The worldwide societal costs of dementia: Estimates for 2009.

BACKGROUND The purpose of this study was to update the previous estimate of the worldwide cost of dementia in 2005 to 2009. METHODS The cost model is based on prevalence estimates, country and region-specific data on Gross Domestic Product per person and average wage, with results from previously published cost-of-illness studies in different countries. Prevalence figures are updated to 2009 and costs were adjusted to 2009 constant US dollars ($). RESULTS The total worldwide societal cost of dementia, based on a dementia population of 34.4 million demented persons, was estimated to $422 billion in 2009, including $142 billion for informal care (34%). CONCLUSIONS The worldwide cost of dementia has increased by 34% (18% in fixed prices) between 2005 and 2009.