Is body mass index a measure of adiposity in elderly women?
OBJECTIVE
To evaluate the accuracy of body mass index (BMI) as a predictor of body fat in elderly women.


METHODS
A total of 1423 women aged 67 +/- 5 (mean +/- SD, range: 60 to 88) years were consecutively enrolled into the study. Fat mass (FM) was measured using DXA.


RESULTS
BMI explained 72.9% of FM variance (p < 0.0001), with a root mean square error of estimate (RMSE) of 3.5 kg. After standardization of RMSE on the dependent variable as RMSE%, the prediction error equaled 15%. BMI explained 54.8% of FM% variance (p < 0.0001), with an RMSE of 4.1%, corresponding to an RMSE% of 11%.


CONCLUSIONS
The relatively high RMSE% of the FM and FM%-BMI associations caution against the use of BMI as an adiposity index in individual elderly women. However, an error corresponding to 11% of FM% may be accepted for population studies of body fat in elderly women.
Bedogni
G
G
Department of Biomedical Sciences, University of Modena and Reggio Emilia, Modena, Italy. giorgiobedogni@libero.it
Pietrobelli
A
A
Heymsfield
S B
SB
Borghi
A
A
Manzieri
A M
AM
Morini
P
P
Battistini
N
N
Salvioli
G
G
D015502:Absorptiometry, Photon; D000273:Adipose Tissue; D000368:Aged; D000369:Aged, 80 and over; D001823:Body Composition; D015992:Body Mass Index; D005260:Female; D006801:Humans; D008875:Middle Aged; D009765:Obesity / Q000145:classification* / Q000175:diagnosis*