The evaluation of any patient with epilepsy and psychiatric symptoms must include:
- a careful evaluation of the seizure disorder and any other neurologic disorders
- a complete medical history, with a description of past and concurrent medical comorbidities
- a detailed family history to identify any genetic risk factors for neurologic, medical, or psychiatric disorders
- an assessment of the patient's social status, including occupation, marital status, and educational history
This discussion will focus specifically on the important steps in the evaluation of psychiatric symptoms or disorders in patients with epilepsy.
Most important, any initial evaluation of patients with epilepsy cannot be complete unless it includes an investigation of the presence of psychiatric symptoms or disorders and cognitive disturbances. The patient and family members should describe the impact (if any) that the seizure disorder had on the patient's quality of life at a social, professional, and familial level.
At the least, clinicians need to ask about the presence of symptoms of depression and anxiety in adult patients, as these are the most frequently reported psychiatric symptoms in adults with epilepsy. Clinicians need to ask whether children have shown impulsive behavior, motor hyperactivity, poor frustration tolerance, problems with concentration, or academic difficulties.
In the evaluation of patients with epilepsy and psychiatric symptoms, it is essential to establish the type of seizures and epilepsy syndrome and the cause of the seizure disorder, if it can be established. Certain epilepsy syndromes are more likely to be associated with certain psychiatric disorders.
It is also important to have a careful description of the type of antiepileptic drugs (AEDs) the patient has taken, the response to these AEDs with respect to seizure control and adverse events, and the course of the seizure disorder over the years.
A careful psychiatric history is also essential, including a detailed description of signs and symptoms, their course over time, circumstances that resulted in an exacerbation or remission, and response to any treatment.
A careful psychiatric family history also should be obtained, because a history of mood or anxiety disorder in a first-degree relative constitutes a strong risk factor for the development of these psychiatric disorders.
The answers to several questions determine whether the seizure disorder or its treatment are directly related to the development of the psychiatric symptoms:
- Was there a temporal relationship between the onset of psychiatric symptoms (when first identified by the patient or family) and the onset of the seizure disorder? Patients and family members often can remember noticing a change in mood or the presence of irritability a few weeks or months after the first seizure.
- Was there a temporal relationship between the onset of psychiatric symptoms and the introduction, dose change, or withdrawal of an AED? Psychiatric symptoms can represent side effects of AEDs, in which case dose reduction or discontinuation of the new AED should result in symptom remission. Also, several AEDs have mood-stabilizing properties. Their discontinuation may have unmasked an underlying mood disorder. In these cases, reintroduction of the AED or another AED with mood-stabilizing properties may lead to symptom remission.
- Is there a temporal relationship between the timing of symptoms and seizure occurrence? The answer to this question will allow the clinician to determine whether the symptoms are pre-ictal, ictal, postictal, or interictal. It is important to remember, however, that interictal symptoms may be exacerbated during the postictal period.
- Was the onset of the psychiatric symptoms related to a change in seizure type or frequency? For example, a de novo postictal psychosis can occur in a patient who used to have only complex partial seizures but started experiencing clusters of generalized convulsions after a change of AED.
- Is there a family history (especially in first-degree relatives) of psychiatric disorders, particularly mood, anxiety, or attention deficit disorders? Such a family history constitutes an important risk factor for the development of these psychiatric disorders, and certain AEDs can bring them to the surface. For example, phenobarbital or primidone can increase the risk of depression significantly when given to patients with a family history of mood disorders.
If the patient has a personal psychiatric history that precedes the onset of the seizure disorder, the clinician needs to inquire about the following:
- the impact of seizures on the psychiatric symptoms
- the impact of AED treatment on the psychiatric symptoms
- whether treatment of the psychiatric disorder was suspended or modified because of concern about negative impact on their seizures
- the impact of psychiatric symptoms on seizure occurrence (for example, do seizures tend to increase in the midst of a recurrence of depression or panic disorder?)
Psychiatric disorders are under-recognized and under-treated in patients with epilepsy because patients are reluctant to report their seizures and symptoms to their treating physicians and the physicians fail to inquire about them. The result is that epilepsy is complicated by the presence of psychiatric disorders that often take a greater toll on the quality of life than the seizures. It is the responsibility of both patient and physician to ensure that this does not happen!
Adapted from: Holzer JC and Bear DM. Psychiatric considerations in patients with epilepsy. In: Schachter SC, Schomer DL, eds. The comprehensive evaluation and treatment of epilepsy. San Diego, CA: Academic Press; 1997. p. 131-148. With permission from Elsevier (www.elsevier.com).