Overall, levels of both bone turnover markers increased over time in the study. However, investigators found that concentrations of the bone formation marker P1NP were 13% lower in patients randomized to metformin alone, and 21% lower in patients randomized to metformin and rosiglitazone; no such association was found between P1NP concentrations and treatment with rosiglitazone alone. By contrast, the type of oral antidiabetic drug treatment had no effect on concentrations of CTx concentrations, the investigators said.
Type of insulin treatment received in the trial did not appear to have an impact on concentrations of either bone turnover marker, they added.
HbA1c had no influence on concentrations of P1NP; but it was inversely correlated with levels of CTx, a finding that the investigators said merits more study.
“Further clinical trials investigating the effects of improved glycemic control on bone remodeling including other biochemical markers of bone turnover are needed to confirm if lowering of glucose levels solely changes bone resorption and not formation,” Dr. Stage and his coauthors wrote.
This study was funded with grants from the Danish Council for Independent Research and the Region of Southern Denmark. Dr. Stage and coauthors reported no conflicts of interest related to the report.
SOURCE: Stage TB et al. Bone. 2018 Apr 12;112:35-41.