Dissociative Seizures Flashcards
What are differential diagnoses of dissociative seizures?
Syncope
Epilepsy
Metabolic/endocrine
Factitious disorder
Other psychiatric presentations mistaken for epilepsy
How does ICD 11 categorise dissociative seizures?
Dissociative neurological symptom disorder with non-epileptic seizures
What percentage of people with DS have comorbid epilepsy?
15%
What proportion of people presenting with first fit don’t have epilepsy?
1 in 7
What is the typical age of onset for dissociative seizures?
Teens or early twenties
What are the consequences of misdiagnosis of DS as epilepsy?
Missed opportunity of DS treatment
Multiple trials of AEDs
Being mistaken for status epilepticus
What are potential consequences of DS being mistaken for status epilepticus?
Admittance to ICU
Sedation with benzodiazepines
Ventilation
What features are common in DS but rare in ES?
Over 2 mins duration
Awareness without responsiveness
Closed eyes
Fluctuations course
Asynchronous movements
Side to side head movement
Pelvic thrusting
Weeping
Opisthotonus
Thrashing
What features favour epilepsy over DS?
Stertorous breathing (snoring type sound)
Post ictal confusion
Automatisms
What features of a seizure are not helpful in distinguishing DS and ES?
Urinary incontinence
Injury
Tongue biting
Mouth biting
Reported seizures from sleep
Why is status epilepticus a medical emergency?
Prolonged seizure can engender anoxic brain injury
What are the panic related phenomena of DS?
Derealisation
Panic attack symptoms
-Palpitations
-Sweating
-Hyperventilation
-Paraesthesia
-Dry mouth
Emotional relief after
What features might be supportive of a DS diagnosis?
Failed response to AEDs
Family history
CNS infectiond
Mild/moderate developmental problems
Previous medically unexplained symptoms
Past psychiatric history
Childhood trauma
What are features on EEG indicative of DS?
Preserved alpha rhythm (awake with eyes closed)
What are features on EEG indicative of epilepsy?
Ictal epileptiform discharges
Post-ictal slowing
What might be a false positive on EEG?
Movement artefact
What might be a false negative on EEG?
Simple partial seizure
Frontal lobe seizure
What is the sensitivity to epilepsy of EEG seizure provocation?
63-92%
What should psychiatric assessment look for when distinguishing between DS and ES?
Primary psychiatric disorder mistaken for epilepsy
Associated psychiatric disorder
Deliberate simulation (rare, do not focus)
Predisposing, precipitating, perpetuating factors
How do panic attacks and ictal anxiety differ?
-ictal anxiety “feels different” to typical anxiety
-situational triggers are rare
-irrational fears are rare (seizure phobia exists)
What is the rate of psychiatric disorders in DS?
Very high
Personality disorder 30-60%
Somatoform disorder 30-80%
Depression 25-60%
Anxiety 20-50%
PTSD 38%
What are predisposing factors for DS?
Psychobiological
Somatising trait
Dissociative trait
Avoidant coping
Emotional insta ikity
Mood disorder
Epilepsy
Social
Traumatic experiences
Dysfunctional family
Modelling of symptoms
What are the maintaining factors of DS?
Sick role
Attitude of carers
Illness beliefs
Agoraphobia
Reaction to diagnosis
What is the psychological model for DS?
Panic release
Psych cue - arousal-dissociation-relief
