Magnesium Treatment on Vitamin D Metabolism in Participants Completed Personalized Prevention of Colorectal Cancer Trial

Vanderbilt University Medical Center

Status: Completed

Conditions: Colorectal Cancer

Treatments: Dietary Supplement: Placebo; Dietary Supplement: Magnesium glycinate

Study type: Interventional

Funder types: Other

Identifiers

NCT03265483

100106b

Details and patient eligibility

About

One striking observation is that a large portion of the inter-person variation in serum 25-hydroxyvitamin D (25(OH)D) levels is unexplained. In vitro and in vivo studies indicate vitamin D synthesizing and metabolizing enzymes are Mg-dependent. Magnesium (Mg) supplementation substantially reversed the resistance to vitamin D treatment in patients with magnesium-dependent vitamin-D-resistant rickets. The investigators reported in 2013 from observational studies conducted in the general US population that Mg intake significantly interacted with vitamin D intake in affecting vitamin D status as well as interacted with serum 25(OH)D in risk of cardiovascular disease mortality and, maybe, colorectal cancer mortality. The potential interaction between Mg and vitamin D was supported by two subsequent studies, including a Finnish cohort study and a mouse study.

In the parent study (Personalized Prevention of Colorectal Cancer Trial, NCT01105169), the investigators proposed to measure blood concentration of total 25(OH)D as a secondary aim using Elisa approach. However, following the novel finding of Mg-vitamin D interaction published by the investigators in 2013, they submitted a separate grant application to NCI which was funded in 2014. In the new study, the investigators proposed to use a LC-MS approach, which is more accurate and specific than an Elisa method, to measure 5 vitamin D metabolites. This new ancillary study allows the investigators to evaluate whether Mg supplementation differentially affects vitamin D synthesis and metabolism dependent on baseline serum 25(OH)D levels using existing biospecimens collected in our double-blind placebo-controlled randomized chemoprevention trial.

Enrollment: 180 patients

Sex: All

Ages: 40 to 85 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

1. Participants from our parent study (Personalized Prevention of Colorectal Cancer Trial, NCT#01105169, IRB#100106);
2. Participants who had completed the above study before the time of the sample selection (October 2015);
3. Participants consent to store/share samples for future research in colorectal tumors.

Exclusion criteria

1. Participants cannot provide their blood samples in the parent study.

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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180 participants in 2 patient groups, including a placebo group

Magnesium treatment

Active Comparator group

Description:

Participants will be assigned to magnesium glycinate

Treatment:

Dietary Supplement: Magnesium glycinate

Placebo

Placebo Comparator group

Description:

Participants will be assigned to placebo group

Treatment:

Dietary Supplement: Placebo