Longitudinal study of changes in hip bone mineral density in Caucasian and African-American women.
OBJECTIVE
To determine whether changes in hip bone mineral density (BMD) differ in Caucasian and African American women.


METHODS
Longitudinal study of changes in hip BMD.


METHODS
Four U.S. clinical centers.


METHODS
Six thousand seven Caucasian (mean age 73) and 482 African-American (mean age 75) women enrolled in the Study of Osteoporotic Fractures.


METHODS
Total hip and femoral neck BMD were measured an average of 3.5 years apart (Caucasian) and 2.0 years apart (African American). Annual absolute and percentage changes in BMD and bone mineral apparent density (BMAD) were calculated.


RESULTS
The multivariate adjusted annual percentage change in BMD was greater in Caucasian than African-American women at the total hip (-0.574%/y vs -0.334%/y) and femoral neck (-0.515%/y vs -0.203%/y) (both, P<.001). Similar findings were observed for BMAD. The average annualized rate of BMD loss was twice as high in women aged 75 and older as in women younger than 75 in both ethnic groups. The annual percentage loss in femoral neck BMD in nonusers versus hormone therapy users was (-0.57% vs -0.22%) in Caucasians and (-0.35% vs 0.64%) in African Americans (interaction P=.03).


CONCLUSIONS
The average rate of hip BMD loss is approximately twice as great in Caucasian as African-American women and increases with age in both groups. The hormonal and biochemical factors that contribute to ethnic differences and the increase in bone loss with advancing age need to be identified.
Cauley
Jane A
JA
Department of Epidemiology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA. jcauley@pitt.edu <jcauley@pitt.edu>
Lui
Li-Yung
LY
Stone
Katie L
KL
Hillier
Teresa A
TA
Zmuda
Joseph M
JM
Hochberg
Marc
M
Beck
Thomas J
TJ
Ensrud
Kristinee E
KE
D015502:Absorptiometry, Photon; D001741:Black or African American; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D015519:Bone Density; D015914:Estrogen Replacement Therapy; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging / Q000502:physiology*; D006801:Humans; D008137:Longitudinal Studies; D010384:Pelvic Bones / Q000000981:diagnostic imaging / Q000502:physiology*; D012737:Sex Factors; D014481:United States; D044465:White People