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.
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