Is the magnesium phosphate ratio a predictor of arrhythmia in patients undergoing hemodialysis?
Authors: YURDAM Ferhat , TATLI Muhittin Doruk 
Published: January 2023

Aim: Sudden death due to coronary artery disease, heart failure, arrhythmia or hyperkalemia constitutes the majority of cardiovascular causes in patients with end-stage renal disease. Magnesium plays an important role in many processes that regulate cardiovascular functions such as endothelial function, regulation of vascular tone and myocardial excitability. In addition, hyperphosphatemia is very common in patients with end-stage renal disease and is associated with an increased risk of mortality in hemodialysis patients. Our aim in this study; to determine the role of Mg/PO4 ratio in predicting arrhythmia in patients with end-stage renal disease receiving hemodialysis.Material and Method: A total of 103 consecutive patients admitted to the cardiology outpatient clinic and receiving hemodialysis for chronic renal failure were included in the study. Between January 2018 and October 2022, patients monitored with 24-hour rhythm holter ECG were recruited. Patients were analyzed by dividing into 2 groups as those with arrhythmia detected in 24-hour rhythm Holter ECG (group 1: 51 patients) and those without (group 2: 52 patients). Result: The mean age of the patients in the study was significantly higher in group 1 compared to group 2 (66.96±10.27 and 62.21±10.50, p=0.02, respectively). When the 24-hour rhythm Holter ECGs of the patients were examined, the most common arrhythmia was ventricular extrasystole with a rate of 18.4% (n=19), and paroxysmal AF was the second with a rate of 9.7% (n=10). In the univariate regression analysis we performed for arrhythmia predictivity in patients receiving hemodialysis; age (OR: 1.046; 95%CI: 1.005-1.088, p=0.02), LVEF (OR: 0.941; 95%CI: 0.895-0.989, p=0.01), mid-severe MR (OR: 0.553; 95%CI: 0.215-1.424, p=0.22), Na (OR: 1.119; 95%CI: 0.967-1.294, p=0.13), Hemoglobin (OR: 0.872; 95%CI: 0.710-1.069, p=0.18), total cholesterol (OR: 1.006; 95%CI: 0.997-1.016, p=0.19), LDL (OR: 1.012; 95%CI: 0.998-1.026, p=0.10), Mg (OR: 0.117; 95%CI: 0.015- 0.941, p=0.04), PO4 (OR: 1.664; 95%CI: 1.093-2.532, p=0.01), Mg/PO4 ratio (OR: 0.002; 95%CI: 0.000-0.104, p=0.002) detected as arrhythmia predictors. In the multivariate regression analysis, independent predictors for the presence of arrhythmia were determined using 2 different models. In the model 1; age (OR: 0.993; 95%CI: 0.956 1.031, p=0.70), LVEF (OR: 0.955; 95%CI: 0.916-0.994, p=0.026), Mg (OR: 0.136; 95%CI: 0.014-1.308), p=0.08), PO4 (OR: 1.545; 95%CI: 0.989- 2.414, p=0.056) (Table 6). In the model 2; age (OR: 0.988; 95%CI: 0.951-1.026, p=52), LVEF (OR: 0.955; 95%CI: 0.917-0.995, p=0.029), Mg/PO4 ratio (OR: 0.002, 95%CI: 0.000-0.101 p=0.002) was detected independent predictors for the presence of arrhythmia. ROC analysis (Figure) showed that LVEF&lt;54.5%, with 64% sensitivity and 53% specificity ([AUC]: 0.666, 95% CI: 0.560-0.772, p=0.004), Mg/PO4 ratio&lt;0.45, with 64% sensitivity and 65% specificity ([AUC]: 0.674, 95% CI: 0.570-0.778, p=0.002), predicts arrhythmia in hemodialysis patients Conclusion: In our study, it was concluded that the Mg/P ratio, which can be calculated simply, is a predictor of arrhythmia in hemodialysis patients.