Evidence indicates that dipeptidyl-peptidase 4 (DPP4) plays a distinct role in bone metabolism. However, there has been no report on the association, if any, between circulating DPP4 levels and osteoporosis-related phenotypes. This study aimed to determine if DPP4 predicts osteoporotic fracture (OF) risk in postmenopausal women. This casecontrol study was conducted in multiple centers in Korea. We enrolled 178 cases with OF and 178 age- and body mass index-matched controls. OF was assessed by an interviewer-assisted questionnaire and lateral thoracolumbar radiographs. Bone turnover markers (BTMs), bone mineral density (BMD), and plasma DPP4 levels were obtained in all subjects. After adjustment for potential confounders, subjects with OF had significantly higher plasma DPP4 levels than those without (P=0.021). Higher DPP4 levels were significantly associated with higher levels of all BTMs, but not with BMD at all measured sites. The differences in DPP4 levels according to OF status disappeared after an additional adjustment for each BTM, but not after adjustment for any BMD values. The risk of OF was 3.80-fold (95% CI=1.539.42) higher in subjects in the highest DPP4 quartile than in those in the lowest quartile after adjustment for potential confounders, including femoral neck BMD. Finally, mediation analyses demonstrated that bone turnover explained about half of the relation between DPP4 and OF. In conclusion, DPP4 may be associated with OF by partially mediating the bone turnover rate. The circulating DPP4 levels may be a potential biomarker that could increase the predictive power of current fracture risk assessment models.
14 - 17 May 2016
European Calcified Tissue Society