A2zzz_vol18num4.pdf

EPILEPSY: THE NIGHT THIEFBy Mary Ellen Wells, MS, RPSGT, REEGT, RNCST Sleep is vital to the health and well-being of all people but follows a cyclical pattern, and in certain conditions it may be takes on new meaning for patients with epilepsy. People with predominately nocturnal. The human circadian rhythm also has epilepsy are commonly referred to a sleep laboratory because of a cyclical pattern and oscillates between wake and sleep, and disrupted sleep. Daytime sleepiness and insomnia are frequent sleep oscillates between non-rapid eye movement (NREM) sleep symptoms experienced by patients with epilepsy.1 Other reported and REM sleep. Epileptic activity is influenced by sleep stages. symptoms include poor cognitive performance, memory dysfunc- In some idiopathic epilepsies, NREM sleep physiologic oscilla- tion and sleep related breathing issues. Frequently, these symp- tions and epileptic seizures are generated by the same cerebral toms are attributed to medications or the underlying seizure circuitry. Epileptiform activity is facilitated during NREM sleep, disorder; an underlying sleep disorder is often missed.
and partially inhibited during REM sleep. Certain epileptic An increase in health problems occurs as a result of untreated syndromes produce seizures almost exclusively during sleep (e.g., sleep disorders across all people, but people with epilepsy can frontal lobe epilepsy), and some produce seizures almost exclu- experience additional devastating effects. There is a clear connec- sively upon awakening (e.g., juvenile myoclonic epilepsy). Sleep tion between seizures and sleep. Disruption of sleep can increase architecture is likewise influenced by epileptic activity. Effects seizure frequency and severity, particularly in can include an increase in sleep latency, increase the case of sleep-disordered breathing. Many in number and duration of awakenings, decrease medications used to treat seizure disorders have in sleep efficiency, and reduction or fragmenta- adverse effects on sleep, which is further intensi- fied when a sleep disorder exists and is untreated. All of these effects may lead to uncontrolled epilepsy and severe disability. It is important to Seizures are primarily classified by the area of note that most of the sleep disorders occurring in the brain involved. Many factors are involved in conjunction with epilepsy are treatable. determining the causes of seizures; causes may vary depending on age, gender and related medi- cal conditions. It is important to identify the Approximately three million people in the U.S. seizure type, primarily because it may affect the have epilepsy, and 200,000 new cases of epilepsy are diagnosed each year, according to the Na- tional Epilepsy Foundation. A seizure is defined Seizures are typically classified in two primary as “an electrical brainstorm” or abnormal electri- groups: partial and generalized. Partial seizures cal activity in the brain with an underlying cause, affect only a part of the brain at onset. General- which elicits some change in activity or behavior. ized seizures are widespread and involve both Epilepsy is defined as a disorder in which a cerebral hemispheres simultaneously. Partial person has a predisposition to having seizures. seizures may spread to become generalized, just Rather than being considered a disease, epilepsy as a single spark can light a fire. Partial seizures is mainly viewed as a symptom of a disease. are further broken into categories of simple and Although there are numerous causes of epilepsy complex; simple seizures do not alter alertness, such as a tumor, trauma, infection, and a genetic whereas complex seizures do have an impact on disorder, the cause of many cases of epilepsy is consciousness. The following list is a classifica- unknown.2 There are many types of epilepsy syndromes, which have specific seizure types as well as associated symptoms. Simple Partial Seizures
As early as the late 1800s, studies demonstrated the strong These seizures do not impair consciousness and often begin in correlation between sleep and seizures. Epileptiform activity the temporal or frontal lobe. Simple partial seizures are classified according to the following characteristics: ▪ Motor signs, including postural, versive and phonatory Somatosensory or special sensory signs, including simple RNCST, has been in the sleep field since hallucinations such as tingling, buzzing sounds and flashes of 1999 and is a clinical assistant professor Autonomic signs or symptoms, including sweating, flushing ences at the University of North Carolina Psychic symptoms, including déjà vu; cognitive and affective impairments, such as time distortion, fear, and anger; and structured hallucinations, such as music and scenes Complex Partial Seizures
Atonic or Akinetic Seizures
These seizures impair consciousness and often begin in the A “drop attack” is the term often used to describe an atonic temporal or frontal lobe. They also may begin as simple partial seizure, because the event involves a fall without warning. These seizures (the aura) and evolve to complex partial seizures. Com- seizures last less than 15 seconds and involve the sudden loss of plex partial seizures are classified according to these signs and muscle tone. Manifestations may include facial drooping, drop- ping objects and falling. Patients who suffer from these episodes often require helmets or other protection to prevent injury.
▪ Impairment of consciousness upon seizure onset ▪ Simple partial seizure onset with evolvement to complex partial seizure. Symptoms include those of simple partial Seizures occur most frequently during stage 2 sleep, but they seizures as listed above, followed by impairment of also occur during drowsiness and slow wave sleep; they rarely consciousness. Symptoms also may include automatisms occur during REM sleep. Many studies have demonstrated that (involuntary and purposeless movements), followed by sleep deprivation causes an increase in seizure frequency. Sleep continuity is disrupted, and daytime sleepiness with increased seizures may occur when nocturnal seizures are more frequent. It Partial Seizures Evolving into Secondarily Generalized
is also noted that people with epilepsy have a higher incidence of Seizures
parasomnias, nighttime awakenings, longer sleep latency, daytime These seizures occur in three forms, with symptoms described above. The onset can be a simple partial or complex partial seizure that evolves to a generalized seizure. Or, onset may be a simple partial seizure evolving to a complex partial seizure, and Many people with epilepsy are concurrently affected by sleep finally evolving to a generalized seizure.
disorders. The relationship between epilepsy and sleep disorders is often misunderstood and may lead to inadequate treatment or misdiagnosis if not carefully investigated. Whether they occur at Absence Seizures
night or during the day, seizures cause sleep disturbances. Many Typical absence seizures begin and end abruptly, typically studies show increases in sleep complaints from people with epi- lasting from five to 20 seconds and rarely longer than one to lepsy. Disruptions of the parts of the brain involved in regulating two minutes. Children older than four years of age are primarily sleep and how the person is able to recognize and differentiate affected; however, seizures rarely persist into adulthood. Ab- their related sleep and/or wake symptoms may be responsible sence seizures impair consciousness and may occur many times for some of the increase in sleep complaints by persons with epi- a day. They can occur alone, or may include automatisms, atonic lepsy.1 The hypnogram of patients with seizures typically reveals symptoms, clonic symptoms, and/or autonomic symptoms. Often fragmented sleep.6 Sleep deprivation resulting from sleep disor- the patient will stare blankly, and eye fluttering or eyes rolling ders increases the occurrence of seizures in patients with seizure upward may be observed. Posture is often maintained. Typically disorders and may cause deterioration of seizure control.7,8 the person will have no recollection of the event. NREM sleep When sleep disorders are properly diagnosed and treated and hyperventilation are facilitators of absence seizures. Often in patients with epilepsy, increased seizure control is usually school-aged children with absence seizures are misdiagnosed achieved, and quality of life is significantly improved. In a study with attention and behavioral problems.
of 63 epilepsy patients with sleep disorders, 78 percent were referred for obstructive sleep apnea with 71 percent achiev- Myoclonic Seizures
ing a positive diagnosis.8 In this study, diagnoses of narcolepsy, Myoclonic seizures are characterized by rapid, involuntary insufficient sleep syndrome, and nocturnal seizures also were muscle contraction. Muscle involvement may be local or general- found. In addition, five of nine patients with obstructive sleep ized. Myoclonic seizures may be related to specific epileptic syn- apnea achieved increased seizure control by the use of continuous dromes or may result from degenerative central nervous system positive airway pressure (CPAP) therapy and antiepileptic drugs. diseases, such as encephalitis, renal failure and postanoxic states.
Other studies have confirmed that the frequency of seizures decrease in patients with sleep-related breathing disorders once Tonic, Clonic and Tonic-clonic Seizures
the sleep disorders are successfully treated.9 Tonic seizures involve flexion or stiffening of muscles. Clonic seizures involve rhythmic flexor spasms usually affecting the en- tire body. Spasms are brief and violent. Incontinence and apnea Drugs used to treat epilepsy commonly disrupt sleep (see may occur. Tonic-clonic seizures combine the characteristics Table 1), and a comorbid sleep disorder may worsen sleep frag- of clonic and tonic seizures. Initially a tonic seizure will occur, mentation. Some antiepileptic drugs are commonly used to treat typically involving extended legs and semiflexed arms. The tonic certain sleep disorders, such as in restless legs syndrome, REM phase lasts about 10 to 20 seconds and transforms into a clonic sleep behavior disorder and periodic limb movements of sleep. seizure with its rhythmic jerking. The entire seizure lasts from Sedation is one of the most common side effects of older one to three minutes. A period of confusion or deep sleep may antiepileptic drugs, with reports of sedation as high as 70 percent follow a tonic-clonic seizure. These seizures are common dur- with Phenobarbital, 42 percent with carbamazepine and val- ing sleep in certain epileptic syndromes and occur only during proate, and 33 percent with phenytoin and primidone. Among newer antiepileptic drugs, sedation rates of 5 percent to 15 percent have been reported for gabapentin, lamotrigine, leveti- Niedermeyer E, Da Silva FL. Electroencephalography: racetam, vigabatrin and zonisamide, and 15 percent to 27 percent basic principles, clinical applications, and related fields. for topiramate in placebo-controlled studies. No significant Philadelphia: Lippincott Williams & Wilkins; 2005. p reports of sedation occurred with tiagabine in placebo-controlled studies, but 25 percent reported sedation in open-label, long-term studies. Felbamate studies revealed reports of sedation and Kotagal P, Yardi N. The relationship between sleep and epilepsy. Semin Pediatr Neurol. 2008 Jun;15(2):42-9.
Baldy-Molinier M, Touchon J, Besset A. Sleep architecture and epileptic seizures. In: Degen R, Neidermeyer E, editors. Recognizing sleep disorders in people with epilepsy is a vital Epilepsy, sleep and sleep deprivation. Amsterdam: Elsevier; step in guiding treatment, and physicians and technologists must be aware of the sleep effects of antiepileptic medications, as well Misulis K, Head T. Netter’s concise neurology. Philadelphia: as the sleep effects from seizures. In patients with comorbid sleep disorders and epilepsy, treatment of the seizure disorder alone may not significantly improve the patient’s overall health. Basil C, Malow B. Sleep and epilepsy. In: Guilleminault C, The person’s sleep may be further worsened, precipitating other editor. Clinical neurophysiology of sleep disorders. Vol. 6. health issues. Raising awareness of sleep disorders affecting peo- Handbook of clinical neurophysiology series. Philadelphia: ple with epilepsy helps ensure the best possible treatments, helps decrease disability from seizures and increases quality of life.
Devinsky O, Ehrenberg B, Barthlen GM, Abramson HS, Luciano D. Neurology. 1994 Nov;44(11):2060-4.
Carney P, Berry R, Geyer J. Clinical sleep disorders, sleep 10. Schweitzer P. Drugs that disturb sleep and wakefulness. In: and epilepsy. Philadelphia: Lippincott Williams & Wilkins; Kryger M, Roth T, Dement WC, editors. Principles and practice of sleep medicine. 4th ed. Philadelphia: Elsevier Saunders; 2005. p. 511. Bear M, Connors B, Paradiso M. Neuroscience, exploring the brain. 3rd ed. Baltimore: Lippincott Williams & Wilkins; 2007. p 593.
Rocamora R, Sánchez-Alvarez JC, Salas-Puig J. The relationship between sleep and epilepsy. Neurologist. 2008 Nov;14(6 Suppl 1):S35-43. EVENTS THAT IMPACT QUALITY OF SLEEP (FDA DRUG SHEETS) Insomnia, sleep disturbances, nightmares, vivid dreams Somnolence, fatigue, insomnia, sleep disturbances, nightmares TABLE 1. ANTIEPILEPTIC DRUGS. COMMONLY OBSERVED, ADVERSE EVENTS IMPACTING SLEEP ASSOCIATED WITH USE.

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