Neuropsychiatric Symptoms of Epilepsy

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Table 17.2 Risk factors for depressive symptoms after adult epilepsy surgery [ 24 , 26 , 27 , 29 , 37 ,
50 , 53 , 54 , 58 , 59 , 62 – 68 ]
Neurobiological antecedents
Bilateral EEG abnormalities
Anhoury et al. [ 62 ]; Carran et al. [ 53 ]; de
Araújo Filho et al. [ 29 ]
Larger resection Anhoury et al. [ 62 ]
Secondarily generalized seizures Cleary et al. [ 63 ]; Carran et al. [ 53 ]
More frequent seizures presurgery Desai et al. [ 27 ]
Abnormal contralateral hippocampal volume Paparrigopoulos et al. [ 64 ]; Wrench et al. [ 58 ]
Younger age at surgery Moss et al. [ 37 ]
Psychiatric and psychosocial antecedents
High neuroticism and low extraversion Wilson et al. [ 65 ]
Preoperative personality disorder [PD], chiefly Koch-Stoeker [ 66 ]
Cluster C (Avoidant, Dependent, or Obsessive-
Compulsive PD) or Cluster B (Borderline,
Antisocial, Histrionic, or Narcissistic PD)
Preoperative psychiatric history
Malmgren et al. [ 24 ]; Quigg et al. [ 67 ]; Pintor
et al. [ 68 ]; Wrench et al. [ 50 ]; Cleary et al.
[ 26 , 63 ]; de Araújo Filho et al. [ 29 ]
Poor postoperative family dynamics Wrench et al. [ 50 ]
Difficulties adjusting to changed roles post Meador [ 54 ]; Wilson et al. [ 59 ]
surgery
adapting to new societal and family roles, and poor postoperative family dynamics.
Most consistently, however, a preexisting psychiatric history is reported, with studies
from psychiatric populations supporting the notion that cumulative disruption to
brain structure, function, and cognitive processing from previous depressive episodes
heightens the risk of symptom recurrence in the future [ 61 ].
Neurobiological risk factors for postoperative depression include bilateral EEG
abnormalities in presurgical investigations, younger age at surgery, a larger
resection, preoperative generalized seizures, more frequent preoperative seizures,
and abnormal hippocampal volume in the contralateral hemisphere (Table 17.2 ).
While it appears that postsurgical depression is not related to the histopathology of
the epileptogenic lesion [ 24 , 56 , 62 , 69 ], there is considerable ambiguity as to
whether the laterality of the lesion is an important antecedent, with no compelling
evidence either way: some studies show no effect of laterality [ 24 , 32 , 56 , 62 ], while
others suggest that a right-sided resection is a vulnerability factor for worsening
mood after surgery [ 23 , 37 , 53 , 67 ]. Overall, the neurobiological risk factors for
depression after epilepsy surgery comprise markers of more chronic, severe, and
widespread epileptogenic abnormality occurring alongside focal unilateral dysfunction
in mesial temporal structures.
Finally, specific risk factors for persistent depressive symptoms at 24-months
include older age, preoperative generalized seizures, a family history of seizures, as
well as a family history of psychiatric illness [ 32 ]. The relationship between a family
history of psychiatric disturbance and persistent depression is particularly note-