The Application Of Bone Microstructure Changes And Exercise Balance Function In Postmenopausal Women With Osteoporotic Fractures In Risk Assessment Of Osteoporosis And Fractures

Part 1 The relationship between peripheral trabecular bone microarchitecture and fragility fracture in postmenopausal women who are deemed non-osteoporotic by DXABackground Although areal bone mineral density(aBMD)is a strong and independent predictor for fracture,more than a half of fragility fractures occur among individuals with normal aBMD or osteopenia by dual energy X-ray absorptiometry(DXA).In these patients,aBMD values are normal or only mildly decreased,and the fracture risk assessment(FRAX)tool sometimes cannot distinguish between patients at low and high risk.Methods We designed a cross-sectional study comparing high-resolution peripheral quantitative computed tomography(HRpQCT)parameters in osteopenia or normal-BMD postmenopausal women with and without fragility fracture.The participants were from the Chinese Vertebral Osteoporosis Study(ChiVOS).Study procedures included a face-to-face encounter,coordinator-administered study questionnaire,DXA measurement,thoracolumbar X-ray and blood sample collection.Volumetric BMD and microarchitecture were measured at the distal radius and distal tibia with a three-dimensional HRpQCT system.Results We enrolled 147 postmenopausal women with aBMD T-scores>-2.5(mean age 70.1 years;49 with fragility fractures and 98 controls).The two groups had similar age and BMI.The fracture group had significantly higher rate of fall history after 50 years.The fracture group had lower trabecular vBMD at the radius,and lower trabecular number,higher trabecular separation and inhomogeneity of network at the radius and tibia.The differences in trabecular number at the radius,along with trabecular separation and inhomogeneity of network at the radius and tibia were independent of weight,height and total hip aBMD,or FRAX major osteoporotic fracture scores.Further comparison of ROC curves showed that the model including FRAX-BMD,HR-pQCT indices(Tb.N and Tb.Sp at distal radius)and fall history has a better discriminating power than the model including FRAX-BMD alone(area under the curve 0.68(0.60,0.76)v.0.59(0.50,0.67),p=0.055).We also found similar trabecular bone abnormalities in the subgroup of patients with osteopenia in the fracture group.Compared to non-osteoporotic women without fracture,those with vertebral fracture had lower trabecular number,higher trabecular separation and inhomogeneity of network at the radius and tibia after adjusting for FRAX major osteoporotic fracture scores.Conclusion Trabecular microarchitecture is impaired and fall risk is higher among normal-BMD or osteopenia women with fractures.The model including trabecular microarchitecture and history of fall together with FRAX scores performed better in discriminating fracture patients from healthy participants than FRAX alone.Part 2 The relationship between physical performance,osteoporosis and fracture risk assessmentBackground Although the FRAX(?)tool covers femoral neck bone density and multiple clinical risk factors,it does not include fall risk and physical function.In recent years,more and more studies have shown that physical performance is closely related to bone health,but there is currently no large-scale study on the relationship between physical performance tests and fracture in the Chinese elderly population.Methods We designed a cross-sectional study based on the Chinese Osteoporosis Prevalence Study to explore the correlation between physical performance tests and bone mineral density and fractures.Results 17,489 participants over the age of 40 were included in the current study.Gait speed,5 times sit to stand tests,sharpened Romberg test significantly correlated to fractures and bone mineral density(BMD).After adjusting for sex,age,BMI,BMD,and other clinical risk factors,a positive sharpened Romberg test was significantly associated with a decrease in bone density in the lumbar spine and hip(p<0.0001).Five times sit to stand test was significantly associated with vertebral fractures and clinical fractures in recent 5 years,with the odds ratio of vertebral fracture prevalence reaching 1.95(95%CI 1.25,3.04,p=0.011),the odds ratio of clinical fracture prevalence in the past 5 years reaching 1.98(95%CI 1.30,3.02,p=0.0076)in subjects with>10.8s or failure to complete,compared with subjects with completion of<7.2s.Conclusion After adjusting for BMD and multiple clinical risk factors,sharpened Romberg test was significantly associated with BMD,while five times sit to stand test was significantly associated with vertebral fractures and clinical fractures in recent 5 years.Further longitudinal studies are needed to clarify the role of physical performance on fracture risk prediction.