Seizures in Children and Adolescents Aged 6–17 Years — United States, 2010–2014

Wanjun Cui, PhD1; Rosemarie Kobau, MPH1; Matthew M. Zack, MD1; Sandra Helmers, MD1; Marshalyn Yeargin-Allsopp, MD2

A seizure is a brief change in normal electrical brain activity resulting in alterations in awareness, perception, behavior, or movement. Seizures affect persons of all ages, but are particularly common in childhood. There are many causes of seizures in children, including epilepsy; high fever (febrile seizures); head injuries; infections (e.g., malaria, meningitis, and gastrointestinal illness); metabolic, neurodevelopmental, and cardiovascular conditions; and complications associated with birth (1–3). Outcomes associated with single or recurring seizures in children vary by seizure type (febrile compared with nonfebrile) and multiple risk factors (age, illness, family history, and family context). Outcomes range from no complications to increased risk for behavioral problems, epilepsy, or sudden unexpected death (3–6). No nationally representative estimates have been reported for the number of U.S. children and adolescents with seizures, co-occurring conditions, or health service utilization. To address these information gaps, CDC analyzed combined data on children and adolescents aged 6–17 years from the National Health Interview Survey (NHIS) for the period 2010–2014. Overall, 0.7% of children and adolescents (weighted national estimate = 336,000) were reported to have had at least one seizure during the preceding year. Compared with children and adolescents without seizures, a higher percentage of those with seizures were socially and economically disadvantaged. Children and adolescents with seizures had higher prevalences of various mental, developmental, physical, and functional co-occurring conditions than those without seizures; however, only 65.6% of those with seizures had visited a medical specialist (defined as a medical doctor who specializes in a particular medical disease or problem, other than an obstetrician/gynecologist, psychiatrist, or ophthalmologist) during the preceding 12 months. Public health agencies can work with other health and human service agencies to raise awareness about childhood seizures, implement strategies to prevent known causes and risk factors for seizures, study the associations between sociodemographic characteristics and seizure incidence, and ensure linkages for children with seizures to appropriate clinical and community providers.

NHIS is an ongoing annual, nationally representative multistage household survey of the U.S. civilian noninstitutionalized population (http://www.cy118119.com/nchs/nhis/about_nhis.htm). CDC analyzed combined 2010–2014 NHIS data from the Sample Child component (questions asked about one randomly selected child from each family in the NHIS), with an average final response rate of 70%. Because these data do not distinguish the relatively large proportion of young children who experience usually benign febrile seizures* from those who have seizures of other etiologies (7), only children and adolescents aged 6–17 years were selected for analysis. Those whose parents provided a "Yes" answer to the survey question, "During the past 12 months, has [your child] had any of the following conditions?" and indicated "seizures" were identified as respondents with seizures.

Multiple outcomes reported by parents of those with and without seizures were examined, including indicators of food insecurity; co-occurring conditions (e.g., neurodevelopmental disabilities, recent infectious illnesses), functional limitations, and taking prescription medications; barriers to care, represented by delaying getting care and being unable to afford care in the past 12 months; access to care or health service utilization in the past 12 months; and the number of missed school days associated with any illness or injury.

Multiple logistic regression was used to calculate the prevalences and 95% confidence intervals (CI) of co-occurring conditions and barriers and access to care, adjusted by sex, race/ethnicity, family poverty income ratio,† and mother's highest level of education, for children with and without seizures. Statistical software was used to account for the NHIS complex survey design and sample child weights. Prevalences were considered statistically significantly different if their CIs did not overlap.

During 2010–2014, parents of 0.7% of children and adolescents aged 6–17 years (weighted national estimate = 336,000) reported that their child had seizures during the past 12 months (Table 1). Children and adolescents with seizures were significantly more likely than those without seizures to live in poverty and low-income families or households (41.6% compared with 28.6%), and were less likely to have mothers or fathers with a bachelor's degree or higher (20.4% compared with 30.6% and 22.4% compared with 34.0%, respectively), or to live in nuclear families or households§ (30.3% compared with 41.9%). Parents of children with seizures also were more likely than parents of children without seizures to report worrying that food would run out (34.5% compared with 22.9%) or that food they bought would not last until they had money to get more (30.9% compared with 19.2%).

Co-occurring conditions were generally more frequently reported by parents of children and adolescents with seizures than by those without seizures (Table 2). Children with seizures had higher reported prevalences of mental or developmental co-occurring conditions, including learning disabilities (43.7% compared with 8.2%); other types of developmental delay (32.3% compared with 4.3%); intellectual disability (22.9% compared with 1.0%); and attention deficit hyperactivity disorder/attention deficit disorder (19.3% compared with 10.3%) than did children without seizures. Parents of children with seizures more frequently reported that their children had headaches or migraines (23.7% compared with 7.0%), hay fever (19.0% compared with 11.2%), and stuttering or stammering (11.3% compared with 1.6%). In addition, children with seizures were more frequently reported to have an impairment or health problem that limited their abilities to crawl, walk, run, or play (23.7% compared with 1.9%); to require special equipment because of impairment or health problems (21.4% compared with 1.1%); and to have taken prescription medication for ≥3 months (68.7% compared with 15.6%) (Table 2).

A significantly higher percentage of parents of children and adolescents with seizures reported delays in getting health care than did parents of children without seizures (14.4% compared with 8.8%) (Table 3). Children and adolescents with seizures were significantly more likely to see different types of health care providers, but 34.4% had not seen a medical specialist during the past 12 months. During the same time period, 41.0% of children and adolescents with seizures visited an emergency department, compared with 15.4% of children and adolescents without seizures. Children and adolescents with seizures reportedly missed six or more school days associated with any illness or injury significantly more frequently than did children and adolescents without seizures (41.9% compared with 14.3%) (Table 3).

Discussion

Seizures in children and adolescents vary by cause, severity, and impact. The risk for some seizures can be prevented or reduced by eliminating their causes, such as ensuring proper prenatal and perinatal care and preventing head injuries. The findings in this report indicate that seizures affect 0.7% of children and adolescents aged 6–17 years, and, relative to the general population, children and adolescents with seizures are socially and economically disadvantaged, more likely to have co-occurring conditions, and more likely to face barriers to care.

The higher observed prevalence of co-occurring conditions is consistent with previous research that has shown a higher prevalence of neurodevelopmental conditions and behavior problems among some children with seizures (3–6). In this analysis, approximately two in five children and adolescents with seizures were reported to have a learning disability and 20%–30% of them had an intellectual disability, attention deficit hyperactivity disorder/attention deficit disorder, or other developmental disorder. Associations between seizures and these conditions might be bidirectional,¶ sharing some common pathophysiological mechanisms (8). Headaches, including migraines, hay fever, and functional disabilities also reportedly affected about one in five children and adolescents with seizures.

Although most children and adolescents with seizures had recently seen a general doctor, they frequently require the care of a specialist, such as a neurologist, and parents of approximately one third of those with seizures reported that they had not recently seen or talked to a medical specialist. Parents reported delays in obtaining care associated with cost and other factors, such as lack of transportation. Higher rates of home care might be associated with severity of co-occurring conditions or transportation barriers. Higher rates of emergency department use might reflect seizure severity, or associated conditions, barriers to routine health care, or other unmet caregiver needs. For example, caregivers might not understand seizure symptoms, or they might be uncomfortable with providing appropriate seizure response.

Overall, parents of children and adolescents with seizures reported higher prevalences of co-occurring conditions; these and the health care utilization patterns and social disadvantages reported by parents of children and adolescents with seizures highlight unmet needs and gaps in care. Children and adolescents with seizures might need coordinated care that ensures accurate diagnosis of seizures and any co-occurring conditions, and that links caregivers with other community organizations to improve health outcomes (9,10).

The findings in this study are subject to at least four limitations. First, the percentage of children and adolescents with seizures was ascertained through parent reports, which were not corroborated by other sources, and might be subject to misclassification or response biases. Second, this study might inadvertently include children and adolescents with febrile seizures. However, because febrile seizures usually occur in children aged 6 months–5 years (7), limiting analyses to children and adolescents aged 6–17 years should have excluded almost all children with febrile seizures. Third, because NHIS data are cross-sectional, causal relationships between seizures and some of the variables cannot be established. Finally, because NHIS does not ask about seizure type and frequency in children and adolescents, it is not possible to confirm whether children and adolescents with reported seizures had epilepsy, or to determine the etiology of the seizure or seizures.

Public health agencies can work with other health and human service agencies to raise awareness about seizures in children and adolescents (e.g., educate parents and school personnel), implement strategies to prevent known causes and risk factors for seizures (e.g., head injuries), study the associations between sociodemographic characteristics and seizure incidence, and ensure linkages to appropriate clinical and community providers for children and adolescents who experience seizures.

1Division of Population Health, National Center for Chronic Disease Prevention and Health Promotion, CDC; 2National Center on Birth Defects and Developmental Disabilities, CDC.

Corresponding author: Wanjun Cui, wtd9@cdc.gov, 770-488-5853.

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