Investigation of the Optimal Calcium Supplement Following Roux-en-Y Gastric Bypass

Investigation of the Optimal Calcium Supplement Following Roux-en-Y Gastric Bypass in Order to Treat Secondary Hyperparathyroidism: A Clinical Randomized Trial

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT02830789

Enrollment

Registered

2016-07-13

Start date

2016-12-31

Completion date

2017-05-31

Last updated

2017-06-26

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Roux-en-Y Gastric Bypass, Hyperparathyroidism, Secondary

Brief summary

This study investigates whether calcium citrate or calcium carbonate are the optimal supplement to treat secondary hyperparathyroidism following Roux-en-Y gastric bypass operation. Half of the participants will be randomized to receive calcium citrate, while the other half will receive calcium carbonate. The study will be double blinded.

Interventions

DIETARY_SUPPLEMENTCalcium Carbonate

DIETARY_SUPPLEMENTCalcium Citrate

DIETARY_SUPPLEMENTPlacebo

Tablet manufactured to mimic a calcium carbonate tablet

PROCEDURERoux-en-Y gastric bypass

Roux-en-Y gastric bypass surgery at least 12 months before study inclusion

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

TREATMENT

Masking

DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender

ALL

Age

20 Years to 70 Years

Healthy volunteers

Inclusion criteria

* Roux-en-Y gastric bypass operation ≥12 months ago * Parathyroid hormone \> 6.9 pmol/l * Vitamin D \> 50 nmol/l * P-Calcium \[1.18-1.32\] mmol/l

Exclusion criteria

* Liver disease * Renal disease * Hypercalcemia * Untreated thyroid disease * Parathyroid disease except secondary hyperparathyroidism * Use of diuretics, bisphosphonates, calcitonin, teriparatide, oral corticosteroids, anabolic steroids, calcimimetics, lithium, strontium, denosumab or anticonvulsants within 1 year of inclusion * abusing alcohol

Design outcomes

Primary

Measure	Time frame
Parathyroid Hormone	Change from baseline at 6 weeks and 12 weeks

Secondary

Measure	Time frame
P-magnesium	Change from baseline at 6 weeks and 12 weeks
P-phosphate	Change from baseline at 6 weeks and 12 weeks
P-25-OH-vitamin D	Change from baseline at 6 weeks and 12 weeks
P-calcitriol	Change from baseline at 6 weeks and 12 weeks
P-24,25-(OH)2-vitamin D	Change from baseline at 6 weeks and 12 weeks
Se-ion-calcium	Change from baseline at 6 weeks and 12 weeks
Procollagen type 1 N-terminal propeptide (P1NP)	Change from baseline at 6 weeks and 12 weeks
P-bone specific alkaline phosphatase	Change from baseline at 6 weeks and 12 weeks
Cross-linked C-telopeptide (CTX)	Change from baseline at 6 weeks and 12 weeks
24h U-calcium	Change from baseline at 12 weeks
24h U-phosphate	Change from baseline at 12 weeks
Vitamin D binding protein	Change from baseline at 6 weeks and 12 weeks

Countries

Denmark

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026