Abstracts

Epidemiological estimates of epilepsy in Canada are sparse. No national data have been published. We assessed the point-prevalence of self-described epilepsy in the general population, nationally, provincially, and in different demographic segments. We analyzed data from two national health surveys, the National Population Health Survey (NPHS, 49,000 respondents) and the Community Health Survey (CHS 130,882 respondents). Both surveys captured socio-demographic information, as well as age, sex, education, ethnicity, household income and labor force status of participants. Epilepsy was ascertained with one question in both surveys. (Do you have epilepsy diagnosed by a health professional? in the NPHS) and (Do you have epilepsy? in the CHS). Weights for probability sampling were applied in the CHS. Prevalences were age-adjusted using national standard population data at the time of each survey. In the NPHS, 241 subjects described themselves as having been diagnosed with epilepsy, yielding an adjusted point prevalence of 4.9 per 1,000 (95% CI 4, 6). In the CHS, 835 described themselves as having epilepsy, yielding a weighted point prevalence of 5.6 per 1,000 (95% CI 4, 6). Epilepsy prevalence was statistically significantly higher in groups with the lowest educational level, lowest income, and in those unemployed in the previous year. Prevalence was also higher in non-immigrants than in immigrants, and in provinces nearer to the Atlantic Ocean. This is the first study exploring the prevalence of epilepsy in Canada and in different demographic groups. The overall and group-specific results are in keeping with those obtained in other developed countries, and using different ascertainment methods. In addition, heretofore unrecognized geographic variations emerged. We discuss methodological aspects related to the ascertainment of epilepsy in both surveys, and the possible implications of our findings.