Prevalence of Dementia Among Japanese Americans

Recent studies suggest that the prevalence of dementia in Japan is similar to other countries but that Alzheimer’s disease is rare and vascular dementia is more common. The ratio of vascular disease to Alzheimer’s disease in Japan ranges from 1:1 to 3:1. Studies of Japanese Americans in Hawaii and Kings county suggest that the ratio in this group is similar to the rates reported in Caucasians in the United States and Europe. White et al.2 analyzed data on 3,734 surviving members of the Honolulu Heart Program. They found that elderly Japanese American men have a higher prevalence of Alzheimer’s disease than do similar groups of men living in Japan. Among the Americans of Japanese descent, 9.3% were suffering from dementia of all causes and 5.4% had Alzheimer’s disease (primary or contributing). In comparison, studies from Japan reported that prevalence of dementia in the range of 1.5% of men 65 years or older.2

The Hawaiian study also looked at rates for vascular dementia. Some 4.2% of the Hawaii participants could attribute vascular dementia as a primary or contributing cause of their dementia. A rate of 3.2% was found in one Japanese study.2

The researchers analyze their findings as thus: “Despite substantial problems related to comparability of studies conducted in Japan and the United States, it appears likely that older Japanese American men in Hawaii experience a prevalence of Alzheimer disease approaching that of European-ancestry Americans and a prevalence of vascular dementia only slightly above that observed in Japan. These observations lead us to speculate that environmental or cultural exposures associated with migration from Japan to Hawaii may have influenced the development of Alzheimer disease… while factors involved in the pathogenesis of vascular dementia have remained relatively unaffected.”

Japanese American Cultural Beliefs About Dementia

1. Dementia is a form of normal aging.  Many families interpret the memory difficulties and behavioral problems associated with dementia as the result of normal aging.  One study suggested that due to this belief, some Chinese families do not believe symptoms of dementia represent an illness that requires medical assessment or treatment.(Elliott, Di Minno, Lam et al. 1996

2. Dementia is a form of mental illness. Some Asians families perceive symptoms of dementia( paranoia, hallucinations, delusions etc.) as form of mental illness.   There is a great deal of stigma and shame  associated with dementia and mental illness among Asia American. Japanese words for dementia include kichigai (crazy, insane) and bokeru (senility or forgetful in old age). These negative responses by families and patients interfere with their willing to seek appropriate medical assessment and treatment in the early stages of the illness.

3.Dementia is a family secrets that should not be shared.  The cultural norm for many family is to avoid sharing family secrets or embarrassing information with strangers, including health care providers.  To discuss the problems of caring for a Japanese American elder with dementia with outsiders would cause the family to lose face.

4. Dementia is unavoidable.  Dementia is perceived by some Japanese Americans by the concept of shikata  ganai (“you can’t help it”). This attitude would also delay elders and their caregivers seeking diagnosis or treatment interventions for cognitive disorders.

5. Dementia is an illness you can fight.  Many Japanese Americans are knowledgeable about signs and symptoms of  Alzheimer’s disease. They also engaging in preventative strategies such as regular exercise, remaining mentally active and socializing with others. (Iwamasa et al 1999, 1998, Hillard et al. 1998)

Japanese American Caregiver Attitudes About Dementia

Traditional cultural values such as omae (the importance of interpersonal harmony and relationships), oykoko (filial piety) and giri (obligation to one’s family) encourage caregivers to provide home based  for Japanese elders with dementia. When the elder with dementia lives with his adult children, the primary caregiver is usually the wife of the eldest son or the eldest daughter if there is no son.  There are also many Japanese Americans who live alone or with a spouse who are beginning to use Japanese community based formal social service agencies  such as Keiro Services in Los Angeles.

Recommendations for Health care providers

1. Provide the often overburdened female caregiver information about support services that she and the family are eligible for.

2. Provide accurate assessments of the elder’s ability to conduct activities of daily living since family members may minimize or deny the degree of the elders level of functional impairment.

3. Be knowledgeable about the community and social issues that face the Japanese Americans that you work with.  Develop collaborations with highly regarded, existing Asian community agencies to improve your credibility with patients and their families and increase their likelihood of participating in those services.

4. Develop a therapeutic rapport with your patient’s by utilizing their explanatory models of illness and explain in simple, practical terms how they will benefit from your interventions

5. Provide culturally sensitive, relevant materials about dementia written in the language of the target population

6. Continually expand you knowledge of the culture and social values of Japanese Americans


Elliott K.  Di Minno M, Lam D & Tui A. Working with Chinese Families in the context of dementia. IN G.Yeo and D. Gallagher-Thompson (Eds), Ethnicity and the Dementias. Washington DC: Taylor & Eng. 1996:89-108

White L, Petrovitch H, Ross GW et al. Prevalence of dementia in older Japanese-American men in Hawaii: the Honolulu-Asia aging study. JAMA 1996; 276: 955-60.

Graves AB, Larson EB, Edland SD et. al Prevalence of dementia and its subtypes in the Japanese American population of King County, Washington state. The Kame Project American Journal of Epidemiology, Vol 144, Issue 8 760-771

Gallagher-Thompson D, Hargrave R, Hinton L et al. Interventions in a Multicultural Society. IN D. Coon, D Gallagher-Thompson, LW Thompson (Eds), Innovative Interventions to Reduce Dementia Caregiver Distress. New York City: Springer Publishing 2003:50-73