[Bone mineral density of the femoral neck, a cross-sectional study of normal values in 827 French women aged 36 to 86 years].

The need for determining country-specific reference bone mineral density values has been emphasized. The effects of age and time since menopause on femoral neck bone mineral density in healthy women are still insufficiently documented. The goal of this study was to determine age-specific femoral neck bone mineral density values and postmenopausal bone loss rates in French women. Dual-energy X-ray absorptiometry was used to measure lumbar spine, femoral neck, and Ward's triangle bone mineral densities in 827 women aged 36 to 86 years. Inclusion criteria included a negative history for established or suspected osteoporosis. A cross-sectional, retrospective design was used. Lumbar spine bone mineral densities were similar to reference values reported previously in healthy subjects from other countries. Consequently, we considered that the femoral neck values that we obtained were those of a healthy population. Results were as follows: 1) The annual rate of bone loss at the femur increased within one or two years after menopause (to 1.5% and 2% at the femoral neck and Ward's triangle, respectively), remained high for 12-13 years, then declined (0.8% and 1.2%, respectively). 2) Femoral bone loss was slow before the age of 55 years (0.2% and 0.5% per year) and continued at a faster rate thereafter (1.3% and 1.7% per year). Our study provides normal reference femoral bone mineral density values for French women. Our data confirm that age and time since the menopause have a substantial influence on bone mineral density, not only at the lumbar spine, but also at the femoral neck.