Use of spoken and written Japanese did not protect Japanese-American men from cognitive decline in late life.
OBJECTIVE
Spoken bilingualism may be associated with cognitive reserve. Mastering a complicated written language may be associated with additional reserve. We sought to determine if midlife use of spoken and written Japanese was associated with lower rates of late life cognitive decline.


METHODS
Participants were second-generation Japanese-American men from the Hawaiian island of Oahu, born 1900-1919, free of dementia in 1991, and categorized based on midlife self-reported use of spoken and written Japanese (total n included in primary analysis = 2,520). Cognitive functioning was measured with the Cognitive Abilities Screening Instrument scored using item response theory. We used mixed effects models, controlling for age, income, education, smoking status, apolipoprotein E e4 alleles, and number of study visits.


RESULTS
Rates of cognitive decline were not related to use of spoken or written Japanese. This finding was consistent across numerous sensitivity analyses.


CONCLUSIONS
We did not find evidence to support the hypothesis that multilingualism is associated with cognitive reserve.
Crane
Paul K
PK
Department of Medicine, University of Washington, Seattle, WA, USA. pcrane@u.washington.edu
Gruhl
Jonathan C
JC
Erosheva
Elena A
EA
Gibbons
Laura E
LE
McCurry
Susan M
SM
Rhoads
Kristoffer
K
Nguyen
Viet
V
Arani
Keerthi
K
Masaki
Kamal
K
White
Lon
L
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001213:Asian / Q000523:psychology*; D003072:Cognition Disorders / Q000517:prevention & control* / Q000523:psychology; D054242:Emigrants and Immigrants; D006254:Hawaii; D006801:Humans; D007564:Japan / Q000208:ethnology; D007802:Language; D007807:Language Tests; D008297:Male; D019303:Multilingualism; D015999:Multivariate Analysis; D009483:Neuropsychological Tests; D012044:Regression Analysis; D013060:Speech