The Changes Of Leptin Level, Bone Density And Relevant Factors In Elder Type 2 Diabetes Mellitus

Objective To investigate the change of bone mineral density(BMD) and its relationship with plasma leptin , estradiol(E2) , testosterone(T) and the biochemical markers of bone turnover ( e.g. BGP , B-ALP , TRACP-5b ) in the aging subjects with Type 2 diabetes (T2DM) .Methods 53 patients with T2DM ( ages≥60 years) and 40 control subjects participated in the study. BMD of spine (T12~L3) was measured by QCT, and plasma leptin levels were assayed by RIA. The relationship between BMD and plasma leptin levels , BMI , WHR , E2 , T , bone Gla protein , bone alkaline phosphatase , tartrate resistant acid phosphatase 5b levels was also performed bivariate and multivariate regression analyses.Results The values of spine BMD in T2DM were significantly decreased compared with control〔(74.75±22.70)vs(88.04±28.29)㎎/㎝3,p<0.05〕, and the levels of plasma leptin was also significantly higher than controls〔( 8.97±5.45)μg/L vs ( 6.60±2.67)μg/L , p<0.05〕. Plasma leptin levels were negatively with lumbar 1 BMD and spine mean BMD in the patients with T2DM(r=﹣0.443,r=﹣0.373 ,both p<0.05). Multiple regression analysis showed that plasma leptin levels ,E2 and T were independent related factors influencing BMD in T2DM.Conclusion In elderly patients with T2DM the spine BMD is lower than the controls, but circulating plasma leptin has no the effect on bone mass.