Abstract for presentation at The Australian and New Zealand Association of Neurologists Annual Scientific Meeting 2007

High prevalence of treated epilepsy in the elderly has implications for future health prevention and service delivery in Australia

  • Dr Wendyl D'Souza, The Menzies Research Institute, The University of Tasmania, Hobart Tasmania & The Department of Medicine, The University of M, Australia
  • Dr Stephen Quinn, The Menzies Research Institute, University of Tasmania, Australia
  • Jayne Fryer, The Menzies Research Institute, The University of Tasmania, Hobart Tasmania, Australia
  • Dr Bruce Taylor, Department of Medicine, Christchurch School of Medicine, New Zealand
  • Dr David Ficker, University of Cincinnati Academic Health Centre, Department of Neurology, United States
  • A/Prof Terence O'Brien, Department of Medicine, The Royal Melbourne Hospital, University of Melbourne, Australia
  • Prof Neil Pearce, Centre for Public Health Research, Massey University Wellington Campus, Wellington, New Zealand
  • Professor Mark Cook, The Department of Medicine, The University of Melbourne, St Vincent’s Hospital Melbourne, Victoria., Australia

    • Background: Studying the prevalence and demographic distribution of epilepsy in community-based populations may potentially highlight important population-level etiological factors underlying this disorder. In Australia, the national anticonvulsant drug (ACD) prescription database has been shown to be representative of community-treated epilepsy.
    Method: We conducted a survey on all persons residing in the island state of Tasmania supplied at least one ACD prescription between 01.07.01 and 30.06.02, through the national prescription database. We estimated the prevalence of treated epilepsy and its demographic distribution, adjusting for the effect of disease non-response bias, by imputation methods. Imputation assumes a linear trend in prevalence with each subsequent contact, allowing the disease prevalence in non-responders to be extrapolated by linear regression.
    Findings: After two mail invitations, 44.8% (3375/7541) responded with 1507 (44.7%) indicating treatment for epilepsy. The adjusted treated epilepsy prevalence was 5.99 per 1000 (5.36-6.62). Without correction for non-response bias, the crude figure, of 8.00 per 1000 (7.70-8.29), would have overestimated prevalence by 33%. Adjusted treated epilepsy prevalence was: lower in women, prevalence ratio (PR) 0.76 (0.62-0.94); higher in northern compared to southern and northwestern regions PR 1.41 (1.13-1.76), and increased monotonically with age (p< 0.001). There was no trend with socioeconomic status of postcode of residence (p=0.5).
    Conclusion: Our estimated prevalence of treated epilepsy in Tasmania is consistent with other studies conducted in communities with high access to health services ascertained either by survey, general practitioner or anticonvulsant prescription sources. The observed pattern of high elderly epilepsy prevalence, is similar to recent studies in other developed countries, and has important implications for future planning of health prevention and treatment services in Australia.

    Conference Organiser - ICMS Pty Ltd