Overview

Transient global amnesia (TGA) is an episodic memory disorder affecting the hippocampus of primarily middle-aged and older individuals. This sudden, temporary episode of memory loss can last up to 24 hours. The cause of TGA remains unclear, but episodes often follow a triggering event. The inability to form new memories can also be called anterograde amnesia.

One area of ongoing debate is the potential link between alcohol consumption and TGA, as the exact relationship between alcohol and TGA is uncertain. Does alcohol play a role in triggering these episodes, especially in those individuals who consume alcohol regularly or in large quantities?

This article will explore the impact of alcohol use on TGA and what implications this may have for individuals. Understanding this is vital for medical professionals and individuals experiencing these episodes, as it may provide insight into risk factors and prevention strategies. 

Common triggers of TGA

The following could trigger a memory loss episode:

• Physical exertion 
• Vascular issues
• Emotional or psychological stress 
• Acute pain 
• Water contact with extreme temperature change 
• Sexual Intercourse 

 Symptoms of TGA

• Anterograde Amnesia
• Headache
• Nausea
• Dizziness
• Chills or Hot flushes
• Sweating
• Trembling

Diagnosis and treatment of TGA

Medical intervention is needed to ensure that these episodes are not mistaken for other neurological issues or head trauma, like stroke, epilepsy or transient ischemic attack (TIA). Brain imaging methods, like MRI, are used to identify this. Stroke, epilepsy, and head trauma can be ruled out if scans show no evidence of this. In cases where the diagnosis is uncertain, it is important to perform cognitive assessments or EEG studies so that diagnosis is not confused with other serious conditions like TIA.

There is no specific treatment required as TGA episodes will resolve themselves within 24 hours. There is no medication specifically made for preventing or shortening episodes. However, showing support and reassurance to patients is ideal, as this could be distressing. Most patients with transient global amnesia will experience complete resolution of symptoms without any long-term impacts. TGA also has negligible mortality reported, although episodes can recur, making the prognosis highly favourable.

How does alcohol affect the brain?

Alcohol primarily affects the brain by disrupting the function of the hippocampus, which leads to impaired short-term memory. The main function of the hippocampus is to help with learning, memory, spatial navigation and verbal memory. As alcohol interferes with the brain's communication pathways, long-term heavy drinking can cause alterations in the neurons and even a reduction in the brain size.

Excessive alcohol intake can cause alcohol induced blackouts, which are different to TGA episodes. The alcohol induced blackouts will temporarily block the transfer of memories from short-term to long-term storage. Symptoms of alcohol overdose include mental confusion, difficulty remaining conscious, vomiting, dulled responses and slow heart rate. While these symptoms resemble those of TGA episodes, there are some differences in these blackouts.

Short-term alcohol use

Alcohol will initially cause blood vessels to expand as well as increase heart rate. Individuals will become more sociable and talkative. The more units consumed, cells in your nervous system are affected, making reaction times much slower, and vision will become affected. Coordination, decision making and judgment will become impaired. Individuals will likely experience symptoms of a ‘hangover’ like a headache, nausea and tiredness as their liver attempts to remove the alcohol from their body.

In extreme cases, alcohol poisoning can occur, which is usually when you drink faster than your body can filter out. This will stop the body from working properly and could be life-threatening. This will require medical attention.

Long-term alcohol use

Someone who consumes excessive alcohol regularly may have alcohol-related brain damage (ARBD). This can cause memory loss, confusion and difficulty concentrating. This can damage parts of the brain in many ways

Too much alcohol can be toxic to nerve cells and blood vessels, causing brain shrinkage and increased blood pressure. Cells begin to die and increase the risk of experiencing other health complications, like having a stroke.

Organs which are affected by long-term alcohol use are the heart, liver and pancreas. For example, alcohol can cause cirrhosis, a permanent condition. This will increase the risk of cancer and reduce life expectancy if alcohol consumption continues.

Blackouts: TGA vs alcohol

Alcohol induced blackouts tend to occur at blood alcohol concentrations higher than 0.16%. Individuals can experience a ‘fragmentary blackout’, which is usually characterised by spotty memories; however, some can also experience complete amnesia. This is a more severe form of blackouts, and memories do not form or recover.

Individuals with transient global amnesia will experience blackout-like episodes. Those affected will not be able to remember new memory content for longer than 30-180 seconds. This can be observed by individuals asking repetitive questions, but their cognitive functions will not be impaired.

Can alcohol consumption trigger TGA?

Some researchers have assumed that alcohol contributes to TGA. This is because alcohol can exacerbate vascular issues, which is a known trigger of TGA, as well as alcohol could lead to sleep deprivation and emotional distress which could also increase the likelihood of experiencing an episode

The exact cause of transient global amnesia is not fully understood, but some suggest that benign transient amnesia after substance ingestion could be caused by excessive alcohol consumption or use of recreational drugs. Alcohol may contribute to TGA by disrupting the functioning of the hippocampus. Many individuals who experience TGA have no history of alcohol use, suggesting other factors may be coming into play. Overall, there is no conclusive evidence proving that alcohol directly causes TGA. More research is needed to determine whether alcohol consumption increases the susceptibility to TGA.

FAQs

Can I prevent transient global amnesia?

No, currently there is no definitive way to prevent transient global amnesia (TGA), as the exact cause is unknown. By preventing potential triggers listed above and adopting a healthy lifestyle, you could minimise your risk of future occurrences.

How common is transient global amnesia?

Transient global amnesia is considered a rare syndrome that affects 3.4 to 10.4 out of every 100,000 people each year. However, this condition is more common in people above the age of 50. The incidence rate increased to approximately 23.5 to 32 out of every 100,000 people in that age group.

Are there any long-term impacts of TGA?

TGA usually has no long-term impacts; most people will recover within 24 hours and be able to form new memories once the episode ends. TGA is regarded as temporary and fully reversible. The risk of recurrence for TGA is approximately less than 5.8%, so not as common.

What is the difference between Transient Ischemic Attack (TIA) and Transient Global Amnesia (TGA)?

TIA is much more severe than TGA as it is a temporary disruption of the blood flow to the brain. Symptoms of this are weakness, numbness and speech problems. TGA episodes allow individuals to function normally while impacting memory only. TIA will impact various neurological functions, but patients with TGA will not be at increased risk of experiencing TIA.

Summary

Although alcohol is known to have significant effects on cognitive functions, scientific research does not completely prove that alcohol consumption triggers transient global amnesia (TGA). While some studies suggest a direct association with Alcohol and TGA, it remains unclear if alcohol plays a primary role in causing TGA. The causes of TGA remain uncertain, making it harder to find the exact cause of the risk factors. Individuals who have experienced an episode are strongly advised to maintain a healthy lifestyle. This includes weight management, smoking/alcohol avoidance and medication adherence. Further research is needed to clarify the potential relationship between alcohol and TGA.

Due to the limited understanding of the influence of alcohol on TGA, further research is required. These future studies should explore whether specific drinking patterns influence susceptibility to TGA. These could be used as potential preventative measures to improve management strategies.