Introduction: Low serum magnesium (Mg) is associated with an increased incidence of atrial and ventricular arrhythmias. A richer phenotyping of arrhythmia indices, such as burden or frequency, may provide etiologic insights. Objectives: To evaluate cross-sectional associations of serum Mg with burden of atrial arrhythmias [atrial fibrillation (AF), premature atrial contractions (PAC), supraventricular tachycardia (SVT)], and ventricular arrhythmias [premature ventricular contractions (PVC), non-sustained ventricular tachycardia (NSVT)] over 2-weeks of ECG monitoring. Methods: We included 2513 ARIC Study visit 6 (2016–2017) participants who wore the Zio XT Patch—a leadless, ambulatory ECG-monitor—for up to 2-weeks. Serum Mg was modeled categorically and continuously. AF burden was categorized as intermittent or continuous based on the percent of analyzable time spent in AF. Other arrhythmia burdens were defined by the average number of abnormal beats per day. Linear regression was used for continuous outcomes; logistic and multinomial regression were used for categorical outcomes. Results: Participants were mean ± SD age 79 ± 5 years, 58% were women and 25% black. Mean serum Mg was 0.82 ± 0.08 mmol/L and 19% had hypomagnesemia (<0.75 mmol/L). Serum Mg was inversely associated with PVC burden and continuous AF. The AF association was no longer statistically significant with further adjustment for traditional lifestyle risk factors, only the association with PVC burden remained significant. There were no associations between serum Mg and other arrhythmias examined. Conclusions: In this community-based cohort of older adults, we found little evidence of independent cross-sectional associations between serum Mg and arrhythmia burden.
|Original language||English (US)|
|Number of pages||6|
|Journal||Journal of Electrocardiology|
|State||Published - Sep 1 2020|
Bibliographical noteFunding Information:
The ARIC study has been funded in whole or in part with Federal funds from the National Heart, Lung, and Blood Institute, National Institutes of Health, Department of Health and Human Services , under Contract nos. ( HHSN268201700001I , HHSN268201700002I , HHSN268201700003I , HHSN268201700005I , HHSN268201700004I ). This work was also supported by grants from the NIH/NHLBI [ R01HL126637-01A1 (LYC), T32HL007779 (MRR), T32HL007024 (MRR), K24HL148521 (AA)], the American Heart Association [ 16EIA26410001 (AA)], and the NIH/NIDDK [ K24DK106414 (ES)] . Reagents for magnesium and potassium were donated by Roche Diagnostics.
- Atrial arrhythmias
- Continuous electrographic monitoring
- Older adults
- Serum magnesium
- Ventricular arrhythmias