SITE OF BONE-DENSITY MEASUREMENT MAY AFFECT THERAPY DECISION

The purpose of this study was to determine whether bone mineral densit y (BMD) measurements at the lumbar spine and femoral neck provided com parable information to women planning to use that knowledge to help th em make a decision about hormone replacement therapy. Eighty-eight hea lthy Caucasian women, aged 44-59 and within 0 to 5 years of menopause, participated in the study. BMD measurements were performed at the lum bar spine (L1-L4) and the femoral neck by dual energy X-ray absorptiom etry (DXA). Criteria suggested by the National Osteoporosis Foundation were used to categorize women as ''at risk'' for osteoporosis, bone d ensity more than one standard deviation (SD) below the young adult mea n, or as ''low risk'', bone density at or above this level. The result s indicated that 46 women would be classified into the low risk catego ry on the basis of spinal BMD alone. However, 28 of these 46 women wou ld fall into the at risk category when the femoral neck BMD was measur ed. Sixty-one percent of women informed they were at low risk on the b asis of spinal BMD would be considered at risk based on femoral neck B MD. When femoral neck BMD was used as the primary risk indicator, 14% of the women classified as low risk would be at risk if spinal BMD wer e added. These results suggest that both lumbar spine and proximal fem ur measurements should be made when women are using bone density measu rements as an aid in deciding whether or not to use hormone therapy in their postmenopausal years.