31st January 2024

Dementia secondary to alcohol misuse

Background

There are several subtypes of dementia, characterised by different patterns of cognitive impairment, loss of learned skill and independent functioning. There is some evidence that heavy and sustained alcohol use can result in early-onset dementia presentations and is a potentially modifiable risk factor for dementia.

There are several proposed hypotheses as to the link between heavy alcohol use and dementia, which include the following:

1. Ethanol is metabolised to acetaldehyde – this substance is known to be neurotoxic.
2. As previously mentioned, thiamine deficiency secondary to heavy alcohol use can result in Wernicke’s encephalopathy and/or Korsakoff’s syndrome – for some chronic cognitive impairment persists despite treatment.
3. Heavy alcohol use can increase the risk of developing cardiovascular risk factors such as hypertension, which are themselves associated with an increased risk of developing vascular dementia.
4. Alcohol intoxication can cause falls with head injury or seizures, both of which have been raised as potential predisposing factors in alcohol-related dementia development.

Presentation

The symptoms of alcohol-related dementia are like symptoms seen in other dementia profiles but include problem-solving issues, cognitive impairment to varying degrees, gait disturbance and low mood/apathy.

Differential diagnoses

Other types of dementia would need to be considered as part of an initial workup. However, a thorough history, including past and present alcohol use, as well as standard first-line investigations for dementia diagnosis as per NICE guidance, e.g., CT head, would be recommended as part of investigation prior to deciding on a diagnosis of alcohol-related dementia.

Management 

It has been proposed that if alcohol consumption is reduced/abstained from and thiamine replacement given alongside other lifestyle measures such as good dietary intake etc, that alcohol-related dementia presentations can improve. Talking therapies such as cognitive behavioural therapy (CBT) and rehabilitation are also important factors in ensuring recovery can continue and progress and reduce the chance of relapse.

References

• Rehm J, Hasan OS, Black SE, Shield KD, Schwarzinger M. Alcohol use and dementia: A systematic scoping review. Alzheimer’s Research & Therapy. 2019;11(1).
• Alzheimer’s Society. Alcohol-related ‘dementia’ [Internet]. Alzheimer’s Society. 2021 [cited 2022Dec3]. Available from: https://www.alzheimers.org.uk/about-dementia/types-dementia/alcohol-related-dementia
• Stringer S, Church L, Keynejad R, Hurn J. Psychiatry P.R.N.: Principles, reality, next steps. Oxford: Oxford University Press; 2020.