Dissociative Seizures

Question 1

What are differential diagnoses of dissociative seizures?

Answer 1

Syncope
Epilepsy
Metabolic/endocrine
Factitious disorder
Other psychiatric presentations mistaken for epilepsy

Question 2

How does ICD 11 categorise dissociative seizures?

Answer 2

Dissociative neurological symptom disorder with non-epileptic seizures

Question 3

What percentage of people with DS have comorbid epilepsy?

Answer 3

15%

Question 4

What proportion of people presenting with first fit don’t have epilepsy?

Answer 4

1 in 7

Question 5

What is the typical age of onset for dissociative seizures?

Answer 5

Teens or early twenties

Question 6

What are the consequences of misdiagnosis of DS as epilepsy?

Answer 6

Missed opportunity of DS treatment
Multiple trials of AEDs
Being mistaken for status epilepticus

Question 7

What are potential consequences of DS being mistaken for status epilepticus?

Answer 7

Admittance to ICU
Sedation with benzodiazepines
Ventilation

Question 8

What features are common in DS but rare in ES?

Answer 8

Over 2 mins duration
Awareness without responsiveness
Closed eyes
Fluctuations course
Asynchronous movements
Side to side head movement
Pelvic thrusting
Weeping
Opisthotonus
Thrashing

Question 9

What features favour epilepsy over DS?

Answer 9

Stertorous breathing (snoring type sound)
Post ictal confusion
Automatisms

Question 10

What features of a seizure are not helpful in distinguishing DS and ES?

Answer 10

Urinary incontinence
Injury
Tongue biting
Mouth biting
Reported seizures from sleep

Question 11

Why is status epilepticus a medical emergency?

Answer 11

Prolonged seizure can engender anoxic brain injury

Question 12

What are the panic related phenomena of DS?

Answer 12

Derealisation
Panic attack symptoms
-Palpitations
-Sweating
-Hyperventilation
-Paraesthesia
-Dry mouth
Emotional relief after

Question 13

What features might be supportive of a DS diagnosis?

Answer 13

Failed response to AEDs
Family history
CNS infectiond
Mild/moderate developmental problems
Previous medically unexplained symptoms
Past psychiatric history
Childhood trauma

Question 14

What are features on EEG indicative of DS?

Answer 14

Preserved alpha rhythm (awake with eyes closed)

Question 15

What are features on EEG indicative of epilepsy?

Answer 15

Ictal epileptiform discharges
Post-ictal slowing

Question 16

What might be a false positive on EEG?

Answer 16

Movement artefact

Question 17

What might be a false negative on EEG?

Answer 17

Simple partial seizure
Frontal lobe seizure

Question 18

What is the sensitivity to epilepsy of EEG seizure provocation?

Answer 18

63-92%

Question 19

What should psychiatric assessment look for when distinguishing between DS and ES?

Answer 19

Primary psychiatric disorder mistaken for epilepsy
Associated psychiatric disorder
Deliberate simulation (rare, do not focus)
Predisposing, precipitating, perpetuating factors

Question 20

How do panic attacks and ictal anxiety differ?

Answer 20

-ictal anxiety “feels different” to typical anxiety
-situational triggers are rare
-irrational fears are rare (seizure phobia exists)

Question 21

What is the rate of psychiatric disorders in DS?

Answer 21

Very high

Personality disorder 30-60%
Somatoform disorder 30-80%
Depression 25-60%
Anxiety 20-50%
PTSD 38%

Question 22

What are predisposing factors for DS?

Answer 22

Psychobiological

Somatising trait
Dissociative trait
Avoidant coping
Emotional insta ikity
Mood disorder
Epilepsy

Social
Traumatic experiences
Dysfunctional family
Modelling of symptoms

Question 23

What are the maintaining factors of DS?

Answer 23

Sick role
Attitude of carers
Illness beliefs
Agoraphobia
Reaction to diagnosis

Question 24

What is the psychological model for DS?

Answer 24

Panic release
Psych cue - arousal-dissociation-relief