A meta-analysis of 92,816 people taking anticoagulants has shown that the risk of gastrointestinal (GI) bleeding related to the newer oral anticoagulants dabigatran and rivaroxaban is similar to that for warfarin.
But for patients older than 65, the risk of GI bleeding increases. By age 76, the risk may be 3 to 5 times higher when taking the newer anticoagulants compared to warfarin.
These findings were published in BMJ.
“The new anticoagulants have really been popular with patients who have previously only had one choice of oral anticoagulant,” said study author Neena S. Abraham, MD, of the Mayo Clinic in Scottsdale, Arizona.
“However, they may not be the right choice for everyone. Our findings definitely point toward important age-related risk that merit consideration when doctors are making treatment recommendations.”
Dr Abraham and her colleagues compared the risk of GI bleeding with newer anticoagulants and warfarin using national data available on privately insured patients and Medicare Advantage enrollees from the Optum Labs Data Warehouse.
Data on apixaban were not included in the study because there were too few patients prescribed apixaban in the dataset during the period of observation, from November 1, 2010, to September 30, 2013.
The cohort included 8578 (9.2%) patients on dabigatran, 16,253 (17.5%) on rivaroxaban, and 67,985 (73.2%) on warfarin. Patients were 18 years of age or older.
The researchers found that, among atrial fibrillation (AF) patients older than 75, the risk of GI bleeding was higher than with warfarin. The hazard ratios (HRs) were 2.49 (95% confidence interval [CI] 1.61 to 3.83) and 1.62 (95% CI 1.02 to 2.58), respectively.
However, among older patients without AF, the risk of GI bleeding was comparable with dabigatran and warfarin. The HRs were 1.56 (95% CI 0.42 to 5.80) and 2.73 (95% CI 0.83 to 8.94), respectively.
Older AF patients taking rivaroxaban had an increased risk of GI bleeding compared to patients taking warfarin. The HRs were 2.91 (95% CI 1.65 to 4.81) and 2.05 (95% CI 1.17 to 3.59), respectively.
And older patients without AF had an increased risk of GI bleeding with rivaroxaban compared to warfarin. The HRs were 4.58 (95% CI 2.40 to 8.72) and 4.40 (95% CI 2.43 to 7.96), respectively.
The researchers also found that, for those patients under 65, the newer agents seemed to confer a lower risk of GI bleeding than warfarin.
