Decreased cortical thickness, as estimated by a newly developed ultrasound device, as a risk for vertebral fracture in type 2 diabetes mellitus patients with eGFR of less than 60 mL/min/1.73 m(2)

SUMMARY: Cortical porosity is increasingly recognized as an important risk for fracture in DM patients. The present study demonstrated that decreased cortical thickness, assessed using a newly developed quantitative ultrasonic bone densitometry, is a significant risk factor for vertebral fractures in type 2 diabetes mellitus patients with stage 3 or higher chronic kidney disease, but not in those without. INTRODUCTION: Cortical porosity is increasingly recognized as an important risk factor for fracture in type 2 diabetes mellitus (T2DM) patients as well as in stage 3 chronic kidney disease (CKD) patients in whom serum parathyroid hormone (PTH) starts to increase. The present study aimed to clarify whether the coexistence of CKD might affect the relationship of decreased cortical thickness (CoTh) in the development of vertebral fractures (VF) in T2DM patients. METHODS: In this cross-sectional study, trabecular bone mineral density (TrBMD), elastic modulus of trabecular bone (EMTb), and CoTh were estimated with a new quantitative ultrasound bone densitometry in 173 T2DM patients. VFs were identified radiographically. RESULTS: Thirty-nine patients (22.5 %) had VF. Those with estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m(2) (low eGFR) showed a significantly higher VF rate (32.4 %) than those with eGFR ≥60 mL/min/1.73 m(2) (high eGFR, 16.2 %). Serum PTH was significantly higher with low eGFR than with high eGFR. In those with high eGFR, EMTb was significantly lower in VF(+) than VF(−). In those with low eGFR, TrBMD, EMTb, and CoTh were significantly lower in VF(+) than in VF(−). In a multivariate logistic regression analysis, EMTb was independently and significantly associated with VF in T2DM patients with a high eGFR, in contrast to those with only CoTh with VF in T2DM with low eGFR. CONCLUSION: This study demonstrated CoTh as a factor independently associated with VF in T2DM patients with low eGFR and increasing serum PTH levels. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00198-014-2843-x) contains supplementary material, which is available to authorized users.