Vasomotor symptoms are not associated with reduced bone mass in postmenopausal women: the Rancho Bernardo Study

The association of menopause-related vasomotor symptoms with later bone mineral density (BMD) at axial and appendicular sites was examined in community-dwelling older women. Subjects were 894 postmenopausal women from the Rancho Bernardo Study who had BMD measured in 1988-1991 and responded to a 1989 mailed survey that included questions about menopause symptoms. Mean age was 73 years (SE +/- 9.5, range 47-97), and mean age at menopause was 47 years (SD +/- 6.8, range 21-62). Vasomotor symptoms were recalled by two thirds (68%) and night sweats by 36% of all women, with no significant differences in symptom frequency by age or type of menopause. Postmenopausal estrogen (PME) had been used by 644 women (72%) for an average duration of 12.3 (+/-11) years. Among women who reported current estrogen use with a duration >3 years, those who experienced vasomotor symptoms had significantly higher BMD at the lumbar spine (p = 0.01), femoral neck (p = 0.05) and midshaft radius (p = 0.05) compared with women who did not experience symptoms. Vasomotor symptoms were not associated with BMD among past or never PME users or among women who reported current PME use for 3 or fewer years. Analyses stratified by age, type of menopause, or when PME use began showed similar results. Women who reported night sweats also had no difference in BMD compared with women without night sweats. In conclusion, vasomotor symptoms are not a marker for low BMD years after menopause in women with access to healthcare. Vasomotor symptoms significantly increased the likelihood of continued use of PME, which was in turn associated with higher BMD levels.