Association of Serum Magnesium and Blood Pressure in Patients with Hypertensive Crises: A Retrospective Cohort Study

Abstract

\n Background: The role of magnesium in blood pressure has been studied among hypertensive patients, however, no study has explored the role of magnesium in hypertensive crises. The primary objective of this study is to evaluate the relationship between serum magnesium and blood pressure in patients with hypertensive crises.\nMethods: This study is a single-center, retrospective, chart review, cohort study of patients with hypertensive crises. Patients were included in the study cohort if they were eighteen years of age or older with an international classification disease ninth revision (ICD-9) code of 401.9 (hypertensive crises: emergency or urgency) and a documented magnesium level on their electronic medical record. The primary outcome of the study was to assess the correlation between serum magnesium on blood pressure (systolic blood pressure and diastolic blood pressure) in patients with hypertensive crises. The secondary outcomes were to assess the association between serum calcium, corrected calcium, and serum potassium on blood pressure in patients with hypertensive crises and to determine the effects of covariates in modulating the relationship between serum magnesium and blood pressure.\nResults: Two hundred and ninety-three patients were included in the study. The primary outcome result showed that serum magnesium was positively correlated with systolic blood pressure (r=0.143, p=0.014), but not diastolic blood pressure. Serum calcium was also found to be positively correlated with systolic blood pressure, but not diastolic blood pressure. After adjusting for covariates in the solution for fixed effects analysis, serum magnesium, serum calcium, corrected calcium, and use of home proton pump inhibitors were correlated with systolic blood pressure at crises; while age, serum calcium, and corrected calcium were significantly correlated with diastolic blood pressure at crises.\nConclusion: This study found a significant positive association between magnesium and systolic blood pressure, but not diastolic blood pressure among patients with hypertensive crises. This positive association of serum magnesium with systolic blood pressure was maintained after adjusting for covariates. This study findings suggests a potential role of magnesium in blood pressure among patients with hypertensive crises. Future studies should evaluate the role of serum magnesium modifying therapies in controlling blood pressure in patients with hypertensive crises.