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Efficacy of Vitamin D Supplementation in Bariatric Surgery Patients

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01385098
Recruitment Status : Completed
First Posted : June 29, 2011
Results First Posted : January 23, 2018
Last Update Posted : January 23, 2018
Texas Woman's University
The Methodist Hospital Research Institute
Information provided by (Responsible Party):
Vadim Sherman, MD, The Methodist Hospital Research Institute

Brief Summary:

As the use of bariatric surgery for treatment of extreme obesity adults continues to rise, clinicians must be aware of pre-existing nutritional deficiencies in overweight and obese patients. Nutritional deficiencies are common in patients undergoing bariatric surgery and these deficiencies should be detected and addressed early to avoid post-operative complications. To improve long-term outcomes following bariatric surgery, nutritional screening and prescribing appropriate supplementation to prevent nutrient deficiencies is needed. Vitamin D deficiency is common following bariatric surgery and has been reported to occur in 50-80% bariatric patients.The goal of this pilot study is to help develop nutrient supplementation interventions following two types of bariatric surgery: Roux-en Y gastric bypass and sleeve gastrectomy.

Recently, several studies in adults have revealed an inverse relationship between body fat and blood 25-hydroxyvitamin D3 [25(OH)D] levels, the relevant marker of low vitamin D status. Although vitamin D is well known for its essential role in bone metabolism and calcium homeostasis, increasing evidence is linking vitamin D to obesity. This study will evaluate vitamin D status during post operative daily supplementation of 2,000 IU of vitamin D3 and 1500 mg of calcium through assessment of changes in serum 25(OH)D, parathyroid hormone (PTH), calcium and phosphorus at baseline, 4 weeks, and 12 weeks following surgery. The dietary contribution of vitamin D and calcium will be estimated by food records analyzed using the University of Minnesota 2010 Nutrition Data System for Research (NDSR) program.

Primary Hypothesis: Daily supplementation with 2,000 IU of vitamin D3 for 12 weeks will significantly increase mean serum 25(OH)D levels in obese subjects following bariatric surgery compared to baseline levels.

Secondary Hypothesis: The percent response above baseline to daily supplementation with 2,000 IU of vitamin D3 will significantly differ between Roux-en Y and sleeve gastrectomy patients.

Condition or disease Intervention/treatment Phase
Obesity Vitamin D Deficiency Dietary Supplement: Vitamin D3 and Calcium Not Applicable

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 37 participants
Allocation: N/A
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Preoperative Vitamin D Status and Efficacy of Therapeutic Vitamin D Supplementation Postoperatively in Bariatric Surgery Patients
Study Start Date : July 2011
Actual Primary Completion Date : May 2013
Actual Study Completion Date : September 2015

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Experimental: Vitamin D3 and Calcium
Dietary supplement of vitamin D3 and calcium
Dietary Supplement: Vitamin D3 and Calcium
1500 mg of calcium citrate plus 1000 IU of vitamin D3 and 1000 IU of vitamin D3 bariatric supplements per day
Other Names:
  • Celebrate ® calcium citrate plus vitamin D3
  • Celbrate ® multi-vitamin

Primary Outcome Measures :
  1. Vitamin D Concentrations, Pre Operative and Post Bariatric Surgery Following 12 Weeks of Vitamin D Supplementation [ Time Frame: baseline and 12 weeks ]
    Serum 25(OH)D ng/ml levels at baseline and 12 weeks following bariatric surgery

Secondary Outcome Measures :
  1. Serum 25-hydroxyvitamin D Levels at Baseline and 12 Weeks of Daily Vit D Supplementation Post Roux-en Y OR Sleeve Gastrectomy [ Time Frame: Baseline and 12 weeks ]
    We anticipate that vitamin D supplementation of Roux-en Y bariatric surgery patients will be less effective in improving or maintaining vitamin D status.

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 65 Years   (Adult, Older Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes

Inclusion Criteria: Adult female obese patients undergoing either Roux-en Y gastric bypass or sleeve gastrectomy at The Methodist Hospital may participate in the study. Obese patients with a body mass index (BMI) > 40 or BMI >35 with a co-morbidity will be eligible.


Exclusion Criteria:Subjects will be excluded if they have evidence of vitamin D deficiency (< 20 ng/mL), hypercalcemia (calcium > 2.63 mmol/L), hypocalcemia (calcium < 1.75 mmol/L), renal insufficiency (GFR < 50 ml/min), or a history of primary hyperparathyroidism or renal tubular acidosis.Participants will be excluded if they take medications that interfere with vitamin D metabolism, have significant sun exposure, plan to travel to sunny climates during the study, or a history of hypercalcemia.


Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01385098

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United States, Texas
The Methodist Hospital
Houston, Texas, United States, 77030
Sponsors and Collaborators
Vadim Sherman, MD
Texas Woman's University
The Methodist Hospital Research Institute
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Study Chair: Susan Miller, MD The Methodist Hospital Research Institute
Principal Investigator: Vadim Sherman, MD The Methodist Hospital Research Institute
Publications of Results:
Other Publications:
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Responsible Party: Vadim Sherman, MD, Sponsor-Investigator/Principal Investigator, The Methodist Hospital Research Institute Identifier: NCT01385098    
Other Study ID Numbers: Pro00005625
0311-0034 ( Other Identifier: HMRI IRB )
First Posted: June 29, 2011    Key Record Dates
Results First Posted: January 23, 2018
Last Update Posted: January 23, 2018
Last Verified: January 2018
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Vadim Sherman, MD, The Methodist Hospital Research Institute:
Vitamin D
Bariatric surgery
Roux-en Y surgery
Gastric sleeve surgery
Parathyroid Hormone
Additional relevant MeSH terms:
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Vitamin D Deficiency
Deficiency Diseases
Nutrition Disorders
Calcium, Dietary
Vitamin D
Physiological Effects of Drugs
Calcium-Regulating Hormones and Agents
Bone Density Conservation Agents