Impact of Pharmacists’ audit on improving the quality of prescription of dabigatran etexilate methanesulfonate: a retrospective study

BACKGROUND Appropriate prescription of dabigatran etexilate methanesulfonate (JAN) is more complicated than assumed, because there are totally 10 items of contraindications and instructions for dosage reduction depending on patients' characteristics. We aimed to study whether the routine audit of first-time prescriptions of dabigatran performed by pharmacists is effective in improving the quality of prescription. METHODS A retrospective re-audit was performed on all the prescriptions of dabigatran issued at Kitahara International Hospital, Tokyo between March 2011 and February 2014, by evaluating the prescriptions rigorously against the approved prescribing information of the drug. The original routine audit of the prescriptions for inpatients was performed by hospital pharmacists using electronic medical records (EMR), whereas the audit for ambulant patients receiving external prescriptions was performed by community pharmacists using information obtained mainly by questioning patients. The frequencies of inappropriate prescriptions detected by the re-audit in the two groups were compared. RESULTS Two hundred and twenty-eight patients (131 ambulant patients and 97 inpatients) were prescribed dabigatran for the first time during the study period. All patients met the approved indications. While 33% of the prescriptions for ambulant patients showed at least one violation of the approved usage, only 11% of the prescriptions for inpatients showed violations (p < 0.001). Two ambulant patients with creatinine clearance < 30 mL/min were dispensed dabigatran, whereas no such case was found among inpatients. A significantly greater proportion of ambulant patients aged ≥70 years showed violation of the instruction for dosage reduction compared to inpatients of the same age group (18 and 4%, respectively). CONCLUSION The present study suggests that pharmacists may achieve better performance in auditing prescriptions of dabigatran when medical records are fully available than when information is available mainly by questioning patients. Further large-scale studies are required to clarify whether the audit of dabigatran prescriptions improves ultimate therapeutic outcomes or complications.