Metrics from 2017 at the Fayetteville Veterans Affairs Heath Care Center (FVAHCC) Anticoagulation Clinic indicate that 43% of patients with atrial fibrillation (AF) who are prescribed warfarin have difficulty maintaining a therapeutic international normalized ratio (INR). These patients require frequent clinic appointments to adjust their regimens to ensure anticoagulation efficacy. FVAHCC policy requires a patient to return to the clinic for repeat INR evaluation within 5 to 14 days of the visit where INR was outside of the established therapeutic range.1 These frequent INR monitoring appointments increase patient and health care provider burden.
Direct oral anticoagulants (DOACs) are an alternative to warfarin for patients with AF who require anticoagulation. DOACs, which do not require regular efficacy monitoring, can be beneficial to patients who struggle to maintain a therapeutic INR when taking warfarin. FVAHCC policy regarding warfarin therapy monitoring allows for a maximum of 6 weeks between appointments. This period is often extended to 3 to 6 months for patients on DOACs.1
At FVAHCC, patients prescribed warfarin are managed in a centralized Anticoagulation Clinic led by a clinical pharmacy specialist (CPS). When a patient reports for an appointment, a clinical pharmacy technician performs point-of-care INR testing and asks standardized questions regarding therapy, including an assessment of adherence. The CPS then evaluates the patient’s INR test results, adjusts the dosage of warfarin as indicated, and determines appropriate follow-up.
A patient who is prescribed a DOAC is monitored by a CPS who works within a patient aligned care team (PACT). The PACT, a multidisciplinary team providing health care to veterans, includes physicians, nurses, pharmacists, dieticians, and mental health providers. Each CPS covers 3 or 4 PACTs. These pharmacists monitor all aspects of DOAC therapy at regular intervals, including renal and hepatic function, complete blood counts, medication adherence, and adverse effects.
Clinic and patient INR data are tracked using a time in therapeutic range (TTR) report generated by the US Department of Veterans Affairs (VA). The TTR report provides clinical information to enhance patient anticoagulation care.2 The TTR report identifies patients with an active order for warfarin and a diagnosis of AF or venous thromboembolism (VTE) whose INR is within therapeutic range (between 2 and 3) < 60% of the time over the previous 160 days.2 The patient must have had at least 3 INR levels drawn within that time frame for a TTR report calculation.2 The report excludes patients who were first prescribed warfarin within the previous 42 days and those with mechanical heart valves. The TTR report is used by the VA to see concrete facility-level results for quality improvement efforts.2
A quality improvement screening tool was developed to identify patients with AF being treated with warfarin who may appropriately transition to DOAC therapy. Anticoagulation Clinic patients were eligible for further evaluation if they had a TTR report level of < 60% and were prescribed indefinite warfarin therapy for AF.
The national VA goal is to have patient TTR report levels read > 60%. Therefore, the primary objective of this project was to improve Anticoagulation Clinic TTR metrics by targeting patients with TTR levels below the national goal.2
Patients who were successfully converted from warfarin to a DOAC were no longer included in Anticoagulation Clinic metrics and instead were followed by a PACT CPS. Thus, it was hypothesized that the average number of monthly Anticoagulation Clinic encounters would decrease on successful implementation of the screening tool. A secondary endpoint of the study evaluated the change in the total number of encounters of those who converted from warfarin to a DOAC.
Fewer clinic encounters could increase time available for the CPS to incorporate other initiatives into workflow and could increase clinic availability for newly referred veterans.