Follicle-stimulating hormone (FSH) levels may independently predict ongoing or imminent bone loss during the menopausal transition, according to study results published in the Journal of Bone and Mineral Research.
By the time the final menstrual period is determined, many women may have already experienced significant bone loss related to menopause. As such, there is a need to prospectively identify potential bone loss in perimenopausal women. To determine whether estradiol or FSH can be used to predict significant bone loss by the next year in women who are premenopausal or perimenopausal, researchers gathered data from 1559 participants (average age, 46.1 years) from the Study of Women’s Health Across the Nation (SWAN). Each woman was measured for estradiol and FSH levels at each follow-up visit (n=3618), as well as for bone mineral density (BMD) at the lumbar spine and femoral neck using dual-energy x-ray absorptiometry.
Using repeated-measures modified Poisson regression and adjusting for menopause transition stage, age, race/ethnicity, study site, and body mass index, the researchers determined that women with lower estradiol and higher FSH levels were more likely to lose BMD at both the lumbar spine and femoral neck.
Each 50% reduction of estradiol was associated with 10% and 12% greater risk for significant bone loss at the lumbar spine (P <.0001) and femoral neck (P =.01), respectively. For each doubling of FSH value, risk for significant bone loss was 39% and 27% greater at the lumbar spine and femoral neck, respectively (P <.0001 for both).
At the individual level, greater declines in estradiol and greater increases in FSH levels predicted risk for imminent bone loss at the lumbar spine, but not at the femoral neck. Overall, tracking within-individual changes in estradiol and FSH levels was not superior to single measures for predicting BMD changes.
Limitations to this study included potential measurement error because of the inability to collect serum samples at the same time point in the menstrual cycle for all participants.
“Future studies will test FSH in combination with clinical covariates and other biomarkers…to develop models that can prospectively identify women who are about to begin losing bone,” said the researchers. “This, in turn, will enable us to test whether early, time-limited interventions can prevent [menopause-transition]-related bone loss, and ultimately whether this reduces the risk of future fracture.”
Shieh A, Greendale GA, Cauley JA, Karvonen-Gutierrez C, Crandall CJ, Karlamangala AS. Estradiol and follicle stimulating hormone as predictors of onset of menopause transition-related bone loss in pre- and perimenopausal women [published online August 23, 2019]. J Bone Miner Res. doi:10.1002/jbmr.3856