Neuropsychiatric Symptoms of Epilepsy

132
P. Tinuper et al.
been postulated to be the reason whereby treatment of a sleep disorder improves
seizure control, even if the exact mechanism is unknown [ 86 ].
The majority of sleep disorders do not need pharmacological treatment.
Behavioral therapy and regular and regularization of sleep habits may reduce the
problem in most cases [ 2 ].
On the other hand, sleep problems in young children may present with hyperactivity
or behavioral problems rather than excessive somnolence. Recognition of the
paradoxical response of hyperactivity as the result of excessive daytime sleepiness
is central to evaluation of these pediatric patients [ 2 ].
Insomnia has been reported in patients with epilepsy and may be caused by different
situations. In particular, patients with epilepsy may become disabled, which
will lead to “behaviorally” induced circadian rhythm problems because they may
choose their own sleep hours if inactive. Nighttime fears may affect patients with
epilepsy as well, especially if they have nocturnal seizures. In addition, caregivers
may feel anxious about leaving the patient alone in the room [ 87 ].
How Treatment of Seizures Affects Sleep
Not only seizures but also antiepileptic drugs (AEDs) may contribute to sleep disorders
and adversely affect sleep. For example, in a patient predisposed to OSA, barbiturates
and benzodiazepines may worsen the frequency of apneas and hypopneas
by reducing the muscle tone of the upper airways and increasing the arousal threshold.
Similarly AEDs that are associated with weight gain (i.e., VPA) may worsen
OSA. Avoiding these agents in patients with untreated OSA may be advisable, especially
if alternative AEDs are available.
Clinicians may base their AED choice not only on the epilepsy syndrome but
also on its effects on coexisting sleep disorders and complaints [ 2 ]. Somnolence and
diurnal sedation are the most common side effects of AEDs especially in patients on
polytherapy [ 86 , 88 ]. Whether it is epilepsy itself or AEDs which cause abnormal
sleep architecture is difficult to determine. This adverse effect on sleep is especially
relevant to the AED effect on cognitive functions. It is likely that cognitive effects
of AEDs on memory and concentration are related to drug effects on the central
nervous system mediating arousal rather than the specific effect on cognitive functions.
Ideally the AED chosen to treat epilepsy should have the least effect on sleep.
This may not be always possible.
AEDs have been shown to have a variety of effects on sleep and daytime vigilance.
However, the literature is confounded by significant methodological variations across
studies, including composition of the study population, dose, timing and duration of
treatment, and failure to control for seizures and concomitant AEDs. Much of the
available literature on the older AEDs comes from animal studies, but with the use of
newer anticonvulsants in other neurologic and psychiatric conditions, new data are
becoming available on patients exposed to AEDs for the first time.
It has been shown that anticonvulsants can improve seizure control by stabilizing
sleep [ 15 , 89 ]. Although it is certainly possible that part of the improved sleep seen