Alcohol and Substance Abuse Flashcards
Definition of psychoactive substance, harmful use and hazardous use
Psychoactive substance: has effect on CNS
Harmful use: CAUSE adverse consequences, without dependence e.g. health, safety, interpersonal relationships
Hazardous use: place user AT RISK OF adverse consequences, without dependence
Hx taking
All substances used
Pattern of use - frequency, dosage, typical day (stereotyped pattern? 規律), daily consumption
Route of access
When, why
Features of dependence
Related physical (GI, Neurocognitive) and social disability (work, finance, housing, accidents, crime, marital)
Related neuropsychiatric disorders
Past history of psychiatric illness/substance misuse
FHx
CAGE questionnaire for alcohol
- any need to Cut down, ever had people Annoyed and criticise about drinking, ever felt Guilty, need Eye-opener?
Physical examination for alcohol/substance
- nutritional status
- evidence of acute use or intoxication e.g. pupil constriction in opiate use, incoordination/slurred speech in alcohol use
- signs of withdrawal e.g. tremor, sweating, n/v, tachycardia, pupil dilation
- short term complications e.g. head injury, infection by IVDA
- long term complications e.g. CLD, HBV/HCV/HIV in IVDA
Investigations for alcohol/substance
Urine or saliva drug screening CBC - MCV U&E LFT - GGT, AST, ALT Clotting - prolonged PT in liver damage ECG HBV/HCV/HIV if IVDA
Aetiology of alcohol related disorders - biology, psychological, presence of other illnesses, social and environmental
Biological
- strong genetic component
- deficiency in aldehyde dehydrogenase (50% East Asians) = reduced alcohol consumption and dependence
- chronic alcohol consumption = decrease GABA activity and increase glutamate –> increase neuroexcitability on intoxication and withdrawal seizures on cessation
Psychological
- positive reinforcement: pleasant effects of alcohol consumption
- negative reinforcement: negative effects of withdrawal
- modelling (relatives and peers)
Presence of psychiatric or physical illness increases risk of alcohol abuse and dependence
- self-medication
- coping mech
- impulsivity, lack of insight into risks, lack of support
Social and environmental
- cultural attitude
- association of certain occupations with death from alcoholic liver disease e.g. leisure, catering, doctors, journalists
- frequent significant life events
Harmful use of alcohol - safe limits, complications of excessive use
Safe limits
- men: 3-4 units/day (<21/wk)
- women: 2-3 units/day (<14/wk)
(1 small glass of wine = 1 unit; 1 can of beer = 1.5 units; 1 catty of Chinese wine = 16 units; 1 bottle of brandy = 30 units) - vol in L x % alcohol = units
[alcohol can protect from CHD in men >40 and postmenopausal women; max 1-2 units/day]
Complications of excessive alcohol use
- psychological: self-harm
- social: absenteeism, legal problems/violence, interpersonal problems
- physical:
- -> delirium tremens, seizures, wernicke-korsakoff, cerebellar degeneration, haemorrhagic stroke
- -> alcoholic liver disease, pancreatitis, peptic ulceration, cancers
- -> HT, IHD, arrhythmias
- -> hypoBG, hyperTG, hyperUr, hypoMg, hypoPO4, hypoNa, pseudo-Cushing’s
- -> macrocytosis, anaemia, neutropenia
- -> osteoporosis, myopathy
- -> fetal alcohol syndrome, intrauterine growth retardation, impotence
- -> increased trauma risk
Alcohol Use Disorder (alcohol dependence syndrome)
AT LEAST TWO of the following, in a 12 MONTH PERIOD:
- alcohol taken in larger amounts or over a longer period than intended
- persistent desire or unsuccessful efforts to cut down or control use (have they tried? result? why fail?)
- craving (compelled to drink) 心癮
- failure in fulfilling major role obligations at work/school/home
- continued use despite having persistent social or interpersonal problems
- primacy – important activities are given up or reduced because of alcohol use (家庭,工作,興趣,飲酒 - which is most important)
- recurrent use in physically hazardous situations e.g. driving
- continued use despite having knowledge of having persistent or recurrent physical or psychological problem
- tolerance
- -> need for increased amounts to achieve desired effect or diminished effect with use of same amount
- withdrawal
- -> characteristic symptoms e.g. sweating, palpitations, tremor, n/v or respite drinking (take to relieve/avoid symptoms)
Epidemiology and Aetiology of AUD
Male 3%, Female 0.4%
(middle aged, unemployed, chronic drinking)
Aetiology
- neurochemical basis for dependence: ethanol increases fluidity of membrane lipid, hence later varies receptors’ function
- -> anxiolytic - increase Cl- flux effect of GABA on GABA receptor
- -> stimulant - increase release of DA in forebrain projections to nucleus accumbens (via opioid release)
- -> anaesthetic - inhibitory action on NMDA receptors for glutamate
Genetics
- 60%
- polymorphism of ADH and ALDH has protective effects
CAGE questionnaire for alcoholism sensitivity and specificity
Sensitivity 39-83%
Specificity 92-96% (score>2)
Management of AUD - what to rule out, controlled drinking vs abstinence, pharmacological Tx
- RULE OUT COMPLICATIONS and treat comorbidities
- LFT, injury, anaemia, ulcer
- drug abuse, depression - Controlled drinking vs abstinence
- controversial evidence of efficacy
- no more than 2 (1) drinks per day
- NOT SUITABLE FOR CLEARLY DEPENDENT PATIENTS (chronic drinker with complications, failure to abstain – likely to relapse once taste alcohol)
- suitable for patients with good social support - Detoxification
- done inpatient if there are risks of failing/past complications/co-morbidities
- LONG ACTING BZD e.g. Diazepam (valium) to substitute alcohol with CNS suppression
- Gradual TAPERING DOSE OVER A WEEK (consume liquid, oral vitamins)
- relieve severe symptoms and reduce risk of developing withdrawal seizures or DT - Thiamine, parenterally or orally
- easy deficiency in alcoholics due to interrupted absorption in small intestine
- to prevent Wernicke-Korsakoff syndrome
- IV for immediate cases (prevent wernicke encephalopathy)
- +2 yrs oral for Korsakoff syndrome - Disulfuram or Naltrexone (MAINTENANCE therapy)
- disulfuram suppresses aldehyde dehydrogenase to increase aldehyde and vasodilation/flushing/palpitations/headache/nausea after drinking (taken orally, need supervision)
- Naltrexone - opioid antagonist to prevent relapse by decreasing DA effect in stimulant pathway to reduce craving for alcohol and reduce pleasant effect
- -> >3-4 months treatment, check liver enzymes
Management of AUD - non-pharmacological
Also for maintenance
Psychotherapies
- CBT (set goals, alternative response to triggers, interpersonal/social problems, behavioural contracting, relapse prevention)
- Self-help groups
- motivational interviewing to assess stage of change
Psychoeducation, skill development
Social support: social workers, probation officers
Others
- avoid high risk settings or old acquaintances
- set limits
- self-monitoring e.g. diary
- reward systems
- rate control (spacing out drinks)
AUD prognosis and prognostic factors
Poor prognosis
- 71% not in remission after 1 yr
- 66% not in remission after 5 yrs
Prognostic factors:
- severity, duration
- low IQ, impaired cognition
- personality
- social stability
- motivation
- comorbid mental disorders
Alcohol intoxication - risks, criteria
Potentially life threatening due to risk of respiratory depression, aspiration of vomit, hypoBG, hypothermia and trauma
- Recent ingestion
- Problematic behavioural/psychological changes e.g. aggression, mood lability, impaired judgement
- > 1 of the following:
- slurred speech
- incoordination
- unsteady gait
- nystagmus
- impairment of attention or memory
- stupor or coma - Not attributable to another medical condition and not better explained by another mental disorder (including other substances)
- -> may have anterograde amnesia (blackouts)
- -> idiosyncratic intoxication - very rare, senseless violent behaviour after small amount of alcohol, prolonged terminal sleep, total or partial amnesia about event
Alcohol withdrawal criteria and possible consequences
ALL states are potentially life threatening due to association with autonomic hyperactivity - MUST COVER WITH DIAZEPAM
- Cessation in alcohol use that has been heavy and prolonged
- > 2 of the following developing within several hrs-days:
- autonomic hyperactivity e.g. sweating, palpitations
- tremor
- insomnia
- nausea, vomiting
- transient hallucinations
- psychomotor agitation
- anxiety
- generalised tonic clonic seizure - Causes clinically significant distress or impairment
- Not due to another medical condition or another mental disorder (including other substances)
Possible consequences:
- uncomplicated withdrawal
- perceptual disturbances
- withdrawal seizures
- delirium tremens
Uncomplicated alcohol withdrawal syndrome - severity, onset, symptoms, Tx
Mild
4-12 hrs after cessation
Tremor, sweating, n/v Mood disturbance - anxiety, depression Hyperacusis Autonomic hyperactivity - tachycardia, HT, mydriasis, pyrexia Sleep disturbance Psychomotor agitation
Tx: BZD (long acting) - give loading dose then reassess Q1H vitals
- prevent seizures
Alcohol withdrawal with perceptual disturbances and withdrawal seizures - onset, symptoms, Tx
Perceptual disturbances
- illusions or hallucinations (TYPICALLY VISUAL)
- delusions secondary to hallucinations
Tx: Haloperidol (also sedative)
Withdrawal seizures (“rum fit seizures”)
- 6-48 hrs after cessation
- 5-15% patients
- generalised tonic clonic
- can be life threatening and occur without any other symptoms
- predisposing: previous Hx, concurrent epilepsy, hypoK or Mg
Tx: phenytoin for seizures
Delirium Tremens - severity, onset, symptoms, course, mortality, ddx
SEVERE
1-7 days after cessation
Altered consciousness and marked cognitive impairment (disorientation, confusion, agitation, inattention etc.) - fluctuating
Vivid hallucinations and illusions
Marked tremor
Autonomic arousal (heavy sweating, raised BP/HR, fever)
Paranoid delusions
Course:
2-4 days if untreated
5-15% mortality from CVS collapse, hypo/hyperthermia, infection
Predisposing factors: physical illness
5-20% patients undergoing detox
Ddx: other causes of delirium
Management of Delirium Tremens - environment, medications, monitoring
Emergency hospitalisation
Environment - well lighted, quiet room
Search for MEDICAL COMPLICATIONS e.g. infection, head injury, liver failure, GI haemorrhage, Wernicke’s encephalopathy –> ADMIT TO MEDICAL if any
Hydration
Medication
- HIGH DOSE BZD e.g. DIAZEPAM
- antipsychotics e.g. HALOPERIDOL for severe psychosis
- HIGH DOSE PARENTERAL THIAMINE (not oral in DT)
Monitoring –> alcohol withdrawal chart
- temperature – hyperthermia
- fluid – dehydration
- electrolytes – hypoMg, hypoK
- glucose – hypoBG
(other general measures for delirium refer to other deck)