Abstract
Weight loss after gastric bypass procedures has been well studied, but the long-term metabolic sequelae are not known. Data on bone mineral density (BMD), calcium, parathyroid hormone, and vitamin D were collected preoperatively and at yearly intervals after gastric bypass procedures. A total of 230 patients underwent preoperative BMD scans. Fifteen patients were osteopenic preoperatively, and three patients subsequently developed osteopenia postoperatively within the first year. No patient had or developed osteoporosis. At 1 year, total forearm BMD decreased by 0.55% (n = 91; P = .03) and radius BMD had increased overall by 1.85% (n = 23; P = .008); both total hip and lumbar spine BMD decreased by 9.27% (n = 22; P < .001) and 4.53% (n = 31; P < .001), respectively. By the second postoperative year, BMD in the total forearm had decreased an additional 3.62% (n = 14; P<.001), whereas radius BMD remained unchanged. Although total hip and lumbar spine BMD significantly decreased at 1 year, by year 2 both total hip and lumbar spine BMD only slightly decreased and were not significantly different from before the operation. Serum calcium decreased from 9.8 mg/dL to 9.2 during the first year (not significant [NS]) and then to 8.8 (NS) by the second year. Parathyroid hormone increased from 59.7 pg/mL (nl 10-65 pg/mL) preoperatively to 63.1 during year 1 (NS) and continued to increase to 64.7 by year 2 (NS). No difference was noted among levels of 25-hydroxy vitamin D preoperatively (25.2 ng/mL; nl 10-65 ng/mL), at 1 year (34.4), and at 2 years (35.4). Our data indicate that bone loss is highest in the first year after gastric bypass with stabilization, and that, in some cases, there is an increase in bone density after the first year.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Mokdad AH, Serdula MK, Dietz WH, et al. The spread of the obesity epidemic in the United States, 1991–1998. JAMA 1999;282:1519–1522.
Flegal KM, Carroll MD, Ogden CL, et al. Prevalence and trends in obesity among US adults, 1999–2000. JAMA 2002;288:1723–1727.
Andreyeva T, Sturm R, Ringel JS. Moderate and severe obesity have large differences in health care costs. Obes Res 2004;12:1936–1943.
National Institutes of Health Technology Assessment Conference Panel. NIH Conference: methods for voluntary weight loss and control. Ann Intern Med 1992;116:942–949.
Biertho L, Steffen R, Ricklin T, et al. Laparoscopic gastric bypass versus laparoscopic adjustable gastric banding: a comparative study of 1200 cases. J AmColl Surg 2003;197:536–544.
Sugerman HJ, Kellum JM, Engle KM, et al. Gastric bypass for treating severe obesity. Am J Clin Nutr 1992;55:560S-566S.
Zittel TT, Zeeb B, Maier GW, et al. High prevalence of bone disorders after gastrectomy. Am J Surg 1997;174:431–438.
Coates PS, Fernstrom JD, Fernstrom MH, et al. Gastric bypass surgery for morbid obesity leads to and increase in bone turnover and a decrease in bone mass. J Clin Endocrinol Metab 2004;89:1061–1065.
El-Kadre LJ, Rocha PR, de Almeida Tinco AC, et al. Calcium metabolism in pre-and postmenopausal morbidly obese women at baseline and after laparoscopic Roux-en-Y gastric bypass. Obes Surg 2004;14:1062–1066.
von Mach MA, Stoeckli R, Bilz S, et al. Changes in bone mineral content after surgical treatment of morbid obesity. Metabolism 2004;53:918–921.
de Prisco C, Levine SN. Metabolic bone disease after gastric bypass surgery for obesity. Am J Med Sci 2005;329:57–61.
Hamoui N, Kim K, Anthone G, et al. The significance of elevated levels of parathyroid hormone in patient with morbid obesity before and after bariatric surgery. Arch Surg 2003; 138:891–897.
Goldner WS, O’Dorisio TM, Dillon JS, et al. Severe metabolic bone disease as a long-term complication of obesity surgery. Obesity Surgery 2002;12:685–692.
Slater GH, Ren CF, Siegel N, et al. Serum fat-soluble vitamin deficiency and abnormal calcium metabolism after malabsorptive bariatric surgery. J Gastrointest Surg 2004;8:48–55.
Tovey FL, Hall ML, Ell PJ, et al. A review of postgastrectomy bone disease. J Gastroenterol Hepatol 1992;7:639–645.
Crowley LV, Seay J, Mullin G. Late effects of gastric bypass for obesity. Am J Gastroenterol 1984;79:850–860.
DeLuca. Overview of general physiologic features and functions of vitamin D. Am J Clin Nutr 2004;80(suppl):1689S-1696S.
Bell NH, Epstein S, Green A, et al. Evidence for alteration of the vitamin D-endocrine system in obese subjects. J Clin Invest 1985;76:370–373.
Heaney RP. Functional indices of vitamin D status and ramifications of vitamin D deficiency. Am J Clin Nutr 2004; 80(suppl). 1760S-1709S.
Dawson-Hughes B, Heaney RP, Holick MF, et al. Estimated of optimal vitamin D status. Osteoporosis Int 2005; Mar 18; [Epub ahead of print].
Parikh SJ, Edelman M, Uwaifo GI, et al. The relationship between obesity and serum 1,25-dihydroxy vitamin D concentrations in healthy adults. J Clin Endocrinol Metab 2004;89:1196–1199.
Leonard MB, Shults J, Wilson BA, et al. Obesity during childhood and adolescence augments bone mass and bone dimensions. Am J Clin Nutr 2004;80:514–523.
Barrera G, Bunout D, Gattas V, et al. A high body mass index protects against femoral neck osteoporosis in healthy elderly subjects. Nutrition 2004;20:769–771.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Johnson, J.M., Maher, J.W., Samuel, I. et al. Effects of gastric bypass procedures on bone mineral density, calcium, parathyroid hormone, and vitamin d. J Gastrointest Surg 9, 1106–1111 (2005). https://doi.org/10.1016/j.gassur.2005.07.012
Issue Date:
DOI: https://doi.org/10.1016/j.gassur.2005.07.012