Poster Presentations P3 S463

high TSH (>5mIU/ml) or low vitamin B12 (<180pg/ml) levels were 37 and

11, respectively. Non-depressive patients with significant memory deficits

had a trend of a higher percentage of high TSH levels as compared to those

with normal or slight memory deficits, and this tendency was observed only

in men, but not in women. Eight out of eleven patients with low vitamin B12

levels showed significant memory deficits. Conclusions: We have to con-

sider the possibility of depression for the elderly patients complaining mem-

ory problems at a general practitioner clinic. When restricted to patients

without depression, men with cognitive dysfunction had a tendency of ele-

vated serum TSH levels, indicating the complication of subclinical hypothyr-

oidism.

P3-048 HIGHER CAREGIVER AGREEABLENESS

PREDICTS SLOWER COGNITIVE DECLINE IN

PERSONS WITH ALZHEIMER’S DISEASE: THE

DEMENTIA PROGRESSION STUDY

Maria C. Norton1, Elizabeth Fauth1, Kathy Piercy1, Chris Corcoran1,

Kyle Hess1, Ann Morrison2, Peter V. Rabins2, Constantine G. Lyketsos2,

JoAnn Tschanz1, 1Utah State University, Logan, UT, USA; 2The JohnsHopkins University, Baltimore, MD, USA. Contact e-mail: maria.norton@

usu.edu

Background: Caregiver personality has been linked to mental and physical

health outcomes in the caregiver, however, little is known as to how care-

giver personality may affect the clinical progression of the care recipient.

We recently reported findings of slower cognitive and functional decline in

persons whose caregivers reported closer relationships with their care recip-

ients, in a population-based study of incident Alzheimer’s disease (AD). We

now investigate the association between caregiver personality and cognitive

trajectory in this cohort. Methods: Cognitive status of 111 individuals with

incident AD (41 males, 70 females with age M ¼ 85.7, SD¼ 5.2 years) was

assessed at a maximum of 12 semi-annual visits (median follow-up time 2.4

years) with the Mini-Mental State Exam. Primary caregivers were 43

spouses, and 68 non-spouses. Self-report personality dimensions of Neurot-

icism, Extraversion, Openness, Conscientiousness, and Agreeableness in the

caregiver were assessed with the NEO-FFI. Mixed effects linear models were

conducted separately for each personality domain, with time measured as

a random effect, based on years since dementia onset. Covariates included

subject’s dementia duration, age and education. Results: The only personal-

ity domain significantly related to cognitive trajectory in the care recipient

was caregiver Agreeableness. Moderation by care recipient gender and care-

giver relationship (p ¼ .057, and p ¼ .071 for interaction effects, respec-

tively) was examined in stratified analyses. After covariate adjustments,

a one SD increase in Agreeableness was associated with .78 point per year

less decline on the MMSE among male care recipients (p ¼ 0.0093), but

not for female care recipients (p ¼ .8421). A similar increase in Agreeable-

ness was associated with 0.57 point per year less decline with spouse care-

givers (p ¼ .0089), but not for others (p ¼ .7643). Conclusions:

Caregiver personality is associated with rate of clinical progression in AD.

Agreeableness includes such characteristics as straightforwardness, helpful-

ness, generosity, optimism, and empathy. Such traits may be important for

adaptive caregiving strategies, which are linked to more positive outcomes

for care recipient. Results are preliminary and replication will be needed. Fu-

ture work will examine the relative importance of Closeness vs. Agreeable-

ness, as well as care management strategies used by caregivers high in

Agreeableness.

P3-049 GRIP STRENGTH AS A PREDICTOR OF

MORTALITY AND DEMENTIA: RADIATION

EFFECTS RESEARCH FOUNDATION ADULT

HEALTH STUDY

Michiko Yamada1, Fumiyoshi Kasagi1, Yasuyo Mimori2,

Takafumi Miyachi3, Tomohiko Ohshita3, Hideo Sasaki4, 1Radiation Effects

Research Foundation, Hiroshima, Japan; 2Hiroshima International Uni-versity, Hiroshima, Japan; 3Hiroshima University Graduate School of Bio-

medical Sciences, Hiroshima, Japan; 4Hiroshima Atomic Bomb Casualty

Council Health Promotion Center, Hiroshima, Japan. Contact e-mail:

yamada@rerf.or.jp

Background: Aging is characterized by deterioration of biological function,

resulting in increased morbidity and mortality, but few studies have exam-

ined association between midlife grip strength and risk of mortality or de-

mentia incidence. Methods: We investigated whether midlife grip strength

is associated with risk of death and dementia in the population-based cohort

of the Radiation Effects Research Foundation’s Adult Health Study (AHS).

AHS biennial health examinations have been conducted since 1958. Grip

strength was measured for 1,785 participants born between 1917 and

1932, at clinical examinations during the period from 1970 to 1972. Vital sta-

tus was followed until the end of 2007. By the end of August 1992, 487 sub-

jects had died or dropped out of the follow-up. The remaining 1,298 subjects

were assessed in terms of cognitive function and presence of dementia bien-

nially between 1992 and 2007. Vital status and dementia occurrence at age

75 were assessed by tertile of midlife grip strength. Relative risk of mortality

and dementia incidence associated with midlife grip strength was estimated

after adjustment was made for other potential risk factors by Cox propor-

tional hazard model. Results: A lower percentage of dying subjects and

a higher percentage of dementia-free subjects at age 75 were observed in

the highest tertile of midlife grip strength. Low midlife grip strength was

found to be a risk factor for mortality and dementia incidence after adjust-

ment was made for other potential risk factors. Conclusions: In this prospec-

tive study of middle-aged to elderly Japanese subjects, midlife grip strength

was found to be a predictor of mortality and dementia incidence. The findings

suggest that grip strength is useful not only as a marker of biological function

but also as an indicator of clinical and subclinical pathology or genomic fac-

tors and that physical exercise may contribute to extension of the duration of

dementia-free life.

P3-050 EDUCATION, BASELINE AGE AND APOE4

GENOTYPES ARE ASSOCIATED WITH THE TIME

FOR AN ACCELERATED RATE OF DECLINE IN

VISUOSPATIAL ABILITY PRIOR TO THE

DIAGNOSIS OF ALZHEIMER’S DISEASE

Chengjie Xiong, Yuan Xu, J. Philip Miller, John Morris, Washington Uni-

versity, St. Louis, MO, USA. Contact e-mail: chengjie@wustl.edu

Background: Accelerated cognitive decline occurs years before a clinical di-

agnosis of AD can be rendered. Preclinical AD is a hypothesized stage during

which AD pathology has been accumulating prior to the clinical symptoms.

The concept of cognitive reserve posits that individual differences in how

tasks are processed provide differential reserve against brain pathology or

age-related changes. Methods: We examined the longitudinal patterns of

a visuospatial factor score prior to the diagnosis of AD on a sample of 556

nondemented individuals who went through annual clinical and cognitive as-

sessment for as many as 23 years at Washington University Alzheimer’s Dis-

ease Research Center. Through a joint model of the longitudinal cognitive

scores and the time to the onset of AD, we fitted a changepoint model to as-

sociate the times prior to the onset when the rate of decline in the visuospatial

score was accelerated with education, baseline age, and APOE4 genotypes.

Results: Of 556 nondemented participants at baseline, 139 subsequently de-

veloped AD. Earlier times when the rate of decline was accelerated are sig-

nificantly associated with a higher risk of developing AD (log hazard ratio¼-1.18, p < 0.0001). For individuals at least 75 years of age at baseline, the

mean (and the median) time that the rate of decline was accelerated is shifted

early by 60.59% (p < 0.0001) when compared to those younger than 75 at

baseline. For individuals with at least one APOE e4 alleles, the mean (and

the median) time that the rate of decline was accelerated is shifted early by

17.38% (p < 0.0001) when compared to those with none. For individuals

with at least 12 years of education, the mean (and the median) time that

the rate of decline was accelerated is shifted late by 7.2% (p < 0.0001)

when compared to those otherwise. Conclusions: These results suggest dif-

ferential paths of cognitive decline as a function of two major risk factors

(age and APOE4 genotypes) and a proxy of cognitive reserve (education)

prior to the onset of AD, thereby supporting the cognitive reserve hypothesis

and the hypothesis of preclinical AD.