Menopausal women who experience moderate to severe hot flashes are 1.78 times as likely to fracture a hip as women of similar age who don’t have hot flashes. Interestingly, the researchers, reporting in The Journal of Clinical Endocrinology & Metabolism, found no association between hot flashes and vertebral fractures. However, they did find that the more severe the hot flashes, the lower the women’s bone density at the femoral neck and lumbar spine.
None of the women studied were using hormone therapy to treat menopause at baseline, and very few started hormone therapy during the mean follow-up of 8.2 years. The findings include statistical adjustment for baseline age, BMI, smoking, and other variables.
Carolyn Crandall, MD, the lead author of the study, told the Washington Post that the reason for the hot flash-hip fracture connection is “entirely a mystery.” But the authors wrote that “our analysis does suggest that impaired physical functioning may partially explain the [hip-fracture] association.” They also surmised that lower estradiol levels in women with hot flashes may partly explain the association between hot flashes and decreased bone density.