The effect of magnesium supplementation on vascular calcification in chronic kidney disease—a randomised clinical trial (MAGiCAL-CKD): essential study design and rationale

BMJ Open
Q1
Jun 2017
Citations:30
Influential Citations:2
Interventional (Human) Studies
87
S2 IconPDF Icon

Enhanced Details

Methods
Randomised, double-blind, placebo-controlled multicentre trial conducted at 10 nephrology sites in Denmark and Norway; adults with CKD stage 3b-4 at increased risk of vascular calcification based on serum Mg and phosphate; 250 participants randomized 1:1; stratified by enrolment site and diabetes.
Intervention
Oral slow-release magnesium hydroxide, 360 mg per tablet, 1 tablet taken twice daily (total 720 mg per day; 30 mmol elemental Mg per day) for 52 weeks; compared with matching placebo.
Results
No results reported yet; trial designed to determine whether 52 weeks of oral magnesium hydroxide supplementation can prevent progression of coronary artery calcification in predialysis CKD (stage 3b-4). Primary endpoint is change in CAC score (Agatston) from baseline to 52 weeks. Secondary endpoints include changes in PWV, PWA, BMD, mineral metabolism markers, and incidence of cardiovascular/renal events; a 5-year follow-up is planned to assess longer-term outcomes.
Limitations
CAC is a surrogate endpoint for cardiovascular disease; not powered to assess cardiovascular events or mortality. Cannot differentiate intimal vs. medial calcification with CAC (Agatston score). Study includes only CKD stage 3b-4 (not stage 5); extrapolation to more severe CKD uncertain. CF-PWV and related measurements are performed only in a subset; long-term safety in very low eGFR not established.

Abstract

Introduction Chronic kidney disease (CKD) is associated with an increased risk of cardiovascular disease and mortality, which is thought to be caused by increased propensity towards vascular calcification (VC). Magnesium (Mg) inhibits phosphate-induc...