Type 2 diabetes is a major public health problem, associated with an increased risk of fractures. Diabetes even appears to be the most important predictor of low kinetic fractures in men and women, and the risk of hip fracture in type 2 diabetics is increased by 40 to 50%, with often more serious consequences (post-operative complications, longer hospital stays, increased mortality rate).

Currently, the risk of fractures is estimated by the measure of areal bone mineral density (aBMD) and T-score. However, in diabetics aBMD is not decreased, and even paradoxically increased. Indeed, aBMD is 5-10% higher in type 2 diabetic patients compared to non-diabetic subjects, which suggests that the assessment of fracture risk in these patients is underestimated. The High Resolution peripheral Quantitative Computed Tomography (HR-pQCT) 3D bone imaging technique has a resolution close to the size of the bone trabeculae. It is used to assess volumetric bone mineral density (vBMD) and bone microarchitecture at the tibia and distal radius, and enables a better estimation of the fracture risk compared to the measurement of aBMD. Our hypothesis is that bone microarchitecture is altered in type 2 diabetic patients, explaining the increased risk of fracture in this population compared to non-diabetics.

We propose to set up a descriptive case control study, nestled in 3 cohorts of men and women (QUALYOR, OFELY and STRAMBO), to compare the bone micro-architecture measured by HR-pQCT at the level of the tibia and distal radius, in type 2 diabetics compared to non-diabetic subjects from the same cohorts.

Inclusion Criteria:

• Men and women included in the 3 cohorts (QUALYOR, OFELY, STRAMBO) presenting type 2 diabetes
• Age- and sex-matched control patients from the same cohorts without type 2 diabetes ; two control were age- and sex-matched to one type 2 diabetes patient.

Exclusion Criteria:

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Men and women included in the 3 cohorts (QUALYOR, OFELY, STRAMBO)