What is Alcohol Dementia?
Alcohol dementia refers to an impairment of cognitive ability and personality changes as a result of alcohol misuse or chronic alcohol abuse and is referred to as alcohol-related psychosis or commonly as alcoholic psychosis. The presentation may also be due to Wernicke-Korsakoff syndrome which is a consequence of thiamine deficiency as a result of a malabsorption syndrome associated with long term alcohol use.
Alcoholic dementia or psychosis may closely resemble other disorders like schizophrenia or Alzheimer’s disease but unlike these two conditions, it will resolve in most cases once alcohol use is discontinued. However, in cases of chronic alcohol abuse over prolonged periods of time, alcoholic psychosis may be irreversible but in these instances the presentation may be related to Wernicke-Korsakoff syndrome.
Causes of Alcohol Dementia
The condition is more often seen in long term drinkers who have abused alcohol for many years. The development of alcohol dementia depends on a number of factors. It does not depend on the existence of any underlying psychiatric disorder or the age of the person. Instead the risk of developing alcohol dementia depends on the following factors :
- Frequency and Quantity
- Consuming alcohol frequently or on a daily basis as is seen with severe alcoholism.
- Consuming large amounts of alcohol (greater than the recommended daily allowance for adult males and adult females).
- Age of Commencing Frequent Alcohol Consumption
- Consuming alcohol from an early age.
- Duration of Alcohol Consumption
- Consuming alcohol (‘heavy drinking’) or chronic alcoholism (alcohol use affecting daily functioning with a craving for alcohol) for many years.
- Prenatal Alcohol Exposure
- Mother consumed alcohol while pregnant despite the absence of fetal alcohol syndrome (FAS).
There may be other contributing factors like genetic variables, other substance abuse (narcotics), underlying psychiatric disorders, nutritional deficiencies and general health status.
Alcohol dementia is not as clearly understood as Wernicke-Korsakoff syndrome. It has to be excluded from psychological changes seen in alcohol withdrawal and psychotic disorders.
Organic brain lesions may or may not be present with alcohol dementia although this could be ascribed to other underlying neurodegenerative disorders that may be missed. Wernicke-Korsakoff syndrome is better understood as it stems from a thiamine deficiency which results in neurodegenerative changes. A rare consequence of chronic alcoholism is demyelination of the corpus callosum known as Marchiafava-Bignami disease.
Alcohol consumption causes an increased secretion of certain neurotransmitters like dopamine. In alcohol dementia, the levels of dopamine due to alcohol consumption may cause excessive activity of certain parts of the brain, like the limbic system, which plays an integral role in a number of functions including emotions, memory and perception. These systems do not exist in isolation and play varying roles in other brain functions which would explain the signs and symptoms of alcohol dementia.
Signs and Symptoms
The presentation may not always be clearly reported by the patient due to reluctance in admitting that their alcohol use has reached a stage where it is affecting daily functioning. Family members and close friends may first take note of personality changes in response to excessive alcohol consumption or following bouts of alcohol binges. Patients with alcohol dementia often do not recall events during intoxication.
- Impaired memory
- Personality changes – ranging from depressed and withdrawn to excited and irritable.
- Poor judgement
- Difficulty making decisions
- Lack of insight
Alcohol-related psychosis is usually seen when there is :
- Excessive alcohol consumption
- During alcohol withdrawal
- Short periods of time after a bout of excessive consumption
Another unusual presentation is when a small amount of alcohol results in intoxication (drunkeness) leading to the signs and symptoms above. This is known as alcohol idiosyncratic intoxication. Individual tolerance to alcohol is always a factor but with alcohol idiosyncratic intoxication, the amount of alcohol required to trigger psychosis is significantly less than the patient’s reported tolerance. Sometimes one or two alcoholic drinks is sufficient to trigger the onset.