Low Grip Strength is a Strong Risk Factor of Osteoporosis in Postmenopausal Women

Objective To investigate the effect of grip strength on bone mineral density (BMD) in postmenopausal women. Low BMD is related to risk of fracture and falling is the strongest factor for fragility fractures. Handgrip strength is a reliable indicator of muscle strength and muscle strength is associated with falling. Methods For the present study 120 women were divided into two groups: those <= 65years and those >65 years. Serum 25 hydroxyvitamin D (25OHD), BMD, and handgrip strength were measured to observe the effect of age on 25OHD, grip strength, and BMD, as well as the effect of 25OHD on grip strength and BMD. The correlation between grip strength and BMD was investigated. Results In the 120 patients, 25OHD was 24.31 +/- 8.29 ng/mL. There were 37 cases with 25OHD <20 ng/mL and 83cases with 25OHD >= 20 ng/mL. The patients with 25OHD <20 ng/mL had significantly lower femoral neck BMD, most of them with a T score -2.5 (P < 0.05). BMD measurement showed 66 patients with femoral neck T <= -2.5, 30 cases with total hip T <=-2.5 and 90 cases with lumbar BMD T <=-2.5. The maximum grip strength in the group is 22.28 +/- 6.17 kg. There were 38 cases with the maximum grip strength <20kg and 82 cases with the maximum grip strength >= 20 kg. Patients > 65 years had lower 25 OHD, lower maximum grip strength, and lower BMD. The osteoporosis risk in postmenopausal women with a maximum grip strength <20 kg and who were >65 years was significantly elevated. Conclusion Handgrip strength and 25OHD decrease with aging in postmenopausal women. The patients with lower 25OHD level had significantly lower BMD of femoral neck. The patients with lower handgrip strength had significantly lower BMD of lumbar spine, femoral neck, and total hip. Grip strength measurement is the simplest muscle strength measurement method. Our study confirmed that low grip strength was correlated with low BMD and was a strong risk factor for osteoporosis in postmenopausal women.