Evaluation of bone metabolism and bone mass in patients with type-2 diabetes mellitus

The objectives of this study were to determine whether type-2 diabetes was associated with a higher bone mineral density (BMD) in men and women and to evaluate the differences in mineral metabolism between diabetic and normal subjects by using biochemical bone turnover markers. In this study, 52 patients (37 females/15 males) aged 41-64 with type-2 diabetes mellitus and 48 nondiabetic control subjects (34 females/14 males) were evaluated. In men, BMD was significantly higher in diabetics at the forearm (p <0.05), whereas in women tended to be higher at the hip (p=0.002). Serum osteocalcin (p<0.0001), bone alkaline phosphatase (BAP) (p<0.05) and carboxyterminal telopeptide (CTx) (p<0.05) were higher in the control group than in diabetics. In men, serum osteocalcin (p<0.05) and CTx (p<0.005) and, in women, serum osteocalcin (p<0.0001) and BAP (p<0.05) were lower in diabetic subjects. In conclusion, our findings suggest that although bone formation is decreased in type-2 diabetes, diabetic patients are not susceptible to bone resorption. This low bone turnover can slow the rate of bone loss and cause a higher bone density than expected for their age.