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Estimates of the prevalence, incidence and severity of dementia in Ireland

  • T. Pierse (a1), E. O’ Shea (a1) and P. Carney (a1)

In this paper we provide revised estimates of the prevalence of dementia in Ireland, the number of new cases per year and the severity mix. These estimates are a necessary input for any assessment of the potential demand for services and supports for people with dementia across all care settings in Ireland.


The prevalence, incidence and severity stage of dementia are calculated by applying rates from prominent international studies to population data from the 2016 census.


We show that the total number of people with dementia in Ireland ranges between 39 272 and 55 266, depending on the international rates used to measure prevalence. The incidence of dementia in Ireland has increased as the population has aged, to at least 7752 new cases per year. We estimate that there are at least 11 175 people living at home in the community in Ireland with dementia who have a serious functional impairment, based on an Activities of Daily Living measurement, of which an estimated 1876 are chair or bedbound.


Without a national prevalence study it is not possible to be precise about the estimates of the number of people with dementia in Ireland. However, having credible upper and lower bound estimates for the number of people with dementia, the potential number of new cases per year and severity rates is useful for planners and those charged with the responsibility of making resource allocation decisions in dementia.

Corresponding author
*Address for correspondence: T. Pierse, Postdoctoral Researcher, Centre for Economic and Social Research on Dementia, ILAS Building, NUI Galway, Galway, Ireland. (Email:
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Irish Journal of Psychological Medicine
  • ISSN: 0790-9667
  • EISSN: 2051-6967
  • URL: /core/journals/irish-journal-of-psychological-medicine
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