Correlation of serum magnesium with serum parathormone levels in patients on regular hemodialysis.

Secondary hyperparathyroidism (SHPT) is a common, important, and treatable complication of end-stage renal disease. This study was conducted to investigate the role of serum magnesium (Mg) in regulating the secretion of parathyroid hormone (PTH) by the parathyroid gland in patients on maintenance hemodialysis (HD). Pre-dialysis serum levels of calcium (Ca), phosphorus (P), Mg, alkaline phosphatase (ALP), intact serum PTH (iPTH), serum 25-hydroxy Vitamin D (25-OH Vit D) and plasma bicarbonate (HCO3) were measured. The Urea Reduction Rate as well as duration and dosage of HD treatment were noted. Our study did not show any significant correlation between serum Mg levels and duration of HD treatment, levels of serum ALP, and plasma HCO3, Ca and P. An inverse correlation, albeit insignificant, was found between the serum Mg levels and iPTH (r = -0.30 p = 0.079); also, a significant positive correlation was found between serum Mg levels and serum 25-OH Vit D levels (r = 0.40 p = 0.009). Our findings are in agreement with previous data, which suggest that factors other than serum Mg are more important in the regulation of PTH secretion in HD patients. A positive and strong association between serum Mg with 25-OH Vit D needs to be studied in greater detail.