The use of CPAP in patients with refractory epilepsy

Co-morbid sleep disorders and epilepsy: A narrative review and case examples

Co-morbid sleep disorders, including sleep apnea, insomnia, restless legs syndrome, and the parasomnias, occur frequently in people with epilepsy. This article reviews the cardinal presenting symptoms and diagnostic features of each of these disorders to enable epileptologists to readily screen and identify sleep co-morbidities in their patients. It summarizes current evidence concerning the reciprocal relationship between sleep disturbances and epilepsy and available treatment options for common sleep disorders in people with epilepsy. Several illustrative cases demonstrate the practical consequences of co-morbid sleep disorders in epilepsy patients and suggest diagnostic and treatment approaches that may improve daytime functioning, alertness, quality of life, and seizure burden.

Primary sleep disorders in people with epilepsy: clinical questions and answers

The questions facing clinicians with patients with sleep disorder and epilepsy are addressed in this article. Both adult and child epilepsy are discussed in the context of the most typical questions a clinician would have, such as "Are parasomnias more common in people with epilepsy?", "Is sleep architecture abnormal in children with epilepsy", along with outcomes of numerous questionnaire-based, case-based, and double-blind placebo studies on such aspects as sleep duration, daytime sleepiness, anxiety and fears, limb movement, nocturnal seizures, agitation, behavioral disorders, and learning disorders.

Sleep and comorbid neurologic disorders

PURPOSE OF REVIEW

An understanding of the impact of sleep on neurologic disorders, and the impact of neurologic disorders on sleep, provides fresh opportunities for neurologists to improve the quality of life and functioning of their patients.

RECENT FINDINGS

Sleep-disordered breathing (SDB) is a risk factor for cerebrovascular disease and should be considered in all TIA and stroke patients. Sleep disorders can amplify nociception and worsen headache disorders; and some headaches, including those related to SDB and hypnic headache, are sleep specific. REM sleep behavior disorder may be an early sign of neurodegenerative disease. Focal lesions of almost any etiology (eg, multiple sclerosis and CNS malignancies) in the hypothalamus, basal forebrain, or brainstem may result in sleep disturbance, sleepiness, and insomnia. Sleep-related hypoventilation and fatigue are common in neuromuscular disease. SDB and epilepsy are mutually facilitatory, and poor sleep can exacerbate epilepsy.

SUMMARY

Continued surveillance for sleep disorders by neurologists is rewarded by new treatment avenues in their patients with the possibility of improved clinical outcomes.

Influence of sleep disturbance on quality of life of patients with epilepsy

The frequency of sleep disturbances in patients with epilepsy and their impact on quality of life (QoL) have been documented in a few reports, and the results are conflicting. We identified 124 consecutive epilepsy out-patients who visited the epilepsy out-patient clinics at the University Hospital of Alexandroupolis, the AHEPA Hospital in Thessaloniki and the Aeginitio Hospital in Athens. We measured excessive daytime sleepiness (EDS) with the Epworth Sleepiness Scale (ESS), obstructive sleep apnea (OSA) with the Sleep Apnea scale of the Sleep Disorders Questionnaire (SA-SDQ), and insomnia with the Athens Insomnia Scale (AIS). We evaluated quality of life by the Quality of Life in Epilepsy Inventory (QOLIE-31). EDS was found in 16.9% (21/124) of epileptic patients, OSA in 28.2% (35/124), and insomnia in 24.6% (30/122). In multivariate analysis, we found that insomnia was an independent negative factor for Total score (p<0.001), Overall QoL (p=0.002), Emotional well-being (p<0.001), Energy/fatigue (p<0.001), Cognitive functioning (p=0.04) and Social functioning (p=0.03), and OSA only for Cognitive functioning (p=0.01). According to our findings, EDS, OSA, and insomnia are frequent in epileptic patients. Epileptic patients with sleep disturbance, mainly insomnia, have significant QoL impairment.

Hypoxic adaptation during development: relation to pattern of neurological presentation and cognitive disability

Children with acute hypoxic-ischaemic events (e.g. stroke) and chronic neurological conditions associated with hypoxia frequently present to paediatric neurologists. Failure to adapt to hypoxia may be a common pathophysiological pathway linking a number of other conditions of childhood with cognitive deficit. There is evidence that congenital cardiac disease, asthma and sleep disordered breathing, for example, are associated with cognitive deficit, but little is known about the mechanism and whether there is any structural change. This review describes what is known about how the brain reacts and adapts to hypoxia, focusing on epilepsy and sickle cell disease (SCD). We prospectively recorded overnight oxyhaemoglobin saturation (SpO2) in 18 children with intractable epilepsy, six of whom were currently or recently in minor status (MS). Children with MS were more likely to have an abnormal sleep study defined as either mean baseline SpO2 <94% or >4 dips of >4% in SpO2/hour (p = .04). In our series of prospectively followed patients with SCD who subsequently developed acute neurological symptoms and signs, mean overnight SpO2 was lower in those with cerebrovascular disease on magnetic resonance angiography (Mann-Whitney, p = .01). Acute, intermittent and chronic hypoxia may have detrimental effects on the brain, the clinical manifestations perhaps depending on rapidity of presentation and prior exposure.

Epilepsy and obstructive sleep apnea

A few publications documented the coexistence of epilepsy and obstructive sleep apnea (OSA). The extent, nature, and clinical relevance of this association remain poorly understood. We retrospectively reviewed the database of our sleep center to identify patients with both sleep apnea and epilepsy. Characteristics of epilepsy, sleep history, presence of excessive daytime sleepiness [Epworth Sleepiness Scale (ESS)] and polysomnographic data were assessed. The effect of continuous positive airway pressure (CPAP) on seizure reduction was prospectively analyzed after a median interval of 26 months (range: 2-116 months) from the diagnosis of OSA. OSA was found in 29 epilepsy patients (25 men and 4 women) with a median age of 56 years (range: 37-79). The median apnea hypopnea index was 33 (range: 10-85), the oxygen desaturation index was 12 (range 0-92), and 52% of the patients had an ESS score >10. In 27 patients, epilepsy appeared 1 month to 44 years prior to the diagnosis of OSA. In 21 patients, the appearance of OSA symptoms coincided with a clear increase in seizure frequency or the first appearance of a status epilepticus. Treatment with CPAP was continued with good compliance in 12 patients and led to a significant reduction of both ESS scores and seizure frequency in 4 patients. Our data suggest the importance of considering diagnosis and treatment of OSA in epilepsy patients with poor seizure control and/or reappearance of seizures after a seizure-free interval.

Obstructive sleep apnea in a clinical series of adult epilepsy patients: frequency and features of the comorbidity

PURPOSE

The aim of this study was to evaluate the rate and features of obstructive sleep apnea (OSA) in adult epilepsy patients.

METHODS

Two hundred eighty-three adult epilepsy patients (137 men; mean age, 33 years; range, 18-70 years) were prospectively screened for OSA by means of a structured interview. Those in whom OSA was clinically suspected were monitored for a full night by using a portable device (Polymesam), and OSA was diagnosed when they had an Apnea/Hypopnea Index greater than five.

RESULTS

Coexistence of OSA with epilepsy was found in 10.2% (15.4% of the male and 5.4% of the female) epilepsy patients investigated. The OSA was mild in 66.6%, moderate in 22.2%, and severe in 11.1% of the cases. The "epilepsy + OSA" patients were older, heavier, more frequently male, and sleepier (p < 0.05) than those with "epilepsy only." Furthermore, they experienced their first seizure at an older age (p < 0.05).

CONCLUSIONS

Systematic investigation reveals that OSA is frequent in epilepsy patients. The major risk factors for OSA in our epilepsy patients were the same as those typically found in the general population. Of the epilepsy-related factors, older age at onset of seizures appears to be significantly related to comorbidity with OSA (p < 0.05). The presence in epilepsy patients of these features should alert the clinician to the possibility of an underlying OSA.

Sleep complaints and epilepsy: the role of seizures, antiepileptic drugs and sleep disorders

Patients with epilepsy commonly complain of daytime sleepiness and poor sleep quality. These problems are frequently attributed to antiepileptic drugs and seizures. Antiepileptic drugs and seizures have effects on sleep architecture often leading to daytime sleepiness. However, sleep symptoms may also be caused by poor sleep hygiene and primary sleep disorders. Primary sleep disorders should be suspected in patients with persistent daytime sleepiness, particularly those on AED monotherapy or with low serum drug concentrations and well-controlled seizures. Treatment of sleep disorders and improved sleep hygiene may improve seizure control and quality of life.

Interactions between sleep and epilepsy

Sleep is one of the best-documented factors influencing the expression of seizures and interictal discharges. Janz studied the relation between seizures and the sleep/wake cycle and divided the epilepsies into three categories: nocturnal, awakening, and diffuse. Since then, the effect of sleep on the ictal and interictal manifestations of epilepsy has been studied extensively. Many seizures are activated by sleep or arousal from sleep. Interictal discharges are also seen more commonly during sleep, with the greatest activation seen during nonrapid eye movement sleep. Sleep not only increases the frequency of epileptiform abnormalities, but also may alter their morphology and distribution. Sleep deprivation also facilitates both epileptiform abnormalities and seizures. Seizures, on the other hand, also impact sleep. Epileptic patients demonstrate multiple sleep abnormalities, including an increased sleep latency, fragmented sleep, increased awakenings and stage shifts, and an increase in stages 1 and 2 of nonrapid eye movement sleep. These disturbances may in turn be modulated by antiepileptic treatment. This review summarizes the interactions between sleep and epilepsy, including the timing of seizures during the sleep/wake cycle, the influence of sleep on various seizure disorders, the effects of sleep deprivation, and the changes in sleep patterns caused by seizures and their treatment.