Past research conducted in the field of childhood epilepsy has clearly shown a link between behavioral problems and epilepsy. But, what if these behavioral problems in children with epilepsy could be attributed in part to sleep related difficulties? This is the question Dr. Paul Carney, colleague Dr. Eileen Fennell, and Danielle Becker investigated in a recent study entitled, “Daytime Behavior and Sleep Disturbance in Childhood Epilepsy.” Dr. Paul Carney is the Chief of the Division of Pediatric Neurology and Director of the Pediatric Comprehensive Epilepsy Center at the University of Florida at Gainesville. Dr. Eileen Fennel is a Child Neuropsychologist in the College of Public Health and Health Professions at the University of Florida in Gainesville. Danielle Becker, M.S. was a neuropsychology graduate student when this study was conducted and is now a first year medical student at the University of Miami.

“It’s been known for several decades that there is a clear relationship between sleep and epilepsy. What we wanted to know was the contribution of epilepsy on sleep staging. Our interest was in examining whether daytime behavior problems encountered in children with epilepsy may be directly related to seizure frequency and specific disruptions in sleep,” said Carney.

Did You Know?

Children with epilepsy exhibit more behavioral problems, such as inattention, poor concentration, and opposition, than children with other chronic illnesses or normal children(1). The presence of behavioral problems in children with epilepsy has been linked to abnormal sleep patterns and seizure frequency may contribute to approximately 30% of the variation in behavior problems observed in children with epilepsy.(1,2)

How the Study Was Designed

A total of 30 children with a known seizure disorder were included in the study and were recruited from the outpatient Pediatric Neurology Clinic at the University of Florida. The children were between the ages of 7 and 14. Based on results from the pediatric sleep questionnaire (completed by a parent) as well as verbal endorsement of sleep complaints (during a routine medical outpatient visit) children suspected of having a sleep disorder were referred for an overnight polysomnogram. During the overnight polysomnogram EEG electrodes were placed to monitor seizure activity.

Results

Based on the data collected, none of the children had documented seizures during the overnight polysomnogram. Twenty-four of the thirty children (80%) studied displayed abnormalities on their overnight polysomnograms with evidence of obstructive hypopneas or apneas with associated sleep disruption and mild hypoxemia (lower oxygen levels in the blood than normal). On average, these 24 children spent 4% of their total sleep period time in stage 1 sleep, 45% in stage 2 sleep, 27% in stage 3 and 4 non-REM sleep and 17% in REM sleep. Seizure frequency was found to have a significant effect on the length of apnea indicating that children with a higher frequency of seizures experienced longer apneic events.

The Greek word “apnea” literally means “without breath”. According to the American Sleep Association (ASAA), “there are three types of apnea: obstructive, central, and mixed; of the three, obstructive is the most common. Despite the difference in the root cause of each type, in all three, people with untreated sleep apnea stop breathing repeatedly during their sleep, sometimes hundreds of times during the night.” The ASAA states “Obstructive sleep apnea (OSA) is caused by a blockage of the airway, usually when the soft tissue in the rear of the throat collapses and closes during sleep. In central sleep apnea, the airway is not blocked, but the brain fails to signal the muscles to breathe. Mixed apnea, as its name implies, is a combination of the two. A recent article published by the ASAA states, “OSA is relatively common in the pediatric population, afflicting an estimated 1 to 3 percent of children between the ages of 2 and 18, with boys and girls being equally affected.” (2)

Implications of the Study

Three significant findings arose from this study. First,the results suggest that children with epilepsy also commonly suffer from sleep disorders. Secondly, children with epilepsy as reported by parents have significant problems with inattention/hyperactivity. Lastly, severity of epilepsy does not independently appear to predispose children to having behavioral problems. Instead, behavioral problems are more directly related to the existence of sleep disturbance.

Carney believes that many clinicians do not consider sleep difficulties when treating their pediatric patients with epilepsy. “We feel that many children with epilepsy have an underlying sleep disorder given the results of our study in which 80% of the children with epilepsy also had sleep disorders.” He asserts that “Treating the sleep disorder not only treats the epilepsy, but the behavioral problems as well. As we know sleep deprivation can lead to worsening of epilepsy. So, by treating the sleep disorder there is a positive impact not only on the frequency and severity of seizures but also on the behavioral problems.”

In order to continue progressing towards a greater understanding of the relationship between sleep disturbances and behavioral problems in children with epilepsy he emphasizes the need for a collaborative effort among clinicians of varying specialties.

Treatment Options

The most common treatment used to treat OSA in children is adenotonsillectomy. “Removal of the adenoids and tonsils resolves the problem of OSA in more than three-quarters of children and is the first line of treatment,” according to the ASAA. Another available treatment option is nasal continuous positive airway pressure (CPAP). In this procedure the patient wears a mask over the nose during sleep, and pressure from an air blower forces air through the nasal passages. Nasal CPAP prevents airway closure while in use. It is recommended that the air pressure be evaluated regularly, since pressure requirements change as children grow. Side effects of CPAP may include nasal irritation and drying, facial skin irritation, abdominal bloating, mask leaks, sore eyes, and headaches. Other treatment options include oral uvulopharygoplasty (UPPP), but this procedure has not been well studied in children.

Future Studies

Currently, Carney is embarking on a new study in which he will explore the possibility of shared cognitive and behavioral features between children with epilepsy, sleep apnea, and ADHD.

References

1.Becker DA, Fennell, EB, Carney PR. Sleep disturbance in children with epilepsy. Epilepsy Behav 2003;4(6):651-8.

2.Becker DA, Fennell EB, Carney PR. Daytime behavior and sleep disturbance in childhood epilepsy.Epilepsy Behav 2004;5:708-715.

3.American Sleep Apnea Association, “Wake-Up Call”, Fall 2004.