To Investigate Between Bone Mineral Density In Different Parts Of The Body And Predicted Value Of FRAX^? With The Correlation Of BMI In Postmenopausal Women

Objective:To investigate the association of bone mineral density（BMD）and the fracture risk calculated by fracture risk assessment tool(FRAX^?)with body mass index（BMI）in postmenopausal women.Methods:313 postmenopausal women who received BMD examination in the First Affiliated Hospital of Bengbu Medical College from September 2020 to August 2021were selected to collect the demographic information（name,contact number,age,sex,height,weight,history of fractures,parents’history of hip fractures,history of smoking,history of excessive alcohol consumption,history of glucocorticoid use,history of rheumatoid arthritis,and history of other secondary osteoporosis）,BMD and BMD-T value of lumbar spine,femoral neck,and whole hip,and other related information.The probability of major osteoporotic fractures（spine,forearm,hip,or shoulder）（PMOF）and hip fracture（PHF）in the next 10 years were calculated by the FRAX^?tool,PMOF≥20%and PHF≥3%were considered as high risk population for fracture.According to BMI standards in China,they were divided into underweight group,normal weight group,overweight group and obese group.Analysis:1.The diagnostic rate of osteoporosis was determined according to BMD-T value of the three sites,and the correlation between BMD and BMD-T value with BMI at different sites,and the differences among different BMI groups.2.The diagnostic rate of fracture in high-risk population according to FRAX^?prediction（PMOF and PHF）,to investigate whether there is a difference in predicted value between FRAX^?（BMI）and FRAX^?（BMD-T value）models,and to explore the association of FRAX^?predicted value with femoral neck BMD-T value and BMI,and the differences among different BMI groups.3.Parametric models were set up to compare the predictive values of FRAX^?for different BMI and T value.4.Set fixed parameters,and compare the predicted values of FRAX^?at different country and area models.Results:1.BMD-T value of whole hip>BMD-T value of femoral neck>BMD-T value of lumbar spine.BMD and BMD-T value of lumbar spine,femoral neck and whole hip increased with the increase of BMI,and the differences were statistically significant（P<0.001）.2.The predicted value of FRAX^?（BMD-T）was greater than that of FRAX^?（BMI）.The predicted value of FRAX^?（BMD-T）decreased with the increase of BMI,and the difference was statistically significant（P<0.05）.When BMI<28kg/m~2,the predicted value of FRAX^?（BMI）decreased with the increase of BMI.When BMI≥28kg/m~2,the risk of fracture increased,the differences were statistically significant（P<0.05）.3.When T>-2.5SD,the FRAX^?（BMD-T value）model failed to screen for high-risk fractures in the low-weight population,and the FRAX^?model significantly underestimated the risk of major osteoporotic fractures in postmenopausal women.4.Comparing the predicted values of FRAX^?in different country and regional models,in the case of the same parameters,the predicted values of FRAX^?（China-mainland）model are lower than those of other countries and regions,especially the risk of major osteoporotic fractures.Conclusion:1.Low body weight is a risk factor for fracture,while overweight and obesity are protective factors for fracture.Underweight postmenopausal women,who generally have low BMD,are at a relatively high risk of fracture as assessed by the FRAX^?tool.2.The FRAX^?tool was highly predictive of hip fracture risk both with and without femoral neck BMD-T value,but underestimated the risk of major osteoporotic fractures.