Neuropsychiatric Symptoms of Epilepsy

2 Depression
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atypical clinical manifestations and fail to meet the diagnostic criteria included in
the Diagnostic and Statistical Manual of Mental Disorders-IV ( DSM-IV ) [ 31 ]. They
consist of symptoms of depression intermixed with brief euphoric mood, irritability,
anxiety, paranoid feelings, and somatic symptoms (anergia, atypical pain, and
insomnia). They tend to follow a chronic course with recurrent symptom-free periods.
This type of depression had been recognized since the beginning of the twentieth
century [ 32 ], and in later years was referred as “Interictal Dysphoric Disorder of
Epilepsy” [ 33 ]. Yet, Mula et al. demonstrated that this form of depression was not
specific to PWE [ 34 ].
Depressive and anxiety disorders often occur together. For example, in a study of
188 consecutive PWE, 31 met DSM-IV criteria of a current major depressive episode.
Twenty-one of these patients had a mixed MDE and an anxiety disorder [ 35 ].
Recognition of such comorbidity is of the essence, as failure to target the anxiety
symptomatology in the treatment plan can result in the recurrence of the depressive
disorder. In addition, comorbid depressive and anxiety disorders in patients with
and without epilepsy are associated with a worse course of the depressive disorder
and a worse quality of life than in patients with only the depressive disorder [ 35 ].
Clinical Manifestations of Depressive Episodes Particular
to Epilepsy
Depressive episodes and symptoms of depression in PWE can follow a temporal
relation to the occurrence of seizures and present before (pre-ictal), as an expression
of the ictus (ictal), after the seizure (postictal), or may be independent of the timing
of the seizure occurrence (interictal). In addition, depressive episodes can be the
expression of a “para-ictal” disorder, which occurs upon the sudden remission of
seizures in patients with treatment-resistant epilepsy.
Pre-ictal symptoms of depression and depressive episodes typically present as a
dysphoric mood in which the prodromal symptoms may extend for hours or even
1–3 days prior to the onset of a seizure. This was exemplified by Blanchet and
Frommer [ 36 ] who assessed mood changes during the course of 56 days in 27 PWE,
who rated their mood on a daily basis. Mood ratings pointed to a dysphoric state 3
days prior to a seizure in 22 (81 %) patients. This change in mood was greatest during
the 24 h preceding the seizure. Patients or parents of children with epilepsy
often report that dysphoric symptoms completely resolve the day after the ictus.
Ictal symptoms of depression are the clinical expression of a focal seizure without
loss of consciousness in which the depressive symptoms are the sole (or
predominant) semiology and in which the symptomatogenic zone involves limbic
structures, in particular, in mesial temporal regions. The actual prevalence of ictal
symptoms of depression is yet to be established in larger studies. Symptoms of
depression ranked second after symptoms of anxiety/fear as the most common type
of ictal affect in one study [ 37 ]. This presentation occurred in 21 % of 100 PWE
who reported auras consisting of psychiatric symptoms [ 38 , 39 ]. The most frequent