Serum pentosidine levels are positively associated with the presence of vertebral fractures in postmenopausal women with type 2 diabetes

Context: Although type 2 diabetic patients are at increased risk of fractures, bone mineral density (BMD) may not be useful for assessing the risk. Recent studies have reported that increased bone content of pentosidine (PEN) is associated with its plasma concentration and bone fragility. Objective and Methods: To examine the association between serum PEN levels and vertebral fractures (VFs) in Japanese type 2 diabetic patients (77 males older than 50 yr and 76 postmenopausal females), we compared parameters including BMD, PEN, serum bone-specific alkaline phosphatase, and urinary levels of N-telopeptide between those with and without VFs. Results: Comparison of diabetic subjects with and without VFs revealed no significant differences in BMD values or bone metabolic markers in either gender. In contrast, PEN levels in women with VFs were significantly higher than in those without VFs (0.0440 +/- 0.0136 vs. 0.0321 +/- 0.0118 mu g/ml; P < 0.001). Multivariate logistic regression analysis adjusted for age, height, weight, hemoglobin A1c, estimated glomerular filtration rate, the presence of diabetic complications, histories of taking insulin or pioglitazone, risk factors for osteoporosis, and lumbar BMD identified PEN levels as a factor associated with the presence of VFs in postmenopausal diabetic women independent of BMD, risk factors for osteoporosis, diabetic status, and renal function (odds ratio 2.50, 95% confidential interval 1.09-5.73 per SD increase; P = 0.0302). Conclusion: PEN levels, but not BMD, may be useful for assessing the risk of prevalent VFs in postmenopausal diabetic women and may reflect bone quality in this group.