Correlation between muscle strength levels with bone mineral density and bone metabolism indices at different menopausal stages

Objective To investigate the correlation between muscle strength level and bone mineral density and bone metabolism indexes in postmenopausal women in Beijing. Methods Postmenopausal women who were investigated by on-site questionnaires and followed by bone mineral density examination in Beijing from September 2017 to May 2018 were recruited as study subjects. They were divided into early menopausal group, middle menopausal group, late menopausal group, and twilight menopausal group according to the years of menopause. Changes in grip strength, 5 times sit-to-stand test (FTSST) with bone mineral density (BMD) and bone metabolism indexes were observed in the four groups and their correlations were analyzed. Results A total of 815 cases of postmenopausal women were included. At different menopausal stages, muscle strength was all found to decrease with the increase of menopausal years (P＜0.05), there was non-significance of different bone metabolism indexes among the four groups(P＞0.05); Femoral neck and lumbar spine BMD decreased with the increase of menopausal years(P＜0.05). Maximum grip strength was positively correlated with both femoral neck and lumbar spine BMD (R=0.158, P＜0.05; R=0.130, P＜0.05). There was no correlation between muscle strength and bone metabolism indexes (P＜0.05). Conclusions Different bone metabolism indexes are not associated with muscle strength in menopausal women. Maximum grip strength is positively correlated with bone mineral density, which can be used as an auxiliary screening tool for osteoporosis (OP) in women. The FTSST suggests that the lower limb muscle strength of menopausal women decreases with age, which can be used as one of the indicators for predicting the risk of falls in menopausal women.