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CompletedNCT01739855BABSUpdated Aug 25, 2014

Bone Metabolism After Laparoscopic Gastric Bypass Surgery (BABS)

A Phase 2 interventional study of Calciferol, calcium carbonate in Evaluation of Expected Bone Loss After Bariatric Surgery and Possible Prevention of Bone Loss After Surgery by Calcium and Vitamin D Supplementation, sponsored by Medical University of Vienna. Completed at 1 site in Austria. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2014-08-25.

Sponsored by Medical University of Vienna · Phase 2, Interventional, and Treatment

Phase
Phase 2
Study type
Interventional
Enrollment
160
Allocation
Randomized
Ages
18 Years to 65 Years
Sex
All
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Study summary

Bariatric surgery leads to rapid weight loss in female and male patients. Less data are available about its impact on bone metabolism.

The aim of this study is the investigation of changes in bone mineral density,bone histomorphometric changes, serum bone turnover markers and changes in body fat and muscle composition in patients after laparoscopic gastric bypass surgery.

Read the detailed description

Obese female and male adult patients eligible for laparoscopic gastric bypass surgery according to the national Austrian guidelines will be included in this study upon request and after patient approval.

Baseline data collection and quarterly follow up visits are planned to investigate the changes in bone mineral density and body composition measured by dual energy X-ray absorptiometry as well as the evaluation of serum bone turnover markers of bone formation and resorption.

After surgery subjects will be randomized into two groups:

Daily oral calcium (500mg) and weekly vitamin D3 supplementation (16.000 IU calciferol)or no supplementation of calcium and calciferol.

A sub-study (approximately 15% of study population) with transiliac bone biopsies will also be performed to investigate histomorphometric and histologic changes in bone (biopsy baseline and after 24 months).

The planned duration of the study is 24 months for each subject. Serum bone turnover markers will be collected every 3 months, dual energy X-ray absorptiometry measurements will be performed every 6 months.

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Conditions studied

  • Evaluation of Expected Bone Loss After Bariatric Surgery
  • Possible Prevention of Bone Loss After Surgery by Calcium and Vitamin D Supplementation
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In context

Bone Diseases, Metabolic

470 studies on the registry are indexed under Bone Diseases, Metabolic; 71 are open to participants now.

This study's enrollment of 160 is above the median of 60 across 359 interventional studies indexed under Bone Diseases, Metabolic.

Browse Bone Diseases, Metabolic studies →

Lead sponsor

Medical University of Vienna is the lead sponsor of 1,076 studies on the registry; 177 are open to participants now.

Counted across the registry records on this site, refreshed daily.

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Who can participate

Ages eligible
18 Years to 65 Years
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  • body mass index >35
  • female and male patients
  • age 18 - 65 years
  • eligible for laparoscopic gastric bypass surgery according to the Austrian national guidelines

Exclusion criteria

Exclusion Criteria:

  • any history of malignancy except basalioma
  • any prior antiresorptive treatment
  • any prior calcium or vitamin D supplementation
  • any secondary disease affecting bone metabolism
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Study design

Phase
Phase 2
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
160 participants (actual)

Study arms

  • Active comparator
    Calcium/Vitamin D

    All subjects will receive calcium/vitamin D supplementation after laparoscopic bariatric gastric bypass surgery as follows: daily: 500 mg oral calcium (calcium carbonate) weekly: 16.000 IU oral vitamin D3 (calciferol)

    Drug: Calciferol, calcium carbonate

  • No intervention
    No Calcium/Vitamin D

    All subjects will not receive calcium/vitamin D supplementation after laparoscopic bariatric gastric bypass surgery.

Interventions

  • DrugCalciferol, calcium carbonate
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What researchers measure

Primary outcomes

  1. Evaluation of bone mineral density changes in obese patients after laparoscopic bariatric surgery

    Dual energy X-ray absorptiometry (DXA) measurements of bone mineral density at lumbar spine, hip, calcaneus and total body will be performed at baseline and every six months for a period of 24 months. Differences will be evaluated on the outcome with/without daily calcium (500mg) and weekly vitamin D (16.000 IU calciferol) supplementation

    Time frame: Evaluation every 6 months for 24 months

Secondary outcomes

  1. Evaluation of changes of serum bone turnover markers in obese patients after laparoscopic bariatric surgery

    Fasting serum markers of bone formation and bone resorption will be evaluated: Calcium, 25-OH-vitamin D3, intact parathyroid hormone, beta-crosslaps, type-1-procollagen, bone specific alkaline phosphatase, osteocalcin, sclerostin, osteoprotegerin, cathepsin-K, fibroblast factor 23, lipoprotein A, dickkopf 1 Differences will be evaluated on the outcome with/without daily calcium (500mg) and weekly vitamin D (16.000 IU calciferol) supplementation

    Time frame: Evaluation every 3 months for 24 months

Other outcomes

  1. Evaluation of histomorphometric and histologic changes in obese patients after laparoscopic bariatric surgery

    Transiliac bone biopsies will be performed in a approximately 15% of patients at baseline and after 24 months. The following parameters will be measured: bone volume (BV/TV), bone surface (BS/BV), osteoblast surface (OS/BS), trabecular number (TbN), trabecular thickness (TbTh, trabecular separation (Tb.sp), mineralized surface (MS/BS), mineral apposition rate (MAR) Differences will be evaluated on the outcome with/without daily calcium (500mg) and weekly vitamin D (16.000 IU colecalciferol) supplementation

    Time frame: baseline and after 24 months

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Study locations

1 site
  • Medical University Vienna
    Vienna, 1060, Austria
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References and documents

Publications

  • Muschitz C, Kocijan R, Haschka J, Zendeli A, Pirker T, Geiger C, Muller A, Tschinder B, Kocijan A, Marterer C, Nia A, Muschitz GK, Resch H, Pietschmann P. The Impact of Vitamin D, Calcium, Protein Supplementation, and Physical Exercise on Bone Metabolism After Bariatric Surgery: The BABS Study. J Bone Miner Res. 2016 Mar;31(3):672-82. doi: 10.1002/jbmr.2707. Epub 2015 Sep 30. PubMed 26350034 ↗
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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Aug 25, 2014, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT01739855
Lead sponsor
Medical University of Vienna
Responsible party
Dr. Christian Muschitz (Senior Consultant for Internal Medicine, Medical University of Vienna) — Principal investigator
First posted
Dec 4, 2012
Start date
Nov 2012
Primary completion
Jul 2014
Completion
Aug 2014
Last update
Aug 25, 2014

Study contacts

Christian Muschitz, M.D.
principal investigator · Medical University Vienna - Austria

Oversight

Data monitoring committee
Yes
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Aug 2014. You cannot join it, but the record below documents what was studied.

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