A prevalence study of epilepsy in Hong Kong

Objectives. To examine epidemiological data on epilepsy for the Hong Kong west region. Design. Descriptive study. Setting. Epilepsy clinic, university teaching hospital, Hong Kong. Patients and methods. The epilepsy clinic of Queen Mary Hospital manages the majority of adult patients (aged 15 years or older) with chronic seizure disorders resident in the Hong Kong west area with an adult population of 475 900. All patients underwent electroencephalography examination and each subject was independently assessed by two epileptologists for diagnosis and classified according to the International League Against Epilepsy recommendations. Results. Seven hundred and thirty-six patients (female, 42.9%; male, 57.1%; mean age, 40.8 years; standard deviation, 13.6 years) with epilepsy were enrolled in the study. The prevalence rate of active epilepsy in the population 15 years or older was estimated at 1.54 per 1000 on 1 January 2002. Two hundred and eightyfive (38.7%) patients had idiopathic epilepsy syndromes, 100 (13.6%) had cryptogenic epilepsy, and 285 (38.7%) had a remote symptomatic aetiology. Seizure type was partial in 408 (55.4%) patients and generalised in 285 (38.7%). Thirty-one (4.2%) patients had a positive family history. Idiopathic generalised epilepsy syndromes described as common in the literature, such as juvenile myoclonic epilepsy and childhood absence epilepsy, were infrequently seen at 0.68% and 0.95% of cases, respectively. Conclusions. This study provides baseline data for epilepsy service development and research in Hong Kong. The prevalence rate of active epilepsy in this Chinese, adult population was low compared with that reported in other developed countries. Further population-based epidemiological research is indicated to confirm the prevalence of seizure disorders in this locality.