The AU-ROCs in this study were 0.71 (95% CI, 0.67-0.75) for baseline total hip BMD, 0.61 (95% CI, 0.56-0.65) for change in total hip BMD between baseline and 3-year BMD scan, and 0.73 (95% CI, 0.69-0.77) for the combined baseline total hip BMD and change in total hip BMD. For femoral neck and lumbar spine BMD, AU-ROC values demonstrated comparable discrimination of hip fracture and MOF as those for total hip BMD. The AU-ROC values among age subgroups (< 65 years, 65-74 years, and ≥ 75 years) were also similar. Associations between change in bone density and fracture risk did not change when adjusted for factors such as BMI, race/ethnicity, diabetes, or baseline BMD.
WHAT’S NEW
Results can be applied to a wider range of patients
This study found that for postmenopausal women, a repeat BMD measurement obtained 3 years after the initial assessment did not improve risk discrimination for hip fracture or MOF beyond the baseline BMD value and should not be routinely performed. Additionally, evidence from this study allows this recommendation to apply to younger postmenopausal women and a variety of high-risk subgroups.
CAVEATS
Possible bias due to self-reporting of fractures
This study suggests that for women without a diagnosis of osteoporosis at initial screening, repeat testing is unlikely to affect future risk stratification. Repeat BMD testing should still be considered when the results are likely to influence clinical management.
However, an important consideration is that fractures were self-reported in this study, introducing a possible source of bias. Additionally, although this study supports foregoing repeat screening at a 3-year interval, there is still no agreed-upon determination of when (or if) to repeat BMD screening in women without osteoporosis.
A large subset of the study population was younger than 65 (44%), the age when family physicians typically recommend screening for osteoporosis. However, the age-adjusted AU-ROC values for fracture risk prediction were the same, and this should not invalidate the conclusions for the study population at large.
CHALLENGES TO IMPLEMENTATION
No challenges seen
We see no challenges in implementing this recommendation.
ACKNOWLEDGEMENT
The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center for Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center for Research Resources or the National Institutes of Health.
