Having autoimmune diseases (AIDs) seems to increase the risk of developing atrial fibrillation according to the findings of a prospective study by Dutch researchers.
Atrial fibrillation (AF) is the most common cardiac arrhythmia and data from 2017 suggests that globally, there were 3.046 million new cases. Although the underlying cause of AF remains uncertain, there is a suggestion of a mechanistic link with inflammatory processes. Moreover, a feature of autoimmune diseases such as rheumatoid arthritis is inflammation and one meta-analysis found a 29% higher risk of AF among those with rheumatoid arthritis. Nevertheless, the link between AF and other autoimmune disorders is less clear. As a result, in the current study, the Dutch team turned to data held in the UK Biobank and looked for those diagnosed rheumatic fever, gastrointestinal AIDs and other AIDs e.g. those affecting the musculoskeletal, connective tissues and neurological systems. Such individuals were monitored over time for the development of AF. In addition, the team collected data on cardiovascular risk factors such as hypertension, type 2 diabetes, body mass index etc and which were adjusted for in regression models.
Autoimmune diseases and development of atrial fibrillation
A total of 494,072 individuals with a median age of 58 (54.8% female) were followed for a median of 12.8 years and during this time 5.5% of the cohort developed AF.
In fully adjusted models, among those with rheumatic fever but no cardiac involvement, there was a 47% higher risk of developing AF (hazard ratio, HR = 1.47, 95% CI 1.26 – 1.72). Similarly, there were elevated risks for those with several autoimmune diseases including Crohn’s disease (HR = 1.23), ulcerative colitis (HR = 1.17), rheumatoid arthritis (HR = 1.39) systemic lupus erythematosus (HR = 1.82) and systemic sclerosis (HR = 2.32).
When analysed by gender, the researchers found that for many of these disorders, there was a higher risk among women although the risk was higher among men but only for ulcerative colitis.
The authors concluded that whilst their data showed how autoimmune diseases were associated with the development of AF, further evidence was need to support the clinical translation of these findings.
Tilly MJ et al. Autoimmune diseases and new-onset atrial fibrillation: a UK Biobank study. Eurospace 2022 (Online ahead of print)