Describe the two components of the Wernicke-Korsakoff syndrome. Discuss the role of thiamine in your answer

Question

What will be an ideal response?

Answer 1

Answer: Chronic alcohol consumption can produce longer-lasting deficits in the way an individual solves problems, remembers information, and organizes facts about his or her identity and surroundings. These cognitive deficits are commonly referred to collectively as alcoholic
dementia and are associated with structural changes in brain tissue. Specifically, there is an enlargement of brain ventricles (the interior fluid-filled spaces within the brain), a widening of fissures separating sections of cerebral cortex, and a loss of acetylcholine-sensitive receptors. The combination of these effects results in a net decrease in brain mass, as indicated in CT and MRI brain scans, and a decline in overall intelligence, verbal learning and retention, and short-term memory, particularly for middle-aged and elderly alcoholics.
Some 50 to 75 percent of all detoxified alcoholics and nearly 20 percent of all individuals admitted to state mental hospitals show signs of alcohol-related dementia. Through abstinence, it is possible to reverse some of the cognitive deficits and even some of the abnormalities in the brain, depending on the age of the alcoholic when treatment begins. As you might suspect, younger alcoholics respond better than older ones.

A more severe form of cognitive impairment related to chronic alcohol consumption is a two-part disease referred to as Wernicke-Korsakoff syndrome. In Wernicke's encephalopathy
or simply Wernicke's disease, the patient shows confusion and disorientation, abnormal eye
movements, and difficulties in movement and body coordination. These neurological problems arise from a deficiency in vitamin B1 (thiamine), a nutrient required for neurons in the brain to consume glucose. Extreme alcoholics may go days or weeks at a time eating practically
nothing and receiving calories exclusively from drinking alcoholic beverages.

As a result of thiamine deficiency, large numbers of neurons die in areas of the brain specifically concerned with thinking and movement. About 15 percent of patients with Wernicke's disease, however, respond favorably to large amounts of thiamine supplements in combination with abstinence from alcohol, restoring their previous level of orientation, eye movements, and coordination.

In some cases, Wernicke's disease patients, whether or not they recover from confusion and motor impairments, also display a severe form of chronic amnesia and general apathy called Korsakoff's psychosis. Such patients cannot remember information that has just
been presented to them and have only a patchy memory for distant events that occurred prior to their alcoholic state. They frequently attempt, through a behavior called confabulation, to compensate for their gaps in memory by telling elaborate stories of imagined past events, as if trying to fool others into thinking that they remember more than they actually do.

Thiamine deficiency is linked to Korsakoff's psychosis as well. After being treated with thiamine supplements, about 20 percent of patients completely recover their memory and 60 percent partially recover it. Yet the remaining 20 percent, generally the most severely
impaired patients and those with the longest history of alcohol consumption, show little or no improvement and require chronic institutionalization.