What is Korsakoff Syndrome?
Korsakoff syndrome is a long-lasting brain disorder generally accepted to be caused by a deficiency of vitamin B1, or thiamine. This deficiency can damage multiple parts of the brain, leading to memory loss and confusion. Although the syndrome is most commonly associated with prolonged alcohol abuse, it can result from any condition that causes a lack of thiamine. It is often discussed alongside Wernicke encephalopathy, an acute and usually reversible brain disorder that often appears along with Korsakoff syndrome.
Both Korsakoff syndrome and Wernicke encephalopathy are sometimes encountered together, especially in long-term alcoholics. When they occur together, they are referred to as Wernicke-Korsakoff syndrome. This article uses ‘Wernicke-Korsakoff syndrome’ when discussing how to diagnose and treat a patient because the two conditions often overlap.
What Causes Korsakoff Syndrome?
Chronic thiamine deficiency, or a long-term lack of vitamin B1 in the body, can cause Wernicke’s encephalopathy. This condition affects the brain and nerves, and if it’s not treated, it can develop into Korsakoff syndrome. The most common cause of Korsakoff syndrome is chronic alcohol abuse.
Alcohol can interfere with the body in a couple of ways. It can prevent the gastrointestinal tract, which includes the stomach and intestines, from properly absorbing thiamine. Alcohol can also interfere with the liver’s ability to store this vitamin. Additionally, people who drink a lot of alcohol often don’t eat properly, which can lead to a further lack of thiamine.
Aside from alcohol abuse, there are other causes of Korsakoff syndrome. These include eating disorders, chronic vomiting (which can even happen during pregnancy), mental health disorders, chemotherapy, and cancer.
Risk Factors and Frequency for Korsakoff Syndrome
Wernicke-Korsakoff syndrome is a condition that affects between 0 and 2% of people around the world. It’s especially common in specific groups – the homeless, elderly, and psychiatric patients. However, it’s worth noting that because the condition is often not diagnosed properly, and doctors don’t always agree on how to identify it, we don’t have exact numbers on how many people it affects.
Signs and Symptoms of Korsakoff Syndrome
Wernicke encephalopathy and Korsakoff syndrome are interlinked conditions caused by a lack of thiamine (vitamin B1), hence it’s vital to check for them simultaneously. Wernicke encephalopathy mainly shows up with symptoms such as confusion, eye coordination issues, and loss of physical coordination. However, interestingly, fewer than 20% of patients present all three symptoms.
The following symptoms should raise concerns for Wernicke-Korsakoff syndrome:
- Confusion, memory loss, disorientation, and making up information to cover memory gaps (seen in up to 82% of patients)
- Eye issues such as unusual eye movements, bleeding in the retina, weakened eye muscles, palsy in cranial nerve IV, and problems with coordinated eye movements
- Unsteady walk
Specific cognitive issues seen in Korsakoff syndrome and not Wernicke encephalopathy include problems with creating new memories, recall of past events, and struggles with judgment, planning, and problem-solving due to executive function issues. These issues result in a standout symptom of confabulations, where a person originates false details to fill gaps in memory.
The Caine criteria are useful in diagnosing Wernicke encephalopathy, especially in people with chronic alcoholism. These criteria have a sensitivity of 85%, meaning they correctly identify 85% of individuals with Wernicke encephalopathy, and a specificity of 100%, meaning they correctly identify those without the disease. Given the significant overlap, these criteria also help in identifying Korsakoff syndrome.
The Caine criteria include diagnosing Wernicke encephalopathy when at least two out of the following four symptoms are present:
- Nutritional deficiency
- Eye movement abnormalities
- Problems with cerebellar function (mainly coordination and balance)
- Either confusion or mild memory impairment
Testing for Korsakoff Syndrome
Korsakoff syndrome is a condition that is mainly diagnosed based on the signs and symptoms a patient displays, especially if they have risk factors for a vitamin B1 (thiamine) deficiency. These signs and symptoms might include confusion, loss of memory and problems with coordination.
Although a blood test can measure the levels of thiamine in your body, the results can take several days. So, if your doctor suspects Korsakoff syndrome, they may start treatment right away instead of waiting for the test results. This is because the condition can get worse very quickly if not treated promptly.
Your doctor may also order a brain imaging scan like a CT or MRI. However, these tests are not often needed urgently to diagnose Korsakoff syndrome. They’re more commonly used to rule out other potential causes of your symptoms. A follow-up MRI scan can reveal specific changes in certain parts of the brain associated with Wernicke-Korsakoff syndrome. However, it’s worth noting that these specific changes are only present in about 53% of cases.
Treatment Options for Korsakoff Syndrome
The standard treatment for a sudden onset of Korsakoff syndrome is to replenish the body’s supplies of a vitamin called thiamine. While there isn’t a solid consensus on how much thiamine should be given, it’s often administered in high doses by injection.
Along with thiamine, it’s also important to correct any abnormalities in the body’s electrolyte balance and to ensure the patient is properly hydrated. Magnesium, for example, is particularly important as certain enzymes that rely on thiamine don’t work properly without it. Many patients will also need their blood sugar levels boosted, and while it used to be thought that doing this before giving thiamine could worsen symptoms, a review of many different papers has suggested that it’s best not to delay treating low blood sugar.
There’s some evidence to suggest that long-lasting, rather than short-term, treatment of low blood sugar without supplementing thiamine can increase the risk of a condition called Wernicke encephalopathy, which often accompanies Korsakoff syndrome.
Once the patient’s vitamin and electrolyte levels are stabilized, it can be beneficial to start memory rehabilitation. Korsakoff syndrome tends to most severely impact declarative memory, or “knowing what”, which often leads to patients needing care for the rest of their lives. However, Korsakoff patients often maintain some level of procedural learning, or “knowing how”, so focusing on this area in memory rehabilitation has shown promise. There’s been some success in helping Korsakoff patients improve their autonomy by better learning procedures.
What else can Korsakoff Syndrome be?
When a patient shows certain symptoms, the doctor has to figure out what’s causing them. This is known as a differential diagnosis. In this case, the doctor may consider a number of possible causes, including:
- Some kind of infection
- A seizure
- Intoxication, or the effects of alcohol or drugs
- Metabolic disorders, which are issues with the chemical reactions in the body
- Side effects of medications
- Stroke
- A head injury
- A brain tumor or mass
- Multiple sclerosis, a disease that affects the brain and spinal cord
- Migraines
- Vertigo, a sense of spinning or dizziness
- Ethanol neurotoxicity, damage to the brain or nervous system caused by alcohol
- Schizophrenia, a mental disorder that affects a person’s thinking, feeling, and behavior
What to expect with Korsakoff Syndrome
It’s crucial to suspect Wernicke’s encephalopathy early in order to improve a patient’s future health. Traditionally, it was believed that once a person develops Korsakoff syndrome, which is a severe form of memory loss often seen in people with Wernicke’s encephalopathy, this memory loss was generally permanent. However, recent studies suggest that memory rehabilitation techniques, including memory compensation (methods used to assist memory) and mistake less learning strategies (approach wherein the person isn’t allowed to make a mistake while learning), can be beneficial.
Additionally, brain imaging studies reveal that certain changes to the brain’s structure, specifically in the cortex (outer layer of the brain), are associated with a worse outcome for the patient.
Preventing Korsakoff Syndrome
Wernicke-Korsakoff syndrome, a brain disorder often linked to alcohol abuse, is typically not diagnosed until it reaches a severe stage. This can occur because the affected individuals might not seek medical help due to ongoing substance abuse. Sometimes, they aren’t evaluated until their family members bring them in for evaluation. Assertions from alcohol withdrawal or intoxication can also mask the symptoms and make it harder to diagnose the condition.
Moreover, when individuals do see a doctor, Wernicke-Korsakoff syndrome is often misdiagnosed. It’s estimated that this brain disorder is overlooked in about 68% of patients with a history of alcohol abuse and up to 94% of patients who do not abuse alcohol.
Another challenge in recognizing and studying Wernicke-Korsakoff syndrome is due to the absence of a standard definition for Korsakoff syndrome, one part of this two-part disorder. This makes it hard to collect reliable data about the condition’s prevalence, how to identify it, and what its eventual outcome may be.
Patients who cannot or do not wish to stop using alcohol may still find some benefit from maintaining good nutrition and taking dietary supplements, specifically thiamine (Vitamin B1), which can help mitigate some symptoms of the syndrome.
