Magnesium Replacement and Hyperglycemia After Kidney Transplantation

Oslo University Hospital40 enrolled

Overview

The insulin receptor is dependent on magnesium and hypomagnesemia is associated with increased insulin resistance and decreased insulin secretion and action. Recent data suggest that hypomagnesemia may play a role in development of type 2 diabetes. Kidney transplantation patients have low plasma magnesium levels, partly due to treatment with calcineurin inhibitors. However, the role of magnesium in the development of post-transplant diabetes mellitus (PTDM) is unclear. The present study addresses, whether hypomagnesemia is feasible to reverse by oral administration of magnesium. The investigators wish to investigate whether oral magnesium supplementation is sufficient to increase magnesium levels in kidney transplant recipients, and if supplementation improves glycemic parameters as measured by an oral glucose tolerance test (OGTT).

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Enrollment

Conditions

Hypomagnesemia Kidney Transplantation

Interventions

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Kidney transplant recipients more than one year after transplantation * Hypomagnesemia (\< 0.7 mmol/L) * Age ≥ 18 years and able to give written informed consent Exclusion Criteria: * Current treatment with magnesium containing medication or supplements * Current medical treatment for diabetes * Conditions impairing magnesium absorption from the gastrointestinal tract (e.g. short bowel syndrome, chronic pancreatitis) * Subjects with primary non-graft function and subjects with need of dialysis therapy \>2 months or graftectomy at any time point after transplantation

Outcomes

Primary Outcomes

Magnesium retension at loading test

Difference in magnesium retension at magnesium loading test between before and after oral treatment. Retension defined as percentage of magnesium retained from intravenous magnesium sulphate.

Time frame: 24 weeks

Secondary Outcomes

Plasma glucose (mmol/L)

Change of fasting plasma glucose (mmol/L) between start and the end of supplementation.

Time frame: Baseline (Before magnesium loading tests)

Insulin (mg/kg/min)

Change of insulin (mg/kg/min) in OGTT (after 2 hours) between start and the end of supplementation.

Time frame: 2 hours oral glucose tolerance test

C-peptide (nmol/L)

Change of C-peptide (nmol/L) in OGTT (after 2 hours) between start and the end of supplementation.