Grip strength may facilitate fracture prediction in perimenopausal women with normal BMD: a 15-year population-based...

The aim of the present study was to investigate the ability of grip strength measurements to predict fracture risk in perimenopausal women according to bone mineral density (BMD). A random sample of 971 perimenopausal women from the Kuopio Osteoporosis Risk Factor and Prevention study cohort was measured with dual-energy X-ray absorptiometry (DXA) at the femoral neck and grip strength with a pneumatic squeeze dynamometer in 5-year intervals from baseline (1989-1991). Fractures during the 15-year follow-up were recorded based on self-reports and validated from medical records. In the total sample and in osteopenic or osteoporotic women (T score < -1, n = 284) grip strength was not significantly associated with fracture-free survival rate (P = nonsignificant in Cox regression). In women with normal baseline BMD (N-BMD, T score > -1, n = 687) the lowest grip strength quartile had a significantly lower fracture-free survival rate in the Cox proportional hazard model (P = 0.005, hazard ratio [HR] = 2.0). In the multivariate Cox regression model, T score and grip strength were the only significant predictors of 15-year fracture-free survival in the N-BMD group and a risk index (RI) was formed according to HRs of these two variables. High RI (0-5 points) was associated with significantly lower 15-year fracture-free survival rate (P = 0.001, HR = 0.137) in the N-BMD group. In contrast, 5-year T score was no better a predictor of fractures in the baseline N-BMD group (P = 0.04, HR = 0.36). In conclusion, grip strength predicts 15-year fracture-free survival in perimenopausal women with N-BMD, while 5-year DXA does not seem to be any better a predictor of fracture risk. DXA measurements could be coupled with simple and cost-effective grip strength measurements. Controlling BMD in women with N-BMD could be abandoned.