Abstract
I read with interest the case report by Moriyama et al. that was recently published in your Journal[1]. The authors report a case that demonstrates repetition of episodes of Wernicke–Korsakoff syndrome and provides evidence supporting the hypothesized continuum between Wernicke–Korsakoff syndrome and alcoholic dementia.
Wernicke–Korsakoff syndrome is one of the gravest consequences of alcohol abuse and consists of mental, eye movement and gait abnormalities [2], [3]. The histopathological abnormalities of Wernicke–Korsakoff syndrome consist of variable degrees of neuronal, axonal, and myelin loss; prominent blood vessels; reactive microglia, macrophages and astrocytes; and sometimes, small haemorrhages. Lesions affect the thalamus (especially the dorsomedial nucleus and the medial pulvinar), the hypothalamus (especially the mammillary bodies), the midbrain (especially the oculomotor and periaqueductal areas) and the pons and medulla (especially the abducens and medial vestibular nuclei).
There may be a similarity between the effect of recurrent psychotic or depressive episodes and the effect of repeated episodes of Wernicke–Korsakoff syndrome. Repeated psychotic episodes may lead to cognitive decline in schizophrenia [4]. Recurrent depressive episodes may lead to cognitive impairment in depression [5]. Similarly, repeated episodes of Wernicke–Korsakoff syndrome may cause cognitive deterioration, especially in susceptible people. It is likely that early neurodevelopmental abnormalities set the stage for, or interact with, subsequent neuronal changes in schizophrenia, depression and alcoholism.
Persistent dementia in individuals with alcoholism can be attributed to Wernicke–Korsakoff syndrome alone or in combination with the other, common causes of dementia and certain conditions to which they are vulnerable. Poor nutrition, multiple trauma and the malfunctioning of the liver, the pancreas and the kidneys may contribute to the development of persistent dementia in patients with alcoholism. Future research may shed more light on the causes of alcohol-induced persistent dementia.