ABSTRACT
Through observation and scientific investigation spanning well over a century, physicians treating people with epilepsy have assembled substantial evidence confirming crucial links between sleep and epilepsy. Seizure occurrence in several forms of epilepsy is tightly regulated by the sleep-wake cycle, with seizures occurring predominately or exclusively from sleep or on awakening. Non-rapid eye movement (NREM) sleep facilitates while rapid eye movement (REM) sleep inhibits seizure occurrence. Sleep and sleep deprivation not only provoke seizures but also activate epileptiform activity. More recently, investigations using video-electroencephalographic (videoEEG) monitoring and polysomnography (PSG) have shown that seizures, antiepileptic drugs (AEDs), primary sleep disorders, and perhaps certain epilepsies affect sleep and wakefulness in people with epilepsy. Although the focus of this chapter is AED therapy, we begin with a brief discussion of these other factors that contribute to sleep and wake disturbances in epilepsy.
Excessive daytime sleepiness (EDS) is one of the most common complaints among people with epilepsy, typically attributed to the effects of AEDs and seizures. An estimated one-third to one-half of people with epilepsy report EDS.1-4 In larger series, 11-28% of epilepsy patients had Epworth Sleepiness Scale (ESS) scores >10, suggesting EDS.5-7 Surprisingly few studies have used objective measures of EDS, such as the Multiple Sleep Latency Test (MSLT). Among 30 patients with epilepsy on AED therapy administered the MSLT, the mean sleep latency (MSL) was 8.4 minutes, suggesting the presence of borderline hypersomnia.8 More recently, another study of 42 patients with refractory epilepsy and comorbid obstructive sleep apnea (OSA) also found a borderline MSL of 8.4 minutes for the group overall, but one-third of subjects had MSLs of <5 minutes, suggesting a more significant
