Anticoagulation May Reduce Thromboembolic Risk in Liver Disease and Atrial Fibrillation

Oral anticoagulant (OAC) initiation in patients with liver disease, incident new atrial fibrillation or flutter (AF), and a high CHA₂DS₂-VASc-score are associated with a lower risk of thromboembolism, according to a study published in Clinics and Research in Hepatology and Gastroenterology.

Investigators compared the risk for thromboembolic events and bleeding related to initiation of OAC (vitamin K antagonists and direct OAC) in patients with liver disease, first diagnosed AF, and a CHA₂DS₂-VASc score of 1 or greater in men and 2 or greater in women.

The study used data from Danish nationwide administrative registries and included consecutive patients diagnosed from January 1, 2010, through December 31, 2017, and who were alive after 30 days.

The clinical endpoints were 5-year composite thromboembolic events, including ischemic stroke, transient ischemic attack, or venous thromboembolism; and 5-year composite bleeding events, which included gastrointestinal, intracerebral, or urogenital bleeding requiring hospitalization or epistaxis that required emergency department visit or hospital admission.

Follow-up began 30 days after the incident AF and continued until an event, emigration, death, a maximum follow-up of 5 years, or end of follow-up on December 31, 2018, whichever came first.

A total of 1238 patients were included. Of those patients, 409 initiated OAC, 28.0% of those with a CHA₂DS₂-VASc score of 1 to 2 (men) or 2 to 3 (women), and 25.8% of those with a CHA₂DS₂-VASc score of greater than 2 (men) or greater than 3 (women). The patients not treated with OAC (n=829) were aged median 69 (62-75) years, and 59.5% were men. The participants who were treated with OAC were aged median 71 (65-78) years, and 57.0% were men.

For patients with CHA₂DS₂-VASc scores of 1 to 2 (2-3 in women), the risk for thromboembolic events was low, regardless of OAC initiation (OAC, 6.5%; no OAC, 5.5%). The overall risks in patients with a CHA₂DS₂-VASc score of greater than 2 (>3 in women) were substantially increased, although they were significantly reduced in those taking any OAC (OAC, 15.6%; no OAC, 23.6%).

The standardized absolute risk for bleeding events was increased in patients with cirrhotic liver disease (OAC, 11.3%; no OAC, 15.8%) compared with noncirrhotic liver disease (OAC, 9.5%; no OAC, 7.4%) but were not significantly affected by OAC status.

The researchers noted that finite inferences about causality cannot be made owing to the observational nature of their study. Also, they were unable to investigate specific reasons why OAC was not prescribed, and patient characteristics such as risk scores were only assessed at baseline and may have changed over time. Furthermore, they were unable to incorporate data on labile international normalized ratio, and it was not possible to differentiate between mild and end-stage liver disease in the registries.

“OAC initiation in patients with liver disease and incident AF was associated with reduced [thromboembolic event] risk in men with a CHA₂DS₂-VASc score [greater than] 2 and in women with a CHA₂DS₂-VASc score [greater than] 3,” wrote the investigators. “Bleeding risk was not increased with OAC, irrespective of type of liver disease. Only a minority of AF patients with cirrhotic liver disease were treated with OAC, indicating a potential for reducing [thromboembolic events] burden in this population.”

Disclosure: Some of the study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.

Reference

Steensig K, Pareek M, Krarup AL, et al. Thromboembolism and bleeding in patients with atrial fibrillation and liver disease—a nationwide register-based cohort study: thromboembolism and bleeding in liver disease. Clin Res Hepatol Gastroenterol. Published online May 21, 2022. doi: 10.1016/j.clinre.2022.101952