Analysis of bone mineral density and clinical related factors in female patients with type 2 diabetes mellitus

Objective: To investigate the changes of bone mineral density(BMD) in female patients with type 2 diabetes mellitus(T2DM) and the possible clinical related factors involved.Methods: The BMD was measured with the dual-energy X-ray absorptiometry technique at the lumbar(L₂-L₄) and proximal femur of 127 female patients with T2DM and 78 non-diabetic controls.The patients and controls were divided into groups according to the age and diabetic duration.The correlation of BMD with the age,duration of menopause,body mass index(BMI),course,HbA1c and serum lipids was studied by multivariate stepwise regression analysis.Results: The T2DM patients in 55-59 years-old group had a higher BMD than the controls(P<0.05 or P<0.01);the patients in 60-69 and 70-79 year-old groups had a higher BMD at L₂ than the controls(P<0.05 or P<0.01);and the patients in 70-79 year-old group had a higher BMD at L₃ than the controls(P<0.05 or P<0.01).The BMD at Ward's triangle was lower than that at lumbar,neck and G.T in each group(P<0.01).The BMD had no significant difference in T2DM patients with a diabetic course of less than 5 years,between 6-10 years and more than 10 years(P>0.05).Stepwise regression analysis showed that BMD at lumbar was negatively correlated with the age(P<0.05 or P<0.01);BMD at neck,Ward's triangle and G.T.was negatively correlated with the duration of menopause(P<0.01),and positively correlated with BMI(P<0.01).Diabetic duration,HbA1c and serum lipids had no correlation with BMD in T2DM patients.Conclusions: BMD in postmenopausal T2DM patients is significantly higher than or similar to that in the controls.Aging and long duration of menopause are risk factors for decreased BMD in T2DM patients.BMI may be a protective factor for bone loss.