Treatment of vitamin D depletion after Roux-en-Y gastric bypass: a randomized prospective clinical trial

Carlin, Arthur M.; Rao, D. Sudhaker; Yager, Kelli M.; Parikh, Nayana J.; Kapke, Alissa

doi:10.1016/j.soard.2008.08.004

« Previous Next »Surgery for Obesity and Related Diseases
Volume 5, Issue 4 , Pages 444-449, July 2009

Treatment of vitamin D depletion after Roux-en-Y gastric bypass: a randomized prospective clinical trial

Presented, by Arthur M. Carlin, M.D., at the 25th Annual Meeting of the American Society for Metabolic and Bariatric Surgery, June 15-20, 2008, Gaylord National, Washington, DC.

Received 15 May 2008; received in revised form 26 July 2008; accepted 4 August 2008. published online 15 August 2008.

Abstract

Background

A high prevalence (60%) of vitamin D (VitD) depletion, defined as a serum 25-hydroxyvitamin D level of ≤20 ng/mL, is present in preoperative morbidly obese patients. Despite daily supplementation with 800 IU VitD and 1500 mg calcium after Roux-en-Y gastric bypass (RYGB), VitD depletion persists in almost one half (44%) of patients. However, the optimal management of VitD depletion after RYGB and the potential benefits of such treatment are currently unknown.

Methods

A total of 60 VitD-depleted morbidly obese women were randomly assigned to receive 50,000 IU of VitD weekly after RYGB (group 1; n = 30) or no additional VitD after RYGB (group 2; n = 30). All patients received a daily supplement of 800 IU VitD and 1500 mg calcium. The serum calcium, parathyroid hormone, 25-hydroxyvitamin D, bone-specific alkaline phosphatase, urinary N-telopeptide, and bone mineral density were measured preoperatively and 1 year after RYGB. Questionnaires were used to assess other potential sources of VitD, including sunlight exposure and ingestion of VitD-containing foods/liquids.

Results

At 1 year after RYGB, VitD depletion and mean 25-hydroxyvitamin D level had improved significantly in group 1 (14% and 37.8 ng/mL, respectively) compared with the values in group 2 (85% and 15.2 ng/mL, respectively; P <.001 for both). A significant 33% retardation in hip bone mineral density decline (P = .043) and a significantly greater resolution of hypertension was seen in group 1 (75% versus 32%; P = .029). No significant adverse effects were encountered from pharmacologic VitD therapy.

Conclusion

The results of our study have shown that 50,000 IU of VitD weekly after RYGB safely corrects VitD depletion in most women, attenuates cortical bone loss, and improves resolution of hypertension.

Keywords: Morbid obesity, Vitamin D depletion, Parathyroid hormone, Bariatric surgery, Gastric bypass, Hypertension, Bone mineral density, Metabolic bone disease