Korsakoff syndrome

Korsakoff syndrome

Overview

Korsakoff syndrome is a chronic memory disorder caused by severe deficiency of thiamine (vitamin B-1). Korsakoff syndrome is most commonly caused by alcohol misuse, but certain other conditions also can cause the syndrome.

Thiamine helps brain cells produce energy from sugar. When levels fall too low, brain cells cannot generate enough energy to function properly. Korsakoff syndrome is most commonly caused by alcohol misuse, but can also be associated with AIDS, cancers that have spread throughout the body, chronic infections, poor nutrition and certain other conditions. It is also common in people whose bodies do not absorb food properly (malabsorption). This can sometimes occur with a chronic illness or after weight-loss (bariatric) surgery.

Korsakoff syndrome is often — but not always — preceded by an episode of Wernicke encephalopathy, which is an acute brain reaction to severe lack of thiamine. Wernicke encephalopathy is a medical emergency that causes life-threatening brain disruption, confusion, staggering and stumbling, lack of coordination, and abnormal involuntary eye movements.

Because the chronic memory loss of Korsakoff syndrome often follows an episode of Wernicke encephalopathy, the chronic disorder is sometimes known as Wernicke-Korsakoff syndrome. But Korsakoff syndrome can also develop in individuals who have not had a prior episode of Wernicke encephalopathy.

Symptoms

Korsakoff syndrome causes problems learning new information, inability to remember recent events and long-term memory gaps. Memory difficulties may be strikingly severe while other thinking and social skills are relatively unaffected. For example, individuals may seem able to carry on a coherent conversation but moments later are unable to recall that the conversation took place or with whom they spoke.

Those with Korsakoff syndrome may "confabulate," or make up, information they can't remember. They are not "lying" but may actually believe their invented explanations. Scientists don’t yet understand the mechanism by which Korsakoff syndrome may cause confabulation. The person may also see or hear things that are not there (hallucinations).

Causes and risk factors

Scientists don't yet know exactly how Korsakoff syndrome damages the brain. Research has shown that severe thiamine deficiency disrupts several biochemicals that play key roles in carrying signals among brain cells and in storing and retrieving memories. These disruptions destroy brain cells and cause widespread microscopic bleeding and scar tissue. Researchers have identified several genetic variations that may increase susceptibility to Korsakoff syndrome. Poor nutrition also may raise risk.

Most cases of Korsakoff syndrome result from alcohol misuse. Scientists don't yet know why heavy drinking causes severe thiamine deficiency in some alcoholics, while others may be affected primarily by alcohol's effects on the liver, stomach, heart, intestines or other body systems. Sign up for our e-news to receive updates about Alzheimer’s and dementia care and research.

Korsakoff syndrome may sometimes be associated with disorders other than alcohol misuse, including anorexia, overly stringent dieting, fasting, starvation or weight-loss surgery; uncontrolled vomiting; AIDS; kidney dialysis; chronic infection; or cancer that has spread throughout the body.

Diagnosis

Korsakoff syndrome is a clinical diagnosis representing a physician's best judgment about the cause of a person's symptoms. There are no specific laboratory tests or neuroimaging procedures to confirm that a person has this disorder. The syndrome may sometimes be hard to identify because it may be masked by symptoms of other conditions common among those who misuse alcohol, including intoxication or withdrawal, infection, or head injury.

 Experts recommend that a medical workup for memory loss or other cognitive changes always include questions about an individual's alcohol use. Anyone admitted to the hospital for an alcohol-related condition should be professionally screened for memory loss and cognitive change. The screening should include supplementary questions to assess recent memory. If screening suggests impairment, the person should receive a more detailed cognitive workup.

Treatment

Some experts recommend that heavy drinkers and others at risk of thiamine deficiency take oral supplements of thiamine and other vitamins under their doctor’s supervision.

Many experts also recommend that anyone with a history of heavy alcohol use who experiences symptoms associated with Wernicke encephalopathy, including acute confusion, prolonged nausea and vomiting, unusual fatigue or weakness, or low body temperature or blood pressure, be given injectable thiamine until the clinical picture grows clearer.

Once acute symptoms improve, individuals should be carefully evaluated to determine if their medical history, alcohol use and pattern of memory problems may be consistent with Korsakoff syndrome. For those who develop Korsakoff syndrome, extended treatment with oral thiamine, other vitamins and magnesium may increase chances of symptom improvement. If there is no improvement, consideration should be given to treatment of comorbid deficiencies and medical conditions, and the need for long-term residential care or supportive accommodation.

Abstaining from alcohol and maintaining a healthy diet is a cornerstone of effective long-term treatment. Those with Korsakoff syndrome have a reduced tolerance for alcohol and may be at high risk for further alcohol-related health problems.

Type of Doctor Department : A Neurologist, a Psychiatrist, or an Addiction Medicine Specialist