Page 161 - ILAE_Lectures_2015

Chapter 16

Psychiatric disorders in epilepsy

JACQUELINE FOONG

Department of Neuropsychiatry, National Hospital for Neurology and Neurosurgery, Queen
Square, London

Studies have estimated that up to 50% of patients with epilepsy develop psychiatric disorders,
the most common being depression, anxiety and psychotic disturbances1. These psychiatric
disturbances can be classified according to how they relate in time to seizure occurrence, i.e.
ictal, peri-ictal (pre-ictal/prodromal, post-ictal) or inter-ictal. Multiple risk factors are
associated with the increased risk of psychiatric problems in epilepsy which can be broadly
divided into biological (e.g. type and severity of epilepsy), psychosocial and iatrogenic
(antiepileptic drugs, surgery).

Ictal

Mood and behavioural changes can occur as direct manifestation of the seizures, including
anxiety, depression, hallucinations. The episodes are usually brief (<13 minutes),
stereotyped, begin and end abruptly, and can be associated with other ictal phenomena (oral,
motor automatisms). They usually occur with partial seizures, simple partial (aura) or
complex partial seizures but can also occur in generalised seizures.

Ictal anxiety is common, with up to one-third of patients with partial seizures reporting fear
as part of their aura, usually in patients with right temporal foci.

Ictal depression occurs less frequently than ictal anxiety and common symptoms are guilt,
hopelessness, worthlessness, and suicidal ideation.

Ictal psychotic symptoms can manifest as visual, gustatory or auditory hallucinations and are
usually not well defined. They are mainly associated with partial seizures.

Ictal aggression is very rare and mostly involves undirected or unintentional violence.

The treatment of ictal psychiatric disturbances is aimed at adequate seizure control. During
an episode, maintaining the patient’s safety is the primary concern. Educating patients and
their families about the psychiatric manifestations is also important.

Peri-ictal

Pre-ictal or prodromal mood changes usually manifest as irritability, lability, depression,
anxiety or aggression and are relieved by the seizure. These symptoms can last a few hours,
and sometimes up to a few days before a seizure.

Post-ictal psychiatric disturbances are more likely to occur following clusters of seizures,
generalised seizures or status epilepticus.

Post-ictal confusion is characterised by impaired awareness/consciousness and diffuse EEG
slowing without ictal discharges. These episodes are usually brief and common after complex