title: Determinants of hypomagnesemia in patients with type 2 diabetes mellitus.
abstract: BACKGROUND
  Hypomagnesemia (plasma magnesium (Mg2+) concentration <0.7 mmol/L) has been described in patients with type 2 diabetes. Polypharmacy is inevitable when treating a complex disease such as type 2 diabetes and could explain disturbances in the plasma Mg2+concentration. In this study, we aimed to establish the extent of hypomagnesemia in a cohort of type 2 diabetes patients and to identify the determinants of plasma Mg2+levels.
  
  
  METHODS
  Patient data and samples of 395 type 2 diabetes patients were investigated. Plasma Mg2+concentrations were measured using a spectrophotometric assay. Using Pearson correlation analyses, variables were correlated to plasma Mg2+levels. After excluding confounding variables, all parameters correlating (P < 0.1) with plasma Mg2+were included in a stepwise backward regression model.
  
  
  RESULTS
  The mean plasma Mg2+concentration in this cohort was 0.74 ± 0.10 mmol/L. In total, 121 patients (30.6%) suffered from hypomagnesemia. Both plasma triglyceride (r = -0.273, P < 0.001) and actual glucose levels (r = -0.231, P < 0.001) negatively correlated with the plasma Mg2+concentration. Patients using metformin (n = 251, 62%), proton pump inhibitors (n = 179, 45%) or β-adrenergic receptor agonists (n = 31, 8%) displayed reduced plasma Mg2+levels. Insulin use (n = 299, 76%) positively correlated with plasma Mg2+levels. The model predicted (R2) 20% of all variance in the plasma Mg2+concentration.
  
  
  CONCLUSIONS
  Hypomagnesemia is highly prevalent in type 2 diabetes patients. Plasma triglycerides and glucose levels are major determinants of the plasma Mg2+concentration, whereas only a minor part (<10%) of hypomagnesemia can be explained by drug intake, excluding polypharmacy as a major cause for hypomagnesemia in type 2 diabetes.
authors.affiliation: Departments of Physiology.
authors.forename: Steef
authors.initials: S
authors.lastname: Kurstjens
authors.affiliation: Departments of Physiology.
authors.forename: Jeroen H F
authors.initials: JH
authors.lastname: de Baaij
authors.affiliation: Departments of Physiology.
authors.forename: Hacene
authors.initials: H
authors.lastname: Bouras
authors.affiliation: Departments of Physiology.
authors.forename: René J M
authors.initials: RJ
authors.lastname: Bindels
authors.affiliation: Internal MedicineRadboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Cees J J
authors.initials: CJ
authors.lastname: Tack
authors.affiliation: Departments of Physiology joost.hoenderop@radboudumc.nl.
authors.forename: Joost G J
authors.initials: JG
authors.lastname: Hoenderop
mesh_terms: D000368:Aged; D001786:Blood Glucose / Q000187:drug effects; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000188:drug therapy; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use; D007328:Insulin / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use; D008274:Magnesium / Q000097:blood*; D008297:Male; D008687:Metformin / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use; D008875:Middle Aged; D014280:Triglycerides / Q000097:blood
chemical_list: D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin; D014280:Triglycerides; D008687:Metformin; D008274:Magnesium