The Relationship Of Body Composition And Bone Mineral Density(BMD) In Different Body Mass Index(BMI) Level In Middle-aged And Eldly Patients With Type 2 Diabetes

Objective:To explore the relationship between body composition and bone mineral density(BMD)of lumbar spine and femoral neck in middle-aged and elderly patients with type 2 diabetes mellitus(T2DM)in different body mass index(BMI)levels.Methods:Two hundreds and seventy patients with type 2 diabetic patients(122 males and 148 females)hospitalized in the First Hospital of Qinhuangdao from September 2019 to October 2021 were retrospective conducted in this cross-sectional study,including 122 males(age:67.16±8.54)and 148 females(age:66.34±8.51).The basic information of age,sex,history of diabetes,smoking and drinking history,height,weight,waist circumference(WC),systolic blood pressure(SBP),diastolic blood pressure(DBP)were recorded,and BMI was calculated.Fasting venous laboratory indexes including glycosylated hemoglobin(Hb A1c),fasting blood glucose(FBG),uric acid(UA),triglyceride(TG),total cholesterol(TC),high density lipoprotein(HDL-C)and low density lipoprotein(LDL-C)were collected.Lumbar spine and femoral neck BMD and body composition were measured by dual-energy X-ray absorptiometry and total lean mass(TMM),lean mass index(LBMI),skeletal muscle mass index(SMI),total body fat mass(TFM)and total body fat mass index(FMI)were recorded.The BMD of lumbar spine and femoral neck,as well as body composition were measured by dual-energy X-ray(DXA).According to BMI,they were divided into three groups(A,B,C):A group(18.5-23.9kg/m~2n=93),B group(24.0-27.9 kg/m~2n=133)and C group(28.0 kg/m2-35kg/m~2n=44).The differences of age,drinking history,waist circumference,TFM,TMM,bone mineral density and other variables between different BMI groups was used single factor ANOVA test to compare through SPSS statistical software and bone mineral density,TMM and fat indexes were performed on spearman correlation analysis and multivariate linear regression analysis.Results:(1)There were not significantlly differences in age,gender,diabetes history,smoking and drinking history,DBP,Hb A1c,FBG,TG,HDL-C,LDL-C and lumbar BMD among the three groups(P>0.05).There were significantlly differences in WC,BMI,SBP,UA,TG,TMM,LBMI,SMI,TFM,FMI and femoral neck BMD among the three groups(P<0.05).The WC,BMI,UA,LBMI,SMI,FMI and TFM(kg)in C group were significantly higher than those in group B and A group.The WC,BMI,UA,TG,TMM,LBMI,SMI,TFM,FMI and BMD of left and right femoral neck in C group and B group were significantly higher than those in A group.The SBP in B group was higher than that in A group.(2)In the spearman analysis,there were significantly correlated(P<0.05)with lumbar spine BMD and age(r=-0.160,P=0.005),TFM(r=0.254,P=0.000),TMM(r=0.194,P=0.001),LBMI(r=0.378,P=0.000)and SMI(r=0.357,P=0.000),whole there were significantly correlated(P<0.05)with and age(r=-0.369,P=0.000),TFM(r=0.244,P=0.000)and TMM(r=0.162,P=0.004)in the total population;There were significantly(P<0.05)correlated with lumbar spine BMD and TMM(r=0.432,P=0.000),LBMI(r=0.260,P=0.012),whole there were significantly(P<0.05)correlated with femoral neck BMD and age(r=-0.570,P=0.000)and LBMI(r=0.235,P=0.024)in normal weight population;There were significantly(P<0.05)correlated with lumbar spine BMD and FMI(r=-0.175,P=0.046),TMM(r=0.480,P=0.000),LBMI(r=0.363,P=0.000)and SMI(r=0.339,P=0.000),whole there were was significantly correlated(P<0.05)with femoral neck BMD and age(r=-0.238,P=0.007),TMM(r=0.396,P=0.000),LBMI(r=0.298,P=0.001)and SMI(r=0.270,P=0.002)in overweight people;,There were significantly correlated(P<0.05)with lumbar spine BMD and FMI(r=-0.360,P=0.016),TMM(r=0.575,P=0.000),LBMI(r=0.455,P=0.002)and SMI(r=0.486,P=0.001).whole there were significantly correlated(P<0.05)with femoral neck BMD and TMM(r=0.448,P=0.002),LBMI(r=0.335,P=0.026)and SMI(r=0.351,P=0.019)in the obesity population.(3)Lumbar spine BMD and femoral neck BMD was as dependent variables and age,gender,drinking history,diabetes history,TMM,SMI,TFM and FMI was as independent variables.With the increase of BMI,TMM was independently correlated with lumbar spine BMD in A group(R~2=0.178,P=0.000),B group(R~2=0.236,P=0.000)and C group(R~2=0.330,P=0.000),while SMI,TFM and FMI were not independently correlated with lumbar BMD(P>0.05).With the increase of BMI,TMM was independently associated with femoral neck BMD in B group(R~2=0.162,P=0.008)and C group(R~2=0.201,P=0.002).SMI,TFM and FMI were not independently associated with femoral neck BMD(P>0.05)showed in multiple linear regression analysis.Conclusions:1.lumbar spine BMD and femoral neck BMD increased with the increase of body mass index in middle-aged and elderly patients with type 2 diabetes.2.In the overweight and obesity group,lumbar spine BMD and femoral neck BMD were positively correlated with total body TMM mass(TMM),while lumbar spine BMD and fat mass index were only negatively correlated in the overweight and obesity group,and there was not significantlly correlation between femoral neck BMD and fat mass index.3.With the increase of BMI,the relationship between lumbar spine BMD and total body muscle mass(TMM)is getting closer and closer,while femoral neck BMD is closely related to total body muscle mass in overweight and obesity people,so total body muscle mass rather than total fat mass is an independent factor to maintain lumbar BMD and femoral neck BMD.