JACC Asia. 2026 Jul;6(7):1193-1205. doi: 10.1016/j.jacasi.2026.04.041.
ABSTRACT
BACKGROUND: Atrial fibrillation (AF) involves adaptive immune imbalance, particularly within T-cell subsets, yet systematic profiles in Asian cohorts remain limited.
OBJECTIVES: The authors aimed to characterize peripheral adaptive immune dysregulation in Asian patients with AF and to examine heterogeneity across AF subtypes and demographics.
METHODS: In this case-control study of 173 AF patients and 87 controls, cases were adults with electrocardiogram-confirmed AF recruited from the hospital; controls were participants undergoing routine examinations who were in sinus rhythm and had no structural heart disease. T-cell subsets were quantified by flow cytometry and serum cytokines by enzyme-linked immunosorbent assay. Multivariable logistic models, adjusted for left atrial diameter, left ventricular ejection fraction, and neutrophil-to-lymphocyte ratio, assessed associations of immune indices with AF.
RESULTS: AF was characterized by higher T helper (Th)1 and Th17 cell counts and percentages, with no significant difference in T regulatory cells (Tregs); accordingly, Th1/Treg and Th17/Treg ratios were higher (all P < 0.05). Systemic inflammatory markers (high-sensitivity C-reactive protein, interleukin-6) and effector cytokines (interferon-γ, interleukin-17A) were elevated in AF. In multivariable models, higher Th17 count (OR: 3.30; 95% CI: 1.27-8.53; P = 0.014) and Th1/Treg (OR: 4.20; 95% CI: 1.72-10.24; P = 0.002) were associated with AF. Immune alterations appeared broader in paroxysmal AF, whereas persistent AF showed a more selective Th1/Treg imbalance. Patterns were generally consistent across age, sex, and body mass index strata in exploratory analyses.
CONCLUSIONS: In this Asian cohort, AF was associated with an adaptive immune shift toward Th1/Th17 relative to Treg, with subtype-specific patterns. These associations are hypothesis-generating and warrant prospective, tissue-level studies to clarify mechanisms and clinical relevance.
PMID:42412701 | DOI:10.1016/j.jacasi.2026.04.041