A new generation of oral anticoagulants ( nOAC ), which includes thrombin and factor Xa inhibitors, has been shown to be effective, but little is known about whether these drugs increase patients' risk for gastrointestinal bleeding. Patients who require oral anticoagulants therapy frequently have significant comorbidities and may also take Aspirin ( Acetylsalicylic acid ) and/or thienopyridines.
A systematic review and meta-analysis of the risk of gastrointestinal bleeding and clinically relevant bleeding in patients taking new oral anticoagulants was performed.
Researchers have analyzed data from 43 randomized controlled trials ( 151,578 patients ) that compared new oral anticoagulants ( regardless of indication ) with standard care for risk of bleeding ( 19 trials on gastrointestinal bleeding ).
The overall OR for gastrointestinal bleeding among patients taking nOAC was 1.45, but there was substantial heterogeneity among studies ( I2, 61% ).
Subgroup analyses showed that the OR for atrial fibrillation was 1.21, for thromboprophylaxis after orthopedic surgery the OR was 0.78, for treatment of venous thrombosis the OR was 1.59, and for acute coronary syndrome the OR was 5.21.
Among the drugs studied, the OR for Apixaban [ Eliquis ] was 1.23, the OR for Dabigatran [ Pradaxa ] was 1.58, the OR for Edoxaban [ Lixiana ] was 0.31, and the OR for Rivaroxaban [ Xarelto ] was 1.48.
The overall OR for clinically relevant bleeding in patients taking new oral anticoagulants was 1.16, with similar trends among subgroups.
In conclusion, studies on treatment of venous thrombosis or acute coronary syndrome have shown that patients treated with new oral anticoagulants have an increased risk of gastrointestinal bleeding, compared with those who receive standard care.
Better reporting of gastrointestinal bleeding events in future trials could allow stratification of patients for therapy with gastroprotective agents. ( Xagena )
Holster IL et al, Gastroenterology 2013;145:105-112