Type 1 diabetes patients have lower strength in femoral bone determined by quantitative computed tomography: A cross‐sectional study

Aims/Introduction Previous studies have reported osteoporosis measured by dual‐energy X‐ray absorptiometry in younger patients with type 1 diabetes. Limitations of 2‐D imaging, however, limit the precision of dual‐energy X‐ray absorptiometry for the measurement of bone mineral density and bone strength. Materials and Methods Three‐dimensional quantitative computed tomography was used to calculate volumetric‐bone mineral density ( vBMD ) and strength in femoral bone subfractions. A total of 17 male type 1 diabetes patients and 18 sex‐matched healthy controls aged from 18 to 49 years were investigated in the present cross‐sectional study. Patients with overt nephropathy were excluded. Results Type 1 diabetes patients had significantly lower cortical vBMD in the femoral neck, and significantly lower total vBMD , cortical thickness and cortical cross‐sectional area (cortical CSA ) in the intertrochanter. Bone strength estimated by the buckling ratio (an index of cortical instability) of the intertrochanter was significantly higher in type 1 diabetes patients. The following serum bone markers were comparable between the two groups: bone‐specific alkaline phosphatase, N‐terminal propeptide of type 1 procollagen, osteocalcin, pentosidine and homocysteine. Serum insulin‐like growth factor‐1 values were significantly lower in the type 1 diabetes patients than in controls. Serum insulin‐like growth factor‐1values were positively correlated with serum bone formation markers, and the total vBMD of the femoral neck and lumbar spine in type 1 diabetes patients. Conclusions The present study is the first investigation by quantitative computed tomography measurement to show cortical instability and lower vBMD in the intertrochanter of young and middle‐aged type 1 diabetes patients. Low insulin‐like growth factor‐1 might be a causative factor for osteoporosis in type 1 diabetes.