Systemic Inflammation Is Associated with Resting Premature Atrial and Ventricular Contractions in American Older Adults.

Prior studies have demonstrated links between systemic inflammation and cardiac arrhythmias. However, evidence on the association between inflammatory biomarkers and resting premature atrial contractions (PACs) or premature ventricular contractions (PVCs) in a national sample of older adults remains limited. Using biomarker data from the Midlife in the United States (MIDUS 3) study (2017-2022), we conducted non-parametric univariate analyses to assess associations between inflammatory markers-specifically, interleukin (IL)-6, IL-8, IL-10, tumor necrosis factor-α (TNF)-α, C-reactive protein (CRP), and fibrinogen-and baseline electrocardiographic (ECG) findings categorized as normal, PVCs, or PACs. We conducted a subsequent multivariate analysis of covariance adjusted for age, waist-hip ratio (WHR), and creatinine, the only confounders showing significant associations. A total of 699 participants were included, 395 (57%) of whom were women, with a mean age of 65.7 years (standard deviation, 9.6 years). The Kruskal-Wallis tests demonstrated significant associations of ECG pattern with IL-6 (median, normal 0.98 vs. PVCs 1.06 vs. PACs 1.40; <i>P</i> = .006) and IL-8 (12.4 vs. 13.99 vs. 13.13; <i>P</i> = .028). No significant associations were found for IL-10, TNF-α, CRP, or fibrinogen (<i>P</i> > .05). After adjustment for age, WHR, and creatinine, the ECG pattern remained significantly associated with IL-6 and IL-8 (<i>P</i> = .034). Elevated IL-6 and IL-8 levels are associated with resting PVCs and PACs in older adults. WHR and renal function also represent significant related factors that warrant consideration in future pathophysiological research.