Discordant pattern of peripheral fractures in diabetes: a meta-analysis on the risk of wrist and ankle fractures.

To clarify if the peripheral microarchitectural abnormalities described in diabetics have clinical consequences, we evaluated the risk of wrist and ankle fractures. The meta-analysis resulted in an increase in the risk of ankle fractures and a decrease in wrist fractures risk, suggesting that microarchitecture may not be the major fracture determinant.

INTRODUCTION: There is evidence for an increase in the risk of hip fractures in diabetes (both in type 1 and 2), but the risk is not established for other skeletal sites. Microarchitecture evaluations have reported a decrease in volumetric bone mineral density and an increase in cortical porosity at the radius and tibia. To investigate if there is a clinical consequence for these microarchitectural abnormalities, we performed a systematic review and meta-analysis on the risk of ankle and wrist fractures in diabetes.

METHODS: Medline and Embase were searched using the terms 'diabetes mellitus', 'fracture', 'ankle', 'radius' and 'wrist'. Relative risks and 95% confidence intervals were calculated using random effects model.

RESULTS: For ankle fractures, six studies were selected including 2,137,223 participants and 15,395 fractures. For wrist fractures, 10 studies were eligible with 2,773,222 subjects and 39,738 fractures. The studies included men and women, ages 20 to 109 years for the wrist and 27 to 109 years for the ankle. The vast majority of subjects had type 2 diabetes. Diabetes was associated with an increase in the risk of ankle fractures (RR 1.30 95%CI 1.15-1.48) and a decrease in wrist fractures (RR 0.85 95%CI 0.77-0.95). In the studies that reported body mass index (BMI), the mean values were 10% higher in the diabetic groups than controls.

CONCLUSION: The risk of fractures is increased in diabetes at the ankle and decreased at the wrist. The same pattern is observed in obesity. Although bone microarchitectural features are different in obesity and diabetes, the epidemiology of peripheral fractures is similar in both diseases suggesting that microarchitecture may not be the major determinant of peripheral fractures in these populations.