Epidemiology of Treated Epilepsy in New Zealand Children: A Focus on Ethnicity.

Abstract

To determine the period prevalence and incidence of treated epilepsy in a New Zealand pediatric cohort with a focus on ethnicity and socioeconomic status. This was a retrospective cohort study. The New Zealand Pharmaceutical Collection database was searched for individuals ≤18 years of age dispensed an antiseizure medication (ASM) in 2015 from areas capturing 48% of the New Zealand pediatric population. Medical records of identified cases were reviewed to ascertain the indication for the ASM prescription. Population data were derived from the New Zealand 2013 Census. A total of 3,557 ASMs were prescribed during 2015 in 2,594 children, of whom 1,717 (66%) children had epilepsy. An indication for prescription was ascertained for 3,332/3,557 (94%) ASMs. The period prevalence of treated epilepsy was 3.4 per 1,000 children. Children in the most deprived areas had 1.9 times the rate of treated epilepsy (95% confidence interval [CI] 1.6-2.2) as those from the least deprived areas. Prevalence was similar for most ethnic groups (European/other: 3.7, 95% CI 3.4-3.9; Pacific Peoples: 3.6, 95% CI 3.2-4.1; Māori: 3.4, 95% CI 3.1-3.8) apart from Asians, who had a lower prevalence of 2.3 per 1,000 (95% CI 2.0-2.6). However, when adjusted for socioeconomic deprivation, the prevalence of epilepsy was highest in European and similar in Māori, Pacific, and Asian children. This is the largest pediatric epidemiology epilepsy study where diagnosis of epilepsy was confirmed by case review. This is the first study to provide epidemiologic information for pediatric epilepsy in Māori and Pacific children.