Effects of laparoscopic Roux-en-Y gastric bypass on bone mineral density and markers of bone turnover

Abstract Background Despite multiple beneficial effects of weight loss after laparoscopic Roux-en-Y gastric bypass (LRYGB), the influence on bone mineral density (BMD) remains largely unknown. Our objective was to evaluate the changes in BMD and serum/urine bone markers after LRYGB. Methods Thirty-four women undergoing LRYGB were prospectively enrolled and underwent bone densitometry and serum/urine analysis preoperatively and 1 year postoperative. Changes≥.025 g/cm 2 in hip, femoral neck, and spine BMD and decreases>2% in total BMD were considered significant. Statistical analysis included paired t tests and McNemar's test. Results Mean age was 44.6 years. Body mass index at the preoperative and 1-year postoperative intervals were 46.7 and 29.6 kg/m 2 , respectively. Mean hip, femoral neck, and spine (L1–L4) BMD was 1.191 versus 1.087 g/cm 2 ( P 2 ( P 2 ( P 2 at 1 year postoperative ( P P = .004). Elevated osteocalcin and bone alkaline phosphatase was observed in 4% and 63% ( P P = .011) of patients preoperatively and at 1 year postoperative, respectively. Conclusion BMD and bone markers changed significantly after LRYGB. Current recommendations for supplementation in post-LRYGB women may need to be reevaluated.