Correlation Between Serum Parathormone Levels With Urinary Magnesium Excretion In Patients With Non-Dialytic Chronic Kidney Disease

Abstract

Background: Disorders of mineral metabolism occur in most patients with chronic kidney disease (CKD). The aim of this work was to correlate serum parathyroid hormone (PTH) levels with urinary magnesium excretion in patients with non-dialysis CKD.Methods: Cross-sectional study with patients with CKD undergoing non-dialysis treatment in stages 3A, 3B and 4. Concentrations of creatinine, magnesium, calcium, phosphorus, parathyroid hormone (PTH), 25-hydroxyvitamin D [25(OH)D] and alkaline phosphatase (ALP) were determined in blood samples. The assessment of urinary magnesium levels was performed by means of total daily excretion and by the excretion fraction (FEMg). Results: The study evaluated 163 patients with a mean age of 60.7 ± 11.7 years and 51.0% were male. In the highest quartile of PTH (> 89.5pg / ml), the mean levels of FEMg and ALP were higher (p <0.05), as well as the levels of serum calcium and eGFR were lower (p <0.05). In the unadjusted regression analysis, the following variables were related to serum PTH levels: FEMg (odds ratio (OR) = 1.12; 95% confidence intervals (CI): 1.02–1.23), Calcium (OR = 0.45; 95% CI: 0.22-0.90), ALP (OR = 1.02; 95% CI: 1.00-1.03) and eTFG (OR = 0.92; 95% CI: 1.00-1.03). After an adjusted analysis, only one FEMg and ALP will remain correlated with PTH. Conclusion: In patients with non-dialysis CKD, with higher levels of PTH, higher mean columns of ALP and FEMg, and lower levels of serum calcium and eGFR. FEMg and ALP were some variables that remained associated with PTH.