Epilepsy in Indigenous and non-Indigenous people in Far North Queensland

OBJECTIVE: To compare patterns of epilepsy in Indigenous and non-Indigenous people presenting to hospital. STUDY DESIGN: Retrospective cross-sectional survey of individuals admitted to hospital with a diagnosis of epilepsy (1 January 2001 - 31 December 2004); presenting to the emergency department with a seizure (2004); or presenting to the epilepsy clinic (1 September 2002-31 March 2005). SETTING: Cairns Base Hospital, the major referral centre for Far North Queensland, including Cape York and the Torres Strait, with a population of 230 000 (13% Indigenous). MAIN OUTCOME MEASURES: Proportion of Indigenous patients presenting for epilepsy; proportion of Indigenous and non-Indigenous groups affected by each of the main epilepsy syndromes. RESULTS: Of 359 patients attending the epilepsy clinic and 918 patients having electroencephalography (EEG), 11% and 13% were Indigenous, respectively (in proportion with the catchment population). However, 30% (146/486) of patients presenting to the emergency department with seizure, 31% (130/418) of inpatient admissions with epilepsy, and 44% (28/63) of patients admitted with status epilepticus were Indigenous. Indigenous patients were more likely to have an abnormal EEG result (P = 0.025), while non-Indigenous patients presenting to the clinic were more likely to be classified as non-epileptic (31% v 18%). In those with abnormal EEG, the frequency distribution of abnormalities was similar, and, in those with epilepsy, syndrome classification also showed similar frequencies. There was no significant difference in occurrence of epileptogenic abnormalities detected by imaging (13% non-Indigenous v 18% Indigenous) or in alcohol consumption (38% v 37%). CONCLUSIONS: Indigenous Australians have similar epilepsy syndromes to the non-Indigenous population, but they present with more serious disease. This discrepancy may relate to inequitable health care utilisation due to cultural issues or geographic isolation.