Somatic Symptom and Related Disorders

Somatic Symptom Disorder (Old: Somatisation Disorder)

DSM-5 criteria – ALL must be met: ^[Ref]

1. ≥1 distressing somatic symptom causing significant disruption to daily life
   • Examples include pain, fatigue, dizziness, gastrointestinal symptoms, palpitations or weakness
2. Excessive thoughts, anxiety or behaviour related to the symptom(s), with at least 1 of the following:
   • Disproportionate and persistent thoughts about the seriousness of the symptoms
   • Persistently high health-related anxiety
   • Excessive time and energy devoted to the symptoms or health concerns
3. Persistent symptoms, lasting >6 months

Illness Anxiety Disorder (Old: Hypochondriasis)

DSM-5 criteria – ALL must be met: ^[Ref]

1. Persistent worry about having or developing a serious illness (e.g. cancer,
2. Absent or mild somatic symptoms
   • If a genuine medical condition or symptoms are present, the level of concern is clearly excessive or disproportionate
3. High health-related anxiety (easily alarmed by normal sensations or minor symptoms)
4. Excessive health-related behaviour or avoidance
   • Examples: repeated body checking, repeated reassurance-seeking, frequent medical appointments
   • Or conversely, avoiding doctors, hospitals or investigations because of fear
5. Persistent worrying for ≥6 months
6. Not better explained by another mental disorder

Functional Neurological Disorder (Old: Conversion Disorder)

DSM-5 criteria – ALL must be met: ^[Ref]

1. ≥1 neurological sign / symptom affecting voluntary motor OR sensory function
   • Motor examples: weakness, abnormal movements, gait disturbance, non-epileptic seizures
   • Sensory examples: sensory loss, paraesthesia, visual symptoms
2. Incompatible with a recognised neurological / medical condition (see below for +ve clinical signs)
3. Not better explained by another medical or mental disorder
4. Symptom or deficit results in clinically significant distress or impairment

Other features: ^[Ref]

• Signs / symptoms are NOT intentionally produced
• “La belle indifference” – patient may show an apparent lack of concern about significant symptoms
  • NB this is NOT specific and NOT required for diagnosis

Functional neurological disorder is NOT simply a diagnosis of exclusion, it should be supported by positive signs of incompatibility with recognised neurological disease, including: ^[Ref]

• Hoover’s sign
• Collapsing weakness
• Distractibility
• Non-dermatomal loss (often presenting with a sharp, unnatural demarcation at a joint line)
• Arm drop test
• Sternocleidomastoid test

Factitious Disorder

Factitious disorder involves: ^[Ref]

• Intentional falsification / production of illness
• With NO obvious external gain / incentive
• The behaviour is not better explained by another mental disorder

There are 2 forms: ^[Ref]

1. Factitious disorder imposed on self
   • The person deliberately falsifies, exaggerates or induces signs / symptoms in themselves
   • They present themselves to others as ill, injured or impaired
2. Factitious disorder imposed on another (Munchausen syndrome by proxy)
   • The person deliberately falsifies, exaggerates or induces signs / symptoms on another person 
   • They present the other person to others as ill, injured or impaired
   • The victim is often a child or dependent adult
   • The psychiatric diagnosis applies to the perpetrator, not the victim

Common methods of symptom falsification: ^[Ref]

• Ingesting toxic substances (e.g. spoiled food, chemicals)
• Injecting medications (e.g. injecting insulin to induce hypoglycaemia)
• Self-inflicted injury (e.g. interfering with wound healing)
• Tampering with investigations (e.g. altering laboratory samples)
• Falsifying medical history or documentation

Malingering

Malingering involves intentional fabrication, exaggeration or production of illness (physical or psychological symptoms) for an external incentive (secondary gain) ^[Ref]

• Signs / symptoms are consciously and deliberately produced
• There is a clear secondary gain, such as:
  • Financial compensation
  • Obtaining drugs
  • Avoiding work, school or military service
  • Avoiding legal consequences
  • Obtaining housing or another practical benefit
• Features that should raise suspicion of malingering include
  • Marked discrepancy between reported symptoms / disability and objective findings
  • Lack of cooperation with assessment or treatment
  • Presentation in a medicolegal context (e.g. self-referred or referred by an attorney with pending litigation, legal claims, or criminal charges)
  • Presence of antisocial personality disorder