Elderly Japanese emigrants to Brazil before World War II: II. Prevalence of senile dementia.
BACKGROUND
We previously showed the prevalence of dementia in the town of Tajiri (Miyagi Prefecture, Japan), and found it to be 8.0%. The first population-based study on dementia in Brazil (Catanduva) disclosed the prevalence as being 7.1%. To evaluate the effects of environment on development of dementia, elderly Japanese immigrants living in Brazil were examined. Brazil is the country with the largest number of Japanese immigrants.


METHODS
All immigrants aged 65 years and over from Miyagi Prefecture, living in the four cities of the São Paulo Metropolitan area were targeted (n = 192). We were able to examine 166 subjects (86.5%). The diagnosis of dementia was based on the DSM-IV with the severity assessed by the CDR (clinical dementia rating) scales. The cognitive ability screening instrument (CASI) was used for neuropsychological assessment.


RESULTS
Thirteen subjects were diagnosed with dementia, CDR 1-3, the prevalence being 7.8%. Older subjects suffered more from dementia, and, paradoxically, the more highly educated subjects also suffered more. All the CASI items, except for long-term memory and visual construction, significantly deteriorated in the CDR 0.5 group compared with the CDR 0 group.


CONCLUSIONS
The prevalence of dementia was not thought to be affected by environmental factors. A paradoxically higher rate of dementia in the more educated subjects was probably due to the historical problems of the immigrants. Intact CASI item long-term memory in the CDR 0.5 group indicated that suspected dementia patients could maintain this function. This is the first epidemiological study on dementia in elderly Japanese immigrants in Brazil.
Meguro
K
K
Division of Neuropsychology, Department of Disability Medicine, Tohoku University Graduate School of Medicine, 201 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan. meg@mail.cc.tohoku.ac.jp
Meguro
M
M
Caramelli
P
P
Ishizaki
J
J
Ambo
H
H
Chubaci
R Y
RY
Hamada
G S
GS
Nitrini
R
R
Yamadori
A
A
D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000145:classification / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D001938:Brazil / Q000453:epidemiology; D004522:Educational Status; D004641:Emigration and Immigration / Q000706:statistics & numerical data* / Q000639:trends; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D007564:Japan / Q000208:ethnology; D008297:Male; D008403:Mass Screening; D008609:Mental Status Schedule; D009483:Neuropsychological Tests; D011159:Population Surveillance; D015995:Prevalence; D012307:Risk Factors; D012720:Severity of Illness Index; D017678:Sex Distribution; D014857:Warfare