TY - JOUR
T1 - Discordance between fat mass index and body mass index is associated with reduced bone mineral density in women but not in men
T2 - the Busselton Healthy Ageing Study
AU - Zhu, K.
AU - Hunter, M.
AU - James, A.
AU - Lim, E. M.
AU - Cooke, B. R.
AU - Walsh, J. P.
PY - 2017/1/1
Y1 - 2017/1/1
N2 - Summary: The obesity-BMD relationship is complex. In 3045 middle-aged adults, we found that in women (but not men) with discordant fat mass index (FMI)/BMI categories, higher body fat for BMI was associated with lower BMD, suggesting that increased fat mass without an accompanying increase in lean mass may be deleterious to bone. Introduction: The relationship between obesity and BMD is complex. FMI (fat mass (kg) / height (m)2) is a more accurate measure of fatness than BMI, and depending on body composition, some individuals have discordant BMI/FMI categories. We examined associations between FMI, BMI and BMD in participants in the Busselton Healthy Ageing Study. Methods: Body composition and BMD of the hip, spine and total body were measured using DXA in 3045 participants (1644 females) aged 45–67 years. Using standard BMI/FMI categories, the participants were classified as underweight/fat deficit, normal, overweight/excess fat, obese I and obese II–III. Results: BMI and FMI categories were concordant in 77.3 % of females and 71.2 % of males. There were 12.9 % females and 13.2 % males in a higher FMI than BMI category (high body fat for BMI), whereas 9.8 % females and 15.6 % males were in a lower category (low body fat for BMI). Females with high body fat for BMI had significantly lower covariate-adjusted BMD at the femoral neck, total hip and total body (differences of 3.8, 5.1 and 2.6 %, respectively, all P < 0.05) than females with low body fat for BMI and lower total body BMD than women with concordant FMI/BMI (by 1.4 %, P = 0.04). In males, BMD did not differ significantly between those who were concordant or discordant for FMI/BMI categories. Conclusion: In women (but not men) with discordant FMI/BMI categories, higher body fat for BMI was associated with lower BMD, suggesting that increased fat mass without an accompanying increase in lean mass may be deleterious to bone.
AB - Summary: The obesity-BMD relationship is complex. In 3045 middle-aged adults, we found that in women (but not men) with discordant fat mass index (FMI)/BMI categories, higher body fat for BMI was associated with lower BMD, suggesting that increased fat mass without an accompanying increase in lean mass may be deleterious to bone. Introduction: The relationship between obesity and BMD is complex. FMI (fat mass (kg) / height (m)2) is a more accurate measure of fatness than BMI, and depending on body composition, some individuals have discordant BMI/FMI categories. We examined associations between FMI, BMI and BMD in participants in the Busselton Healthy Ageing Study. Methods: Body composition and BMD of the hip, spine and total body were measured using DXA in 3045 participants (1644 females) aged 45–67 years. Using standard BMI/FMI categories, the participants were classified as underweight/fat deficit, normal, overweight/excess fat, obese I and obese II–III. Results: BMI and FMI categories were concordant in 77.3 % of females and 71.2 % of males. There were 12.9 % females and 13.2 % males in a higher FMI than BMI category (high body fat for BMI), whereas 9.8 % females and 15.6 % males were in a lower category (low body fat for BMI). Females with high body fat for BMI had significantly lower covariate-adjusted BMD at the femoral neck, total hip and total body (differences of 3.8, 5.1 and 2.6 %, respectively, all P < 0.05) than females with low body fat for BMI and lower total body BMD than women with concordant FMI/BMI (by 1.4 %, P = 0.04). In males, BMD did not differ significantly between those who were concordant or discordant for FMI/BMI categories. Conclusion: In women (but not men) with discordant FMI/BMI categories, higher body fat for BMI was associated with lower BMD, suggesting that increased fat mass without an accompanying increase in lean mass may be deleterious to bone.
KW - Baby boomers
KW - Body mass index
KW - Bone mineral density
KW - Busselton Healthy Ageing Study
KW - Fat mass index
KW - Middle-aged adults
UR - http://www.scopus.com/inward/record.url?scp=84980002374&partnerID=8YFLogxK
U2 - 10.1007/s00198-016-3710-8
DO - 10.1007/s00198-016-3710-8
M3 - Article
C2 - 27468902
AN - SCOPUS:84980002374
VL - 28
SP - 259
EP - 268
JO - Osteoporosis International: with other metabolic bone diseases
JF - Osteoporosis International: with other metabolic bone diseases
SN - 0937-941X
IS - 1
ER -