Long-Term Risk of Arrhythmias Increased in Patients with Inflammatory Bowel Disease

Previous studies have established that autoimmune inflammatory conditions, such as rheumatoid arthritis, psoriasis, and inflammatory bowel disease (IBD), raise the risk of cardiovascular disease (CVD), including ischemic heart disease, stroke, and thromboembolism. Some studies have investigated the association between IBD and cardiac arrhythmias, but results have been inconclusive.

Jiangwei Sun, Ph.D., a researchers at the Karolinski Institutet, led a study into the correlation between inflammatory bowel disease and cardiac arrhythmias.

To bring added clarity to the issue, first author Jiangwei Sun, Ph.D., from the Karolinska Institutet in Stockholm, and his colleagues conducted a cohort study exploring the long-term risk of arrythmias in patients with IBD. The results were published last month in PLOS Medicine.

Using the national Swedish database ESPRESSO (Epidemiology Strengthened by histoPathology Reports in Sweden), Sun and his colleagues identified patients with biopsy-confirmed IBD from 1969 to 2017. These included 24,954 patients with Crohn’s disease, 46,856 patients with ulcerative colitis and 12,067 patients with unclassified IBD. Each IBD patient was matched with up to five control reference individuals. Full siblings without IBS were also matched with their corresponding IBS siblings.

After a median follow-up of about 10 years, the researchers found that 7.6% of patients with Crohn's disease, 8.9% of those with ulcerative , and 8.2% of patients with unclassified IBDdeveloped overall arrhythmias versus 6.7%, 7.5%, and 6% of the respective reference individuals. The arrhythmias included atrial fibrillation or flutter, bradyarrhythmias, other supraventricular arrhythmias, and cardiac arrest and ventricular arrhythmias.

Compared with reference individuals, a significant increase in overall arrhythmias was observed in patients with Crohn's disease (54.6 versus 46.1 per 10,000 person-years), those with ulcerative colitis (64.7 versus 53.3 per 10,000 person-years), and patients with unclassifed IBD (78.1 versus 53.5 per 10,000 person-years). This translates to one extra case of arrhythmia per 80 people with Crohn's disease, 58 per people with ulcerative colitis and 29 wiht unclassified IBDcases during the same time period, an increased risk that persisted even 25 years after diagnosis.

The study also found that patients with IBD had an increased risk of developing each specific arrhythmia, except bradyarrhythmias. Similar results were observed in sibling comparison analyses.

According to the authors, chronic systemic inflammation is believed to play a significant role in the association between IBD and increased risk of arrhythmias. Inflammatory cytokines, including tumor necrosis factor (TNF), interleukin (IL)-1, and IL-6, directly affect cardiac electrical and structural changes. In addition, higher levels of the inflammatory biomarker C-reactive protein have been linked to an increased risk of developing or worsening atrial fibrillation.

The study authors emphasize the importance of raising awareness in clinicians of these long-term increased risks in patients with IBD. These findings could help guide the prescribing of IBD treatments and the implementation of treatment guidelines specific to this high-risk population.

“For those high-risk patients, a long-term follow-up and a risk assessment of modifiable and established CVD risk factors should be considered, since the influence of IBD on arrhythmias is expected to escalate with the increasing burden of CVD risk factors with age,” the authors wrote.

“Moreover, previous evidence has suggested that some medications (e.g., steroids) may lead to an increased risk of adverse CVD events, while others (e.g., anti-TNF agents or 5-aminosalicylic acid) may have a cardio-protective effect, the optimization of anti-inflammatory therapy while not triggering arrhythmias in those with additional established CVD risk factors should be carefully considered.”

“In addition, there are currently no specific guidelines for the assessment and management of CVD in patients with IBD and the robust findings of the present study underscore the urgency of developing relevant clinical guidelines,” Sun and colleageus added.