Alcohol symposium Flashcards
Define alcohol
“Alcohol” is non-specific, and includes methanol, ethanol, propanol etc.
In usual parlance, however, alcohol often means ethanol.
Name two enzymes involved in the metabolism of alcohol
Alcohol dehydrogenase
Aldehyde dehydrogenase
What is ethanol metabolised to?
Acetate
What can happen if you drink methanol?
Can become blind since when metabolised by the same enzymes in same way of ethanol to form formic acid
Describe the redox alteration caused by alcohol
Stimulates fatty acid synthesis, which are then esterified with glycerol and stored as triglyceride
NADH interferes with gluconeogenesis
Describe the oxidant stress alcohol causes
Lipid peroxidation which is associated with both acute tissue damage & fibrosis
Free radicals attack cellular & mitochondrial DNA causing deletions & mutations
What is 1 unit?
1 Unit = 10mL or 8g of pure alcohol
What is the current national limit for alcohol a week?
14 units
What is the current limit for driving and alcohol?
≤ 2-3 units in females
≤ 3-4 units in men
Describe alcoholic ketoacidosis
Metabolic acidosis with increased anion gap.
Chronic alcoholics, binge with little nutrition intake & with persistent vomiting which might cause metabolic alkalosis.
Pathophysiology : Extracellular volume depletion Glycogen depletion Increased NADH/NAD ratio Insulin suppressed Lipolysis and ketones increased (beta hydroxybutyrate)
How can ethanol cause hypoglycaemia? State the treatment of this
Ethanol causes hypoglycaemia through:
decreased intake of glucose (CHO),
depletion of glycogen,
blockade of gluconeogenesis
Prompt treatment with glucose is life-saving
Need to give parenteral thiamine as well to prevent CNS damage in case there is also thiamine deficiency
List the endocrine effects of alcohol
Decreased testosterone (testicular atrophy)
Pseudo Cushings
Metabolic Syndrome and Dyslipidaemia
List some general nutrition issues caused by ethanol
Low calcium (diet, decreased vitamin D)
Low phosphate (diet, increased PTH)
Low Mg, K (diet, hyperaldosteronism)
Can alcohol cause hypertension?
Yes but mechanism not clearly understood
How does alcohol cause thiamine deficiency?
Ethanol interferes with GI absorption
Hepatic dysfunction, which hinders storage and activation
Malnourishment
List some functions of the liver
Fat metabolism Carbohydrate metabolism Protein metabolism Storage Intermediate metabolism Secretion
List some hepatic responses to injury
INFLAMMATION
CELL DEATH
REGENERATION
FIBROSIS (SCARRING)
What can excessive alcohol intake cause?
Fatty liver (steatosis) - early, reversible
Alcoholic (steato-) hepatitis with chronic abuse, reversible
Fibrosis (scarring)
CIRRHOSIS
List the complications of cirrhosis
PROGRESSIVE LIVER FAILURE
HEPATOCELLULAR CARCINOMA
PORTAL HYPERTENSION
What is liver failure?
REDUCED HEPATOCYTE FUNCTION
Decreased protein synthesis
Decreased detoxification
What is portal hypertension?
ASCITES
CONGESTIVE SPLENOMEGALY
HEPATIC ENCEPHALOPATHY
PORTOSYSTEMIC SHUNTS
Which approaches are likely to be the most effective for reducing alcohol-related harm at the population level?
Targeting high-risk individuals
Genetic predisposition
Family history
Earlier drinkers
Describe the information, motivation, behavioural model
If people are to adhere to guidelines then they must have:
information - be exposed to and understand the guidelines
motivation - consider the guidelines to be meaningful / relevant
behavioural skills - know how to the apply guidelines to own behaviour
What is the purpose of personalised feedback?
personalised feedback does help to improve information motivation behavioural skills … but it is resource intensive
What is good about dry january?
Abstinence challenges allow people to
- perform “behavioural experiments”
- boost motivation
- enhance behavioural skills
- may have longer-lasting effects
- encourage discussions / “change the conversation” about alcohol
Why is a psychosocial approach required?
qualitative (and quantitative) studies show the importance of social context and social factors
+ behavioural experiments
interventions and attempts to motivate people must acknowledge this
? concerns about health
? concerns about fitting in
? concerns about reputation, image, weight, etc.
benefits of change - message framing
In terms of earnings who is (a) more likely to drink and (b) more likely to be admitted to hospital as a result of alcohol?
(a) high earners
(b) those from a deprived population
Describe the drinking habits of young people
Less likely to drink but when they do they drink more heavily
Describe the relationship between alcohol and violence
Domestic violence - 1/3 alcohol related
RTAs – 1 in 7 of those killed on UK roads
Impact on children – collateral – 1/5 of all calls to Childline are related to parents alcohol consumption
How is consumption estimated?
- Reported consumption: population surveys – e.g. Health Survey of England, Safe and well Schools Survey
- Taxation data from HMRC
Consistently underestimated by 40 - 60%
One third of UK population are drinking above hazardous levels
Give examples of policies to reduce consumption and limit harm
Minimum Unit pricing
Sensible on strength
Cumulative impact zone
What is alcohol withdrawal?
Physiological dependence
The ‘need’ to drink to avoid unpleasant symptoms - ‘Relief Drinking’
Delirium Tremens
List some symptoms of alcohol withdrawal
Tremor/shaking Sweating Tachycardia Nausea Agitation Siezures Visual hallucinations
Describe the difference between planned and unplanned alcohol withdrawal
Planned:
- in community
- in hospital
Unplanned:
- known alcohol problems + another
medical problem
- alcohol history not known in patient
presenting with a separate problem
When do the symptoms of alcohol withdrawal appear after admission?
Often occurs 2-3 days after admission
Which drugs are used to manage alcohol withdrawal?
DIAZEPAM: e.g. 10-20mg qds with reducing dose over 5-10 days
CHLORDIAZEPOXIDE
List some potential hazards of managing alcohol withdrawal
Severe liver disease - precipitation of hepatic encephalopathy
Respiratory depression
Reluctance to prescribe more
Concomitant alcohol consumption
Describe delirium
Disturbance of consciousness
Change in cognition or a perceptual disturbance (hallucination)
Onset of hours to days, and tendency to fluctuate.
Behaviour overactive or underactive; sleep often disturbed, loss of normal circadian rhythm.
Other features include: disorganized thinking, poor memory, delusions and mood lability
What is the importance of thiamine (vitamin B 1)?
Glucose and lipid metabolism
Production of amino acids
Production of glucose derived neurotransmitters
How is thiamine deficiency caused?
Alcoholism
Excessive vomiting
Famine
What is Wernicke’s Encephalopathy? State the signs
Brain damage:
Multiple small haemorrhages especially in upper brainstem, hypothalamus and thalamus, mamillary bodies
Signs include confusion, eye signs and ataxia
What is Korsakoff’s Psychosis?
Permanent brain damage
Severe short term memory loss
Confabulation
Describe how people become alcohol dependant and why they experience withdrawal symptoms
Symptoms of alcohol withdrawal occur because alcohol is a central nervous system depressant. Alcohol simultaneously enhances inhibitory tone and inhibits excitatory tone. Only the constant presence of ethanol preserves homeostasis. Abrupt cessation unmasks the adaptive responses to chronic ethanol use resulting in over activity of the central nervous system.
If you drink a lot, for a long time, your central nervous system adapts by working harder to maintain equilibrium.
If you then suddenly stop drinking, it continues to overwork which gives rise to withdrawal symptoms.
Describe how a non medical detox works
- Planned reduction
- Drink diaries
- Stabilisation
- Gradually reduce (5 units per day?)
- Consider form of alcohol, strength and size of ‘vessel’
- Which drinks to not have? (e.g. start later, await withdrawal symptoms, plan day)
