Serum magnesium levels as a predictor of coronary artery stenosis and their association with oxidative stress biomarkers.

Abstract

Background: To investigate the association between serum magnesium (Mg) levels and the presence of coronary artery stenosis, as well as their correlation with oxidative stress biomarkers malondialdehyde (MDA) and superoxide dismutase (SOD).

Methods: In this retrospective study, a total of 42 patients diagnosed with coronary artery stenosis at the First Affiliated Hospital of Xinjiang Medical University between January 2022 and October 2024 were included as the coronary artery experimental group, while another 42 cases with no significant stenosis confirmed by coronary angiography during the same period served as the control group. Demographic and clinical characteristics, as well as serum Mg levels and oxidative stress markers were compared between the two groups. The correlations between serum Mg levels and both coronary artery stenosis and oxidative stress factors (MDA and SOD) were analyzed using the Spearman rank correlation coefficient. Receiver operating characteristic (ROC) curve was used to analyze the diagnostic performance of serum Mg levels on coronary artery stenosis.

Results: There were no significant differences in the baseline demographic characteristics between the two groups (all P>0.05), including age, gender distribution, body mass index (BMI), educational background, smoking and alcohol consumption history, systolic blood pressure (SBP), diastolic blood pressure (DBP), DM course, fasting plasma glucose (FPG), glycated hemoglobin (GHb), triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), creatinine (Cr), and blood urea nitrogen (BUN). The stenosis group had significantly lower serum Mg levels (1.57±0.37 vs. 2.02±0.33 mmol/L, P<0.001) and higher SOD (86.11±21.59 vs. 59.02±17.36 U/mL, P<0.001), while MDA was elevated in controls (24.52±8.33 vs. 18.82±6.37 nmol/mL, P=0.001). The ROC analysis of serum Mg levels for predicting coronary artery stenosis yielded an area under the curve (AUC) of 0.825 (95% CI: 0.757-0.923), with an optimal cutoff value of 1.88 mmol/L (standard error: 0.3265), achieving a sensitivity of 80% and specificity of 75%. Spearman correlation analysis demonstrated a negative association between Mg and MDA (r=-0.506, P=0.041) and a positive association with SOD (r=0.288, P=0.008) in patients with coronary stenosis.

Conclusions: Lower serum magnesium levels are significantly associated with an increased risk of coronary artery stenosis. Moreover, reduced serum Mg correlates with elevated MDA levels and decreased SOD activity, indicating enhanced oxidative stress.