The estimated cost of dementia in Japan, the most aged society in the world Mitsuhiro Sado , Akira Ninomiya, Ryo Shikimoto, Baku Ikeda, Toshiaki Baba, Kimio Yoshimura, Masaru Mimura Published: November 12, 2018https://doi.org/10.1371/journal.pone.0206508
Abstract Objective Dementia has become a global critical issue. It is estimated that the global cost of dementia was 818 billion USD in 2015. The situation in Japan, which is the most aged country in the world, should be critical. However, the societal cost of dementia in Japan has not yet been estimated. This study was designed to estimate cost of dementia from societal perspective.
Design We estimated the cost from societal perspective with prevalence based approach.
Setting, participants and measures Main data sources for the parameters to estimate the costs are the National Data Base, a nationwide representative individual-level database for healthcare utilization, the Survey of Long-Term Care Benefit Expenditures, a nationwide survey based on individual-level secondary data for formal long-term care utilization, and the results of an informal care time survey for informal care cost. We conducted the analyses with ‘probabilistic modeling’ using the parameters obtained to estimate the costs of dementia. We also projected future costs.
Results The societal costs of dementia in Japan in 2014 were estimated at JPY 14.5 trillion (se 66.0 billion). Of these, the costs for healthcare, long-term care, and informal care are JPY 1.91 trillion (se 4.91 billion), JPY 6.44 trillion (se 63.2 billion), and JPY 6.16 trillion (se 12.5 billion) respectively. The cost per person with dementia appeared to be JPY5.95 million (se 27 thousand). The total costs would reach JPY 24.3 trillion by 2060, which is 1.6 times higher than that in 2014.
Conclusions The societal cost of dementia in Japan appeared to be considerable. Interventions to mitigate this impact should be considered.
Background Dementia has become a global critical issue, the situation of which could be described as almost ‘under pandemic’. The number of people with dementia across the world is estimated 46.8 million in 2015 and will rise to 131.5 million by 2050 across the world [1]. The impairment caused by the disease ‘characterized by multiple cognitive defects’ [2] is extensive in wide range, including general intelligence, learning and memory, language, problem solving, orientation, perception, attention and concentration, judgment, and social abilities [3]. Given such clinical features, the effects of dementia extend to people’s families and wider society. Both a rapid expansion in the number of people living with dementia and its clinical features contributes to increasing the societal burden. It is estimated that the global cost of dementia was 818 billion USD in 2015 and will reach 2 trillion USD in 2030 [1]. The magnitude of the costs caused by the disorder is attracting huge attention especially in the developed countries. The societal costs of dementia in the US have been estimated to be 157 to 215 billion US dollars in US in 2010 [4], 26 billion pounds in UK in 2013 [5], and 177 billion Euro in whole of Europe and regions according to the classification by United Nations in 2008 [6]. These estimates were influential in the development of policies on dementia at the national or regional level [7][8][9].
The situation in Japan is even more critical. The reason is that Japan is the most aged country in the world [10], where already more than 4.6 million people with dementia live [11]. According to calculation by the authors based on published data, the worldwide prevalence of dementia per capita was around 0.6% in 2015, and is projected to be 1.4% in 2050. In other developed countries such as the UK, the prevalence per capita was already 1.5% in 2013 and still remains approximately 3% in 2050. In contrast, in Japan the prevalence was already beyond 3% in 2015 and will reach close to 9% of the population in 2050 [5][12][13]. These figures illustrate the impact of dementia in Japan. In order to address this issue, the government of Japan launched and updated a national dementia plan in 2012 [14] and in 2015 [15]. However, the plan did not consider the societal costs of dementia, which would bring useful information when evaluating the impact of this disease and help address questions concerning resource allocation. Therefore this study was designed to estimate societal cost of dementia in Japan that will provide evidence based information regarding management of dementia and will be helpful for policy maker to allocate resources for this purpose.
