Improving clinical decisions for women at risk of osteoporosis: dual-femur bone mineral density testing.

CONTEXT: In bone mineral density (BMD) testing, unilateral hip analysis and lumbar spine measurement have been the clinical standard for diagnosis and treatment classification for postmenopausal women at risk of osteoporosis.

OBJECTIVE

To determine if analysis of the bilateral hip in BMD testing has a clinical effect on diagnosis of osteoporosis and treatment classification of patients.

METHODS

Dual-femur BMD test results from 313 postmenopausal women (mean age 61.2 years, range 32-90 years) were evaluated using standard BMD reference values for diagnosis and treatment classification. The author compared T scores for right and left femurs at three sites: femoral neck, trochanter, and total femur.

RESULTS

When the bilateral hip was considered in BMD testing and compared with unilateral hip results, a clinical change in diagnosis from normal to osteopenia occurred in 5.7% of subjects. In addition, a clinical change in diagnosis from osteopenia to osteoporosis occurred in 3.3% of subjects. A clinical change in treatment classification from "no treatment required" to "treatment required if one or more risk factors are present" occurred in 3% of subjects. A change in treatment classification from "treatment required if one or more risk factors are present" to "treatment required independent of risk factors" happened in 2.4% of subjects.

CONCLUSION

When compared with BMD testing of the unilateral hip, inclusion of the bilateral hip in BMD testing resulted in a change in classification to a more severe diagnosis in a total of 9% of subjects, and to a more aggressive treatment category in a total of 5.4% of subjects. Dual-femur BMD testing may improve diagnosis and treatment classification for postmenopausal women at risk of osteoporosis.