Serum magnesium level in maintenance hemodialysis and cardiovascular calcification

Background
Patients with chronic kidney disease have a high prevalence of vascular calcification, and cardiovascular disease is the leading cause of death. Magnesium (Mg) is a natural calcium antagonist and many studies have shown that low circulating levels of Mg are associated with vascular calcification.
Aim of the work
The aim of the study was to assess the relationship between serum Mg levels and vascular calcification in chronic hemodialysis (HD) patients.
Patients and methods
A cross-sectional study conducted on 60 patients with end-stage renal disease on regular HD in Al-Zahraa University Hospital (group I) compared with 30 healthy controls (group II), from June to December 2017. Patients with evidence of infection, chronic diarrhea, ileostomy, and those receiving Mg-based phosphate binders were excluded from the study. All studied groups were submitted to clinical examination, renal function, lipid profile, serum albumen, calcium, phosphorus, intact parathyroid hormone, Mg, carotid duplex, echocardiography, ECG, and lateral view plain abdominal radiograph.
Results
There were highly significant differences regarding Mg and carotid intimal medial thickness (CIMT) in group I compared with group II: 1.51±0.28, 0.89±0.30 and 2.47±0.18, 0.45±0.08 respectively, <0.001. Echocardiographic findings showed calcified mitral and aortic valves in 12 (20%) patients and calcified abdominal aorta by abdominal X-ray radiograph in 20 (33.33%) patients. There were highly significant negative correlation between serum Mg and CIMT and abdominal aortic calcification in group I.
Conclusion
The patients on maintenance HD have lower serum Mg levels. It was associated with increased CIMT and vascular calcification if compared with healthy group and concomitant use of proton pump inhibitors may aggravate this hypomagnesemia. So serum Mg level in maintenance HD patients could be a potential biomarker for cardiovascular calcifications.