# Association between systemic inflammation and risk of atrial fibrillation in cancer survivors: a population-based cohort study using UK biobank

## TL;DR

Cancer survivors with higher inflammation levels may be at greater risk of developing atrial fibrillation, especially if they haven't had radiotherapy.

## Contribution

This study identifies a potential link between systemic inflammation and atrial fibrillation in cancer survivors using population-based data.

## Key findings

- Elevated C-reactive protein levels are associated with increased atrial fibrillation risk in cancer survivors.
- The association weakens after adjusting for lifestyle factors but remains suggestive.
- The link is stronger in cancer survivors not receiving radiotherapy.

## Abstract

Cancer survivors (CSs) are at increased risk of atrial fibrillation (AF), potentially due to cancer-related inflammation and treatment effects. While inflammation has been implicated in both cancer and AF, the association between C-reactive protein (CRP) and AF risk in CSs remains unclear.

We analyzed data from 19,677 UK Biobank participants (mean age 60; 34.2% male) with a prior cancer diagnosis. Incident AF was evaluated using competing-risk Cox proportional hazards models, adjusting for sociodemographic, lifestyle, and clinical factors.

Over a median follow-up of 10.4 years, 836 CSs (4.2%) developed AF.

Competing risk analysis revealed that the significant association between elevated CRP (> 2 mg/L) and AF risk in CSs, observed in models adjusted for sociodemographic and clinical factors (HR 1.21, 95% CI 1.06–1.37; P = 0.005), progressively attenuated with further adjustment for lifestyle factors (HR 1.14, 95% CI 0.99–1.31; P = 0.076). Despite losing statistical significance in the fully adjusted model, a consistent, suggestive trend was observed. This association was particularly pronounced in individuals not receiving radiotherapy.

Our findings suggest that systemic inflammation is associated with an increased risk of AF among CSs, particularly in individuals without a history of radiotherapy. Further studies are needed to explore underlying mechanisms and therapeutic implications.

The online version contains supplementary material available at 10.1186/s40959-025-00414-6.