Neurological Complications of Alcohol Use

 

Neurological Complications of Alcohol Use

Neurological Complications of Alcohol Use -

1. Alcoholic Neuropathy

     a. Acute Alcoholic Neuropathy

    b. Alcohol-related - Compressive Neuropathy - Excessive alcohol consumption is traditionally associated with ‘Saturday night palsy’, caused by compression of the radial nerve against the humerus for several hours.

     c. Chronic Alcholic Neuropathy - The onset of symptoms is insidious and symmetric, predominantly sensory, in the form of dysesthesia, burning sensation and burning pain on the soles of the feet that later develops into cramp in the calves and the hands. Motor symptoms usually manifest later, and are characterised by muscle weakness and atrophy, especially in the distal muscles of the upper or lower limbs. Vegetative vascular and skin defects (sweaty, atrophic, glossy, almost hairless skin) with associated dysautonomia are also typical.

2. Withdrawl symptoms and delirium tremens - The manifestations of withdrawal syndrome include a wide range of severe symptoms, ranging from distal hand tremor, anxiety, insomnia and visual hallucinations to psychomotor agitation, autonomic hyperactivity, seizures or coma.

The most serious form, which usually appears 72h after withdrawal, is delirium tremens, characterised by disorientation, agitation and visual hallucinations, accompanied by autonomic signs such as hyperventilation, tachycardia and diaphoresis.

3. Wernicke's Encephalopathy - caused by a vitamin B1(thiamine) deficiency.

WE is characterised by the classic triad of oculomotor disturbance, ataxia and confusion. Ocular alterations are complex, and consist mainly of a combination of alterations such as, for example, horizontal or vertical nystagmus, unilateral or bilateral oculomotor paresis, or conjugate gaze palsy. Ataxia mainly affects the trunk by altering gait and balance; limb ataxia and dysarthria are less common. Confusion or encephalopathic symptoms, meanwhile, develop within days or weeks and are characterised by profound disorientation, inability to concentrate, apathy, indifference, inattention, drowsiness and coma.

WE is a medical emergency because it is potentially reversible and delayed treatment or no treatment at all can cause serious sequelae and even death.

4. Korsokoff's psychosis - is mainly caused by malnutrition associated with chronic alcoholism, thiamine deficiency.

It is characterised by memory impairment that is out of proportion to other cognitive functions in an awake, attentive and responsive patient. Important manifestations are learning deficits and memory loss, affecting both anterograde and retrograde events. Recent memory is usually more affected than remote memory, and the creation of false memories, or confabulation, in speech that can even be induced by questions about the patient's recent activities is characteristic of this syndrome.

5. Alcohol Related Dementia or brain damage - Neuronal damage or depletion, from a physiopathological perspective, is believed to be related to glutamate neurotoxicity, oxidative stress and diminished neurogenesis, triggered by chronic alcohol abuse.

It is characterised by an insidious onset with stepwise progression of symptoms that overlap with other neurodegenerative dementias. In the early stages, neuropsychological studies usually reveal frontal-subcortical cognitive impairment, with slowing of mental processes, attention deficit, changes in immediate or short-term memory, decline in visual spatial skills, and decline in executive functions, such as planning and organisation.

6. Marchiafava Bignami disease - rare entity that is characterised by progressive demyelination and necrosis of the central part of the corpus callosum.

Most patients present progressive dementia, usually subacute at onset, with predominance of apractic or aphasic disorders, oppositional hypertonia, dysarthria, frontal release reflexes and, sometimes, hemiparesis or signs of interhemispheric disconnection. Some patients also present decreased alertness and seizures.

7. Cerebellar Degeneration - Alcohol-related cerebellar degeneration is a common complication that affects up to 25% of alcoholics, and is one of the most frequent causes of acquired ataxia in adults.

Cerebellar degeneration is characterised by trunk ataxia with wide-based gait, instability and variable degrees of lower limb dysmetria. Dysmetria in the upper limbs, dysarthria or oculomotor disturbance are less common. In most cases, cerebellar degeneration evolves over a period of several weeks or months and persists for years.