Influence of stroke and bleeding risk on prescribing of oral anticoagulants in older inpatients; has the availability of direct oral anticoagulants changed prescribing?

Background: Little is known about changes in prescribing practices in Australia since the introduction of the direct oral anticoagulants (DOACs). Our objective was to examine if the availability of DOACs has coincided with a change in prescribing of oral anticoagulants in older hospital inpatients with regard to risk factors for stroke and bleeding.

Methods: A prospective observational study was conducted between October 2012 and August 2015 of inpatients aged over 60 years initiated on an oral anticoagulant in a large metropolitan, tertiary referral, public teaching hospital in Australia. Treatment groups were patients who commenced an oral anticoagulant prior to inclusion of DOACs on the formulary and those who commenced after the introduction of DOACs. Subgroup analyses were conducted in patients with atrial fibrillation (AF). Differences in clinical characteristics and risk for stroke and bleeding were calculated using the CHADS₂ and HAS-BLED scores, respectively, were examined.

Results: A total of 289 patients were included. Inpatients prescribed an oral anticoagulant after the introduction of DOACs were significantly older, a greater proportion were female and more likely to have had a prior stroke. This was associated with a statistically higher CHADS₂ score in the post-DOAC group. Similar findings were observed when limiting the sample to patients with AF. Patients with AF who were at greatest likelihood of having a bleeding event were less likely to be treated with a DOAC.

Conclusion: Since the introduction of the DOACs, patients who may have previously received no therapy or suboptimal treatment were now more likely to be receiving anticoagulation, suggesting an appropriate change in prescribing practice.