title: [Projections about the future number of dementia sufferers: increasing life expectancy not sufficiently considered?].
abstract: BACKGROUND
  Several authors pointed out that in the next decades dementia will affect a considerably increasing number of the elderly. The question was raised if life-expectancy was projected to conservative, resulting in revisions with higher life-expectancy and larger numbers of the oldest population. The present paper analyses the influence of such revisions on the future numbers of dementia sufferers in Austria.
  
  
  METHODS
  For this purpose we used meta-analyses of epidemiological studies and the population projections for the period until 2050 of the Austrian Bureau of Statistics as well as of the United Nations Population Division of the year 2001 as well of the year 2005.
  
  
  RESULTS
  Using the extrapolations of the Austrian Bureau of Statistics of the year 1999 as well as of the United Nations Population Division of the year 2001, the number of dementia cases in Austria in the year 2050 will rise to about 233 thousands. According to the four years later performed extrapolations of the United Nations Population Division of the year 2005, dementia cases in Austria will raise to about 262 thousands in the year 2050.
  
  
  CONCLUSIONS
  In the next decades, the number of persons suffering from dementia will rise considerably. Increasing life-expectancy will result in markedly higher numbers of persons with dementia than estimated from earlier population projections. Nevertheless, this is the first analysis of future dementia cases based on projections from two different dates, but using the same source. We must conclude that the dramatically increasing number of dementia cases requires comprehensive planning of the health and social care system.
authors.affiliation: Clinical Division of Social Psychiatry, Department of Psychiatry and Psychotherapy, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria, johannes.wancata@meduniwien.ac.at.
authors.forename: Johannes
authors.initials: J
authors.lastname: Wancata
authors.forename: Marion
authors.initials: M
authors.lastname: Freidl
authors.forename: Annemarie
authors.initials: A
authors.lastname: Unger
authors.forename: Rebecca
authors.initials: R
authors.lastname: Jahn
authors.forename: Nathalie
authors.initials: N
authors.lastname: Soulier
authors.forename: Matthäus
authors.initials: M
authors.lastname: Fellinger
authors.forename: Regine
authors.initials: R
authors.lastname: Daniel
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001317:Austria / Q000453:epidemiology; D003704:Dementia / Q000453:epidemiology*; D006801:Humans; D008017:Life Expectancy / Q000639:trends*; D011157:Population Dynamics; D015995:Prevalence