WCS41 Classification And Diagnosis Of Psychiatric Illness

Question 1

History taking

Answer 1

• Open-ended question in history taking
• Avoid close-ended questions
• Ask patient to elaborate
• Focus 1 symptom at a time
• Following diagnostic criteria e.g. DSM

Question 2

Subjective experiences

Answer 2

• “Measurable” by clinical interview / self-report
  —> Type
  —> Severity
  —> Duration
  —> Clinical significance (how it affect daily life)
• Adopt a “time-frame” for assessment e.g. in the past week

Question 3

Type of symptoms

Answer 3

1. Abnormal experiences and behaviours
   - Hallucination, Delusion, Disorganised speech, Catatonia
2. Normal experiences but excessive in amount
   - Anhedonia, depressed mood, excessive worries, obsession and compulsion, flashbacks of traumatic events
   - Excessive, irrational, and uncontrollable
3. Impaired functioning
   - impaired cognitive functioning after traumatic brain injury
   - impaired social functioning e.g. deficits in social-emotional reciprocity in ASD
4. Impaired attention
   - ADHD
5. Impaired physiology
   - impaired sleep e.g. insomnia, hypersomnia, circadian sleep-wake disorder
   - impaired sex and gender function e.g. gender dysphoria, ED
   - impaired eating
   - impaired experience of pain and somatic symptoms
   - impaired elimination e.g. enuresis
6. Behavioural disturbances
   - addiction, including non-substances
   - impulse-control
7. Personality disorder

Question 4

Pros and Cons of classification

Answer 4

Pros:

• Bring order to great diversity of phenomena encountered in clinical practice
• Identify groups of patients with similar clinical features —> suitable treatment can be planned and likely outcome predicted
• Able to develop a standardised approach in diagnosis

Cons:

• labelling and stigmatisation
• benign labels may lead to misunderstanding of severity and treatment
• diagnostic term can have different meaning to different people
• distracts from understanding the problem unique to the individual
• some patients have mixture of disorder
• some patients cannot fit into a particular category i.e. Not Otherwise Specified

Question 5

Good classification system

Answer 5

1. High validity
   - limited evidence that different disorders have distinct qualities
   - current system depend heavily on subjective experiences and is based on clinical observation
   - system is valid for most cases except sometimes there are overlap
2. High reliability
   - clearer criteria —> higher reliability
   - there may be diagnostic disagreement between raters since diagnosis depends on identification of S/S (i.e. there are information and diagnostic variance)
3. Easy to use
4. Applicable across settings and cultures (e.g. GP, specialties settings)
5. Meet the needs of various users

Question 6

Incorrect diagnosis

Answer 6

Causes:

1. Incomplete / different information obtained in interview
   - lack of rapport and trust
   - feigned / exaggerated symptoms
   - inconsistency / denial
   - lack of informants
   - inadequate interviewing technique (can be improved by training / use of structured interview)
2. Inadequate use of diagnostic criteria
3. Wrong interpretation of information
4. Interviewers may differ in which is more important if 2 categories are both met

Solution:

1. Elaboration
2. Clarification
3. Collateral information collection
4. Longitudinal assessment

Question 7

Screening tools

Answer 7

1. PHQ-9
2. MDQ
3. Adult Autism Spectrum Quotient

Question 8

2 most commonly used classification systems in psychiatry care

Answer 8

1. DSM (Diagnostic and Statistical Manual of Mental Disorder)
   - definitions mostly descriptive
   - theoretical statements are avoided
   - etiology included only when clearly demonstrable
   - Multi-axial (5 axis: 1-5) to explain a mental illness
   —> Axis 1: Clinical disorders
   —> Axis 2 : Personality disorders
   —> Axis 3: General medical conditions
   —> Axis 4: Psychosocial and environmental problems
   —> Axis 5: Global assessment of functioning
2. ICD (International Classification of Diseases)

Question 9

Common elements of diagnostic criteria

Answer 9

1. Cluster of symptoms
   - Core symptoms (major depressive disorder, depressed mood, loss of interest)
   - Associated symptoms (sleep disturbance, reduced appetite, suicidal idea)
2. Minimal duration of symptoms (usually duration >1 month)
3. Distress / Impairment in functioning
4. Exclusion criteria

Question 10

Comorbidity in psychiatry

Answer 10

Example:
Bipolar
- personality disorder
- eating disorder
- ADHD
- sleep disorder
- anxiety disorder
- substance use disorder

Question 11

Diagnostic criteria of Schizophrenia

Answer 11

Characteristic symptoms:

• > =2 of following
• each present for a significant portion of time during a ***1 month period (or less if successfully treated):

1. Delusions
2. Hallucinations
3. Disorganised speech (e.g. frequent derailment / incoherence)
4. Grossly disorganised / Catatonic behaviour
5. Negative symptoms i.e. affective flattening (情感扁平化), alogia (poor thinking inferred from speech), avolition (lack of motivation)

Social / Occupational dysfunction:

• significant proportion of time
• > =1 major areas of functioning e.g. work, interpersonal relations, self-care markedly below level before onset

Duration: >=6 months

Exclusion: Schizoaffective, Mood disorder, Substance / General medical condition

Question 12

Mood disorders

Answer 12

Depressive disorders

• Single / Recurrent episodes
• Dysthymia (persistent mild depression)
• Premenstrual dysphoric disorder

Bipolar disorders
- manic / hypomanic / mixed and depressive episodes
(—> Manic: abnormally + persistently elevated / irritable mood
1. Grandiosity
2. **Decreased need for sleep
3. **Intensified speech
4. **Racing thoughts
5. Increased in goal-directed activity / **Psychomotor agitation
6. Excessive involvement in pleasurable activities that have a high-risk consequence
7. Distractibility
—> Hypomanic: similar but less intense to manic)

• manic / hypomanic / mixed episodes usually last ***1 week
• depressive episodes can last for ***weeks / months
• usually symptoms free during inter-episode period
• Bipolar 1, Bipolar 2, Cyclothymia

Question 13

Diagnostic criteria of Major Depressive Disorder

Answer 13

Characteristic symptoms:

• > =5 following present during same ***2 week period
• clear change from previous functioning
• > =1 symptoms has to be **Depressed mood / **Loss of interest, pleasure
• Can have ***Seasonal pattern

1. Depressed mood most of day
2. ***Marked diminished interest / pleasure in all activities
3. ***Significant weight loss
4. ***Insomnia / Hypersomnia
5. Psychomotor retardation / agitation
6. Fatigue / ***Loss of energy almost everyday
7. Feeling of worthlessness / excessive guilt
8. ***Diminished ability to think / concentrate
9. Recurrent thoughts of death

• Symptoms do not meet criteria for ***Bipolar mixed episode
• Symptoms cause clinically significant distress / impairment in social, occupational, other important areas of functioning
• Symptoms are NOT due to direct physiological effects of a substance / general medical condition
• Symptoms are NOT better accounted for by bereavement (persist for >= 2 months)

Question 14

Anxiety disorders

Answer 14

1. Generalised anxiety disorder
2. Panic disorder
3. Agoraphobia
4. Social phobia
5. Specific phobia
6. Separation anxiety disorder
7. Selective mutism
8. Anxiety disorder substance-induced / another medical condition
9. OS / US anxiety disorder

Question 15

Diagnostic criteria of Generalised Anxiety Disorder

Answer 15

• Excessive anxiety and worry occurring **more days than not for **>= 6 months, about a number of events / activities
• Difficult to control the worry
• Anxiety and worry are associated with >=3 of following:

1. Restlessness / Feeling keyed up / on edge
2. Easily fatigued
3. Difficulty concentrating / mind going blank
4. Irritability
5. Muscle tension
6. Sleep disturbance

• Clinically significant distress / impairment in functioning
• Disturbance are not due to substance / general medical condition

Question 16

Diagnostic criteria for Panic disorder

Answer 16

Discrete period of ***intense fear / discomfort, in which >=4 of following developed abruptly and reached a peak within 10 mins:
1. Palpitations
2. Sweating
3. Trembling / Shaking
4. Sensations of SOB
5. Feeling of choking
6. Chest pain / discomfort
Etc.

Recurrent unexpected attacks for >=1 month

Question 17

Feeding and Eating Disorders

Answer 17

1. Anorexia nervosa (significantly low BMI and fat phobia)
2. Bulimia nervosa (repeated binge eating and fat phobia)
3. Binge-eating disorder
4. Pica
5. Rumination disorder (regurgitation of food)
6. Avoidant / Restrictive food intake disorder
7. OS / US feeding and eating disorder

Question 18

Diagnostic criteria for Anorexia nervosa

Answer 18

• Restriction of energy intake relative to requirements
  —> significantly low BW
• Intense fear of gaining weight / becoming fat / persistent behaviour that interferes with weight gain
• Disturbance in the way which BW / shape is experienced, undue influence of BW / shape on self-evaluation / persistent lack of recognition of seriousness of current low BW
• ***3 months
• Mild BMI >=17, Moderate 16-16.99, Severe 15-15.99, Extreme <15
• Restricting and binge-eating / purging type

Question 19

Sleep-wake Disorders

Answer 19

6 major types
1. Insomnia disorder
2. Parasomnias (e.g. sleepwalking)
3. Hypersomnolence disorder / Narcolepsy
4. Circadian rhythm sleep-wake disorder (e.g. delayed sleep-wake phase)
5. Breathing-related sleep disorders (e.g. OSAS)
6. Movement-related sleep disorders —> Restless leg syndrome / PLMD
(- Substance / medication-induced)
(- OS / US sleep-wake disorders)

Question 20

Diagnostic criteria for Insomnia disorder

Answer 20

• Predominant complaint of dissatisfaction with sleep quantity / quality
  —> >=1 difficulty initiating sleep
  —> difficulty maintaining sleep
  —> early morning awakening
• Clinically significant distress / impairment in functioning
• **>=3 nights per week for **>=3 months
• Despite adequate opportunity for sleep
• Not better explained by other sleep disorder, substance use, mental, medical conditions

Primary / Comorbid insomnia

Question 21

Diagnostic criteria for Autism Spectrum Disorder

Answer 21

• Persistent deficits in social communication and social interaction across multiple contexts
• Restricted, repetitive patterns of behaviour, interests / activities
• Present since childhood
• Impairment in functioning
• Not better explained by intellectual disability / developmental delay

Question 22

Diagnostic criteria for ADHD

Answer 22

• Persistent pattern of **Inattention / **Hyperactivity-impulsivity
• Present prior to ***age 12
• > =2 settings
• Impairment in functioning
• Not occur exclusively during other disorders

Question 23

Disruptive, Impulse-control, Conduct disorders

Answer 23

• Intermittent explosive disorder
• Oppositional defiant disorder
• Conduct disorder
• Antisocial personality disorder
• Kleptomania (stealing)
• Pyromania (fire setting)
• OS / US impulse control disorder

Question 24

Personality disorders

Answer 24

Cluster A (Strange type):
- Paranoid, Schizoid, Schizotypal

Cluster B (Emotional type):
- Antisocial, Borderline, Histrionic, Narcissitic

Cluster C (Anxious type):
- Avoidant, Dependent, Obsessive-compulsive

Question 25

Diagnostic criteria for Borderline Personality Disorder

Answer 25

Pervasive pattern of instability of interpersonal relationships, self-image and affects and marked impulsivity, beginning by early adulthood and present in a variety of contexts, as indicated by 5 or more of following: - Frantic efforts to ***avoid real / imagined abandonment - Pattern of ***unstable / intense interpersonal relationship, alternating between extremes of idealisation and devaluation - ***Identity disturbance: unstable self image / sense of self - ***Affective instability - ***Chronic feelings of emptiness Etc.

Question 26

Diagnostic criteria for Major Neurocognitive Disorder (Dementia)

Answer 26

- Significant cognitive decline from a previous level of performance in ***>=1 domains (complex attention, executive function, learning and memory, language, perceptual-motor, social cognition) based on informants / cognitive tests - Interfere with independent living - Not better explained by other mental disorder