Background
The relationship between obesity and osteoporosis has been widely studied. Studies
have shown that relative fat mass (RFM) can be used to predict obesity. However, its
relationship with bone mineral density (BMD) is unclear. The aim of this study was to
investigate the relationship between RFM and lumbar BMD.
Methods
We used data from the National Health and Nutrition Examination Survey (NHANES)
from 2011 to 2018. Multiple linear regression models were applied to examine the
relationship between RFM and lumbar BMD. We used smoothed curve fitting and
threshold effect analysis to check for non-linear trends. Subgroup analyses were
performed to explore differences in various populations. The Receiver operating characteristic
(ROC) curve was used to evaluate the diagnostic potential of body mass
index (BMI), weight-adjusted waist circumference index (WWI), waist circumference
(WC), and RFM for OP.
Results
A total of 10636 participants were included. Multiple linear regression showed a
significant negative link between RFM and lumbar BMD. In subgroup studies and
smoothed curve fitting, RFM was consistently associated with lower BMD across
subgroups. ROC curve indicate that RFM is more sensitive than BMI, WWI and WC
in diagnosing OP capacity.
Conclusion
RFM is negatively associated with lumbar BMD in US adults. This suggests that RFM
contributes to the study of low BMD.