with Alzheimer’s disease is helping the individuals with dementia to live their lives as independent as possible in their own environment.

Treatment can be non-pharmacological or pharmacological treatment:

Non-pharmacological treatment

The following non-pharmacological aspects of care are crucial:

• Planning the future by providing information about LPA (lasting power of attorney), advance decision, advance statement.
• Maintaining safety and wellbeing in the home environment such as home-adjustments, handrails, dementia clock, medications delivered in blister pack, pendant alarm etc.
• Maintaining safety in driving and transport. This includes informing DVLA, car insurance company and not to drive until gets assessed either

Alzheimer’s disease is progressive and often contributes to the cause of people’s death.

So far, treatments seem only to be of temporary, symptomatic benefit and don’t affect the longer-term course of Alzheimer’s disease.

Nonetheless much can be done to support people with dementia and their families for example through information, pursuing good health, improving social contact and activities.

References

Alzheimer’s Association. Causes and risk factors for Alzheimer's disease. 2022a. (https://www.alz.org/alzheimers-dementia/what-is-alzheimers/causes-and-risk-factors) (accessed 21 November 2022)

Alzheimer’s Association. Aducanumab approved treatment of Alzheimer's disease. 2022b. (https://www.alz.org/alzheimers-dementia/treatments/aducanumab) (accessed 21 November 2022)

Alzheimer’s Society. Alzheimer's Society's views on demography. 2020.(https://www.alzheimers.org.uk/about-us/policy-and-influencing/what-we-think/demography) (accessed 21 November 2022)

Baber W, Chang CYM, Yates J, Dening T. The Experience of Apathy in Dementia: A Qualitative Study. Int J Environ Res Public Health. 2021;18(6):3325. https://doi.org/10.3390/ijerph18063325

Johnson SC, Koscik RL, Jonaitis EM et al. The Wisconsin Registry for Alzheimer's Prevention: A review of findings and current directions. Alzheimers Dement (Amst). 2017;10:130-142. https://doi.org/10.1016/j.dadm.2017.11.007

Livingston G, Huntley J, Sommerlad A et al. Dementia prevention, intervention, and care: 2020 report of the Lancet Commission. Lancet. 2020;396(10248):413-446. https://doi.org/10.1016/S0140-6736(20)30367-6

Meiland F, Innes A, Mountain G et al. Technologies to Support Community-Dwelling Persons With Dementia: A Position Paper on Issues Regarding Development, Usability, Effectiveness and Cost-Effectiveness, Deployment, and Ethics. JMIR Rehabil Assist Technol. 2017;4(1):e1. https://doi.org/10.2196/rehab.6376

National Institute for Health and Care Excellence. Dementia: assessment, management and support for people living with dementia and their carers NICE guideline [NG97].