Serum Magnesium Not Found to Be Associated With Arrhythmia Burden in Older Adults

Serum levels of magnesium (Mg) may not be associated with arrhythmia burden in older adults, according to from the results of a community-based, cross-sectional cohort study published in the Journal of Electrocardiology.

In the Atherosclerosis Risk In Communities (ARIC) study which began in 1987, patients (n=2513; ages 45-64 years; mean age, 79±5 years; 58% women) living in Minnesota, North Carolina, Mississippi, and Maryland were enrolled. Data for this study were collected during a follow-up visit which took place between 2016 and 2017. Participants had electrocardiograph monitoring for up to 2 weeks and their serum Mg levels were assessed.

In this cohort, the mean serum Mg level was 0.82±0.08 mmol/L, and the median duration of electrocardiograph monitoring was 13.7 days (interquartile range [IQR], 12.7-13.9 days).

Participants who had low vs normal serum Mg levels (ie, <0.75 mmol/L and 0.85-0.95 mmol/L, respectively) took more antihypertensive (91.0% vs 69.9%, respectively) and proton pump inhibitor (34.7% vs 21.2%, respectively) medications.

After adjusting for demographic parameters, participants with Mg levels <0.75 mmol/L vs ≥0.75 mmol/L had higher odds of exhibiting continuous atrial fibrillation (odds ratio [OR], 1.90; 95% CI, 1.17-3.06).

Using a model adjusted for demographic factors and comorbidities, every 0.1 mmol/L decrease in serum Mg level was associated with 1.27-fold higher odds of continuous atrial fibrillation (95% CI, 1.02-1.57).

Little evidence for a relationship between serum Mg level and premature atrial contractions, supraventricular tachycardia, or non-sustained ventricular tachycardia was observed.

Study limitations include its observational nature.

“Future research should test whether serum Mg may be a more robust risk factor for arrhythmia burden in younger adults,” noted the study authors.

Reference

Rooney M R, Lutsey P L, Alonso A, et al. Serum magnesium and burden of atrial and ventricular arrhythmias: The Atherosclerosis Risk in Communities (ARIC) Study. J Electrocardiol. 2020;62:20-25. doi:10.1016/j.jelectrocard.2020.07.008