Estradiol and testosterone levels in diabetic type 2 men with low bone density and osteoporosis
Mário Rui Mascarenhas1,2, Ana Paula Barbosa1, Ema Nobre1, Ana Gonçalves1, Vera Simões1,3, José Camolas2,3, Maria Raquel Carvalho2, Joana Ferreira1, João Vieira2, David Santos Pinto3, Manuel Bicho1 & Isabel do Carmo2
Osteoporosis and diabetes mellitus type 2 (DM2) have severe health consequences, with high morbidity and mortality risks.
Aims: To study the differences of the sex steroid hormones levels and the free androgen index (FAI) in DM2 men with low BMD and osteoporosis and their relationships with BMD.
Materials and methods: In 317 men with DM2, the BMD (g/cm2) was evaluated at the lumbar spine (L1-L4), at the hip and at the distal radius, using a radiological densitometer (Hologic Inc.).
According to the T-score obtained in at least one of those skeletal sites, this population was divided in normal and low BMD and osteoporosis groups. Glycemia, HbA1c, total (testosterone) and free (FT) testosterone and 17beta-estradiol (E2), sex hormone binding globulin (SHBG) were measured. The BMI was also calculated.
ANOVA and multiple regression analysis tests were used to differentiate the several parameters.
Results: The mean age was increased in the osteoporosis group (P<0.05) but the mean BMI and the mean height were reduced in this group (P<0.05). However, the mean testosterone and the mean E2 were significantly decreased in the low BMD and in the osteoporosis groups (P<0.05). The BMD at the lumbar spine and at the hip were significantly related with E2 blood levels, but not with testosterone blood levels. The mean glycemia and the mean HbAc1 levels were identical among the studied groups.
Conclusions: These results suggest that the males with DM2 (duration more than 10 years) over 60-year-old may have an increased risk for osteoporosis. The low sex steroid hormone plasma levels appear to be significant risk factors for osteoporosis in DM2 males. The data of this study imply that increased E2 plasma levels may also play an important role for the relative protection of bone loss mechanisms in DM2 males.