The implications of body fat mass and fat distribution for cognitive function in elderly women.
OBJECTIVE
To investigate how body fat mass, an established source of endogenous estrogen after menopause, influences cognitive impairment in elderly women.


METHODS
Study participants were 5607 generally healthy postmenopausal women with mean age of 63.8 years at baseline followed for an average of 7.3 years. Cognitive function assessed at follow-up using the short Blessed test was related to baseline body weight, the yearly change in weight, and follow-up measures of body fat depots assessed by DXA. Cognitive function was also related to various surrogates of lifetime estrogen exposure.


RESULTS
Women with the worst cognitive performance (score >or= 9) at follow-up were the ones who lost the most body weight and revealed the lowest central fat mass (CFM). The association of weight loss with worse cognitive performance was apparent across all age groups except for those more than 80 years old. In the multivariate logistic model, the risk of cognitive impairment was 18% lower in women in the second quartile of CFM (p = 0.14), 32% lower in the third (p = 0.01), and 48% lower in the fourth (p < 0.001) compared with those in the first quartile. CFM showed significant correlation with the simultaneously measured serum estradiol (r = 0.25; p < 0.001). Cognitive score showed an inverse linear relationship with the duration of reproductive period and bone mineral density assessed at follow-up.


CONCLUSIONS
These findings argue for a protective association of body fat mass with cognitive impairment in elderly women. This association seems to involve a more prominent exposure to endogenous estrogens.
Center for Clinical and Basic Research A/S, Ballerup Byvej 222, DK-2750 Ballerup, Denmark. yb@ccbr.dk.
Yu Z
YZ
Bagger
László B
LB
Tankó
Peter
P
Alexandersen
Gerong
G
Qin
Claus
C
Christiansen
D000273:Adipose Tissue; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001823:Body Composition / Q000502:physiology*; D015519:Bone Density; D003071:Cognition / Q000502:physiology*; D004958:Estradiol / Q000097:blood; D015914:Estrogen Replacement Therapy; D005260:Female; D006801:Humans; D016015:Logistic Models; D008875:Middle Aged; D012098:Reproduction; D013997:Time Factors; D015431:Weight Loss / Q000502:physiology
D004958:Estradiol