TY - JOUR
T1 - Inflammation and day-to-day occurrence of atrial fibrillation
AU - Hessellund, August Krebs
AU - Kongebro, Emilie Katrine
AU - Haugan, Ketil Jørgen
AU - Xing, Lucas Yixi
AU - Vad, Oliver Bundgaard
AU - Graff, Claus
AU - Spona, Daniel Camillo
AU - Baadsgaard, Jonas Alexander
AU - Højberg, Søren
AU - Brandes, Axel
AU - Køber, Lars
AU - Frikke-Schmidt, Ruth
AU - Svendsen, Jesper Hastrup
AU - Diederichsen, Søren Zöga
N1 - © The Author(s) 2026. Published by Oxford University Press on behalf of the European Society of Cardiology.
PY - 2026/4/8
Y1 - 2026/4/8
N2 - AIMS: Inflammation is central in atrial fibrillation (AF) pathophysiology, but the temporal association between inflammatory activity and AF remains uncertain. This study investigated the day-to-day relationship between plasma C-reactive protein (CRP) levels and AF occurrence in continuously monitored individuals.METHODS AND RESULTS: Post hoc analysis of the LOOP study randomizing participants with stroke risk factors to implantable loop recorder (ILR) screening (n = 1501) or usual care. ILR raw data were linked to blood samples collected within 1 day. The outcome was AF episodes lasting ≥60 min. Associations were examined using generalized and linear mixed models and as a self-controlled case series (SCCS). ILR and CRP data were available for 1065 participants combining >1.2 million days of heart rhythm monitoring (including ∼40 000 days with AF) with >7000 CRP measurements. CRP was higher during days with AF (geometric mean 8.37 [7.11-9.86] mg/L) vs. non-AF days (4.02 [3.71-4.35] mg/L). Each doubling of CRP was associated with 36% higher odds of AF (adjusted odds ratio [aOR] 1.36 [1.26-1.47]). Compared with CRP ≤3 mg/L, the odds of AF increased for CRP >10-50 and >50 mg/L (aOR 3.50 [2.18-5.60] and 5.75 [3.48-9.50], respectively). In SCCS analyses, CRP >10 mg/L was associated with higher incidence of AF compared to lower levels (incidence rate ratio 2.41 [1.53-3.80]).CONCLUSION: This exploratory study found a temporal and dose-response relationship between CRP levels and AF occurrence, supporting inflammation as an acute trigger and underscoring the need to evaluate inflammatory markers as potential targets in AF management.TRIAL REGISTRATION: ClinicalTrials.gov, identifier: NCT02036450.
AB - AIMS: Inflammation is central in atrial fibrillation (AF) pathophysiology, but the temporal association between inflammatory activity and AF remains uncertain. This study investigated the day-to-day relationship between plasma C-reactive protein (CRP) levels and AF occurrence in continuously monitored individuals.METHODS AND RESULTS: Post hoc analysis of the LOOP study randomizing participants with stroke risk factors to implantable loop recorder (ILR) screening (n = 1501) or usual care. ILR raw data were linked to blood samples collected within 1 day. The outcome was AF episodes lasting ≥60 min. Associations were examined using generalized and linear mixed models and as a self-controlled case series (SCCS). ILR and CRP data were available for 1065 participants combining >1.2 million days of heart rhythm monitoring (including ∼40 000 days with AF) with >7000 CRP measurements. CRP was higher during days with AF (geometric mean 8.37 [7.11-9.86] mg/L) vs. non-AF days (4.02 [3.71-4.35] mg/L). Each doubling of CRP was associated with 36% higher odds of AF (adjusted odds ratio [aOR] 1.36 [1.26-1.47]). Compared with CRP ≤3 mg/L, the odds of AF increased for CRP >10-50 and >50 mg/L (aOR 3.50 [2.18-5.60] and 5.75 [3.48-9.50], respectively). In SCCS analyses, CRP >10 mg/L was associated with higher incidence of AF compared to lower levels (incidence rate ratio 2.41 [1.53-3.80]).CONCLUSION: This exploratory study found a temporal and dose-response relationship between CRP levels and AF occurrence, supporting inflammation as an acute trigger and underscoring the need to evaluate inflammatory markers as potential targets in AF management.TRIAL REGISTRATION: ClinicalTrials.gov, identifier: NCT02036450.
KW - Aged
KW - Atrial Fibrillation/epidemiology
KW - Biomarkers/blood
KW - C-Reactive Protein/analysis
KW - Electrocardiography, Ambulatory
KW - Female
KW - Heart Rate
KW - Humans
KW - Inflammation Mediators/blood
KW - Inflammation/blood
KW - Male
KW - Middle Aged
KW - Risk Factors
KW - Time Factors
KW - C-reactive protein
KW - Implantable Loop Recorder
KW - Inflammation
KW - Atrial Fibrillation
U2 - 10.1093/europace/euag067
DO - 10.1093/europace/euag067
M3 - Article
C2 - 41964166
SN - 1099-5129
VL - 28
JO - Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology
JF - Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology
IS - 4
M1 - euag067
ER -