LAUSR

BackgroundThis study evaluated early and medium-term changes in bone turnover markers, and their associations with weight loss, total bone mineral density (BMD), and hormonal changes after biliopancreatic diversion (BPD).MethodsAncillary study from a one-year prospective cohort of 16 individuals assessed before, 3 days, 3 and 12 months after BPD. Bone turnover markers (C-terminal telopeptide (CTX), intact osteocalcin (OC), sclerostin, and osteoprotegerin (OPG)) and several hormones were measured at each visit. Total BMD by DXA was assessed at baseline, 3 and 12 months after BPD. Three participants were lost to follow-up.ResultsCTX increased significantly at 3 days (+ 66%), 3 months (+ 219%), and 12 months (+ 295%). OC decreased at 3 days (− 19%) then increased at 3 months (+ 69%) and 12 months (+ 164%). Change in sclerostin was only significant between 3 days and 3 months (+ 13%), while change in OPG was significant between baseline and 3 days (+ 48%) and baseline and 12 months (+ 45%). CTX increase correlated negatively with weight loss at 3 (r = − 0.63, p = 0.009) and 12 months (r = − 0.58, p = 0.039), and total BMD decrease (r = − 0.67, p = 0.033) at 12 months. Change in insulin and adiponectin correlated with changes in bone turnover markers independently of weight loss.ConclusionBPD causes an earlier and greater increase in bone resorption over bone formation markers and a decrease in total BMD. Sclerostin did not increase as expected following extensive weight loss. Changes in insulin and adiponectin seem to play a role in the activation of bone remodeling after BPD.