Substance Misuse Disorders Flashcards
Definition of dependance
- Needing to use a substance to feel or function normally, after a period of regular use. Recognised by a cluster of physiological, behavioural and cognitive symptoms in which the use of a substance takes on a much higher priority than other behaviours that once had a greater value. Dependence can be both physical and psychological
- Features of dependence include: Tolerance, compulsion, withdrawal (physiological state), loss of control, Continued use despite harm, salience (obtaining the substance becomes more impotant than other social priorities) reinstatement after abstinence and narrowing of repertoire.
Definition of withdrawal
Transient state which occurs whilst the body readjusts to lower levels of the substance
Lifetime prevalence of alcohol dependence, drug dependence, any use disorder
Alcohol dependence (5.4%), Drug dependence (3.0%), Any substance use disorder (14.6%)
Male to female ratios for alcohol dependence and substance use disorders
2:1 for alcohol use disorders, 4:1 for substance use disorders in general
Definition of binge drinking
- (>8 units for men or >6 units for women) > constitutes 27% of UK alcohol consumption
Main aetiological factor in substance use disorders
- Genetics: Family, twin and adoption studies suggest that the heritability of substance use disorders is around 40-60%. This may be accounted for by personality traits in part i.e impulsivity, anxiousness/ avoidance. May also involve having low DR2 levels, making patients seek external pleasures to compensate for low endogenous dopamine stimulation
Other factors (aside from genetics) which predispose to substance use disorders
- Childhood and life experiences: RFs include low parental socioeconomic status, ineffective parenting, family breakdown and abuse. More commonly have conduct disorders as children
- Occupation: stress and sanctioned drinking increases the risk of alcohol dependency
- Psychiatric illness: Associated with PD, depression, BPAD, ADHD, psychosis and anxiety disorders
What ‘theories of dependence’ exist which explain substance use disorders
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Learning Theories:
- Classic (Pavlovian) Conditioning- Cravings become conditioned to cues and the cue itself can trigger craving, causing drug-seeking behaviour (e.g seeing a needle)
- Operant (Skinnerian) Conditioning- depends on repetitive behaviours having predictable outcomesà Behaviours which are rewarded are repeated (positive reinforcement), and also behaviours which relieve unpleasant experiences (negative reinforcement)
- Motivational Theory: ‘stages of change model’
- Neurobiological Models: Most addictive drugs strongly increase synaptic dopamine levels in the reward pathway. The brain then adjusts by reducing natural dopamine production; addiction may then develop as the patient becomes dependant on this external dopamine ‘rush’
Clinical presentation of alcohol use
Clinical presentation of intoxication includes slurred speech, ataxia, increasing sedation and confusion. Withdrawal symptoms present as blood alcohol levels fall: headache, nausea, vomiting, tremor and sweating, insomnia, anxiety, agitation and tachycardia.
How to calculate units of alcohol and Uk guidance on consumption
- 1 unit of alcohol is 8g of pure alcohol. Units= volume (litres) x alcohol by volume (ABV, %)
- 1 unit is equivalent to: ½ a pint, 1 small glass of wine, 1 standard measure of spirits
UK low-risk drinking guidelines are the same for men as for women: maximum 14 units a week spread over 3 days in that week
Physical complications of alcohol misusue
- Liver: alcoholic hepatitis (malaise, hepatomegaly and ascites)
- GI: pancreatitis, oesophageal varisces, gastritis and peptic ulceration
- Neurological: peripheral neuropathy, seizures and dementia
- Cancer: bowel, breast, liver, oesophageal
- CV: HTN and cardiomyopathy
- Head injuries and accidents when intoxicated- increased risk of subdural haematoma
- Fetal alcohol syndrome
Psychological complications of alcohol misuse
- Depression, anxiety, self-harm and suicide
- Amnesia
- Cognitive impairment- either alcoholic dementia or Korsakoff’s syndrome
- Alcoholic hallucinosis
- Morbid jelousy
Social complications of alcohol misuse
Social issues including unemployment, absenteeism, domestic violence, sexual exploitation and divorce may follow alcoholism and perpetuate it.
Wernicke’s encephalopathy causes and presentation. What is the main complication
Wernicke’s Encephalopathy: A medical emergence caused by acute thiamine (vitamin b1) deficiency. Presents with a classic TRIAD of 1. Confusion 2. Ataxia 3. Ophthalmoplegia. If left untreated this will progress to Korsakoff’s syndrome- irreversible anterograde amnesia, whereby patients can register new events but cannot recall them after a few minutes. Patients may confabulate.
Delirium tremens cause and presentation
Delirium Tremens: A medical emergency which occurs around 48 hours after abstincence from alcohol and which may last 3-8 days. Presents with confusion, hallucinations (especially visual), affective changes (extreme fear or hilarity), gross tremor, autonomic disturbances such as sweating or tachycardia. Has a 5% mortality rate and up to 30% if untreated or complicated
Management of delirium tremens
A reducing regimen of benzodiazepines alongside parenteral thiamine (pabrinex). Need to correct dehydration and electrolyte disturbances (can use a longer-acting benzo such as diazepam or chlordiazepoxide)
General investigations for alcohol dependance
- Physical health screen: patients with alcohol dependency can neglect themselves so need to examine fully and broadly (guided by Hx e.g ECG, BG etc)
- FBC: may develop macrocytic anaemia due to B12 deficiency
- LFTs: raised transaminases suggests hepatocellular damage, raised GGT suggest recent heavy alcohol use.
- UDS
Questionnaires used for alcohol dependance
AUDIT, CIWA-Ar (grades withdrawal symptoms to inform treatment), APQ (assesses the severity and extent of problems arising from the alcohol use), Severity of Alcohol Dependence Questionnaire (SADQ)
CAGE questions
- Have you ever felt you need to CUT DOWN on your drinking?
- Do you every feel ANNOYED if people criticise your drinking?
- Have you ever felt GUILTY about your drinking?
- Do you ever need an EYE OPENER to steady yourself in the morning?
Process of assisted withdrawal (uncomplicated)
- Give Pabrinex if they are at risk of Wernicke’s encephalopathy
- Council patient on expectations: withdrawal symptoms are worst within the first 48 hours, take about 3- 7 days after the last drink to completely resolve
- Gradually reduce alcohol consumption
- If >15 units/day or >20 on AUDIT, consider offering Community-based assisted withdrawal (best option)
- This can be done through organisations like CGL (Change, Grow, Live)
- Usually 2-4 meetings in the first week
- If complex, may need up to 4-7 days per week over a 3-week period
What is the purpose of ‘detox’
‘Detox’ reduces the discomfort and risk during alcohol withdrawal- it may be planned or unplanned. The severity of withdrawal symptoms should be determined using CIWA-Ar
When can detoxification be done in the community and when should a patient be referred for inpatient detoxification
Community detoxification can be offered for uncomplicated alcohol dependence, using a fixed dose regimen of benzos over 5-7 days. Inpatient detoxification is required if there is a history of:
- 30+ units/day
- 30+ on SADQ
- History of epilepsy, delirium tremens or withdrawal-related seizures
- Need concurrent withdrawal of alcohol and benzodiazepines
- Significant psychiatric comorbidity or significant learning disability
- Lower threshold for inpatient treatment in vulnerable groups (e.g. homeless, older people)
- Children (10-17)
- nobody at home to support the process.
First steps in alcohol withdrawal management
There is a need to establish goals: Abstinence is the best treatment goal, however, some patients may need more moderate goals. If comorbid mental health illnesses do not improve within 3-4 weeks of abstinence, must consider referring for specific treatment. > Motivational interviewing
Acute alcohol withdrawal management