This study compared treatment outcomes for patients receiving Rivaroxaban versus vitamin K antagonist (VKA) therapy for provoked deep venous thrombosis (DVT). It found that Rivaroxaban resulted in significantly fewer required clinic visits compared to VKA therapy. Additionally, the overall costs of treatment were comparable between the two groups when accounting for drug costs, clinic costs, and laboratory costs. However, less than two-thirds of patients on VKA therapy achieved a therapeutic international normalized ratio (INR) range over 60% of the time, indicating potential benefits of Rivaroxaban in maintaining therapeutic anticoagulation levels.

1. Emma Groarke1, William Courtney1, Jane Conway1, Elaine Conway1, Deborah Bourke1, Jean Saunders2, Michael Watts3 Denis O'Keeffe1
1. Department of Haematology, University Hospital Limerick, Dooradoyle, Limerick, 2. Department of Maths and Statistics,
University of Limerick, Limerick, 3. Department of Medicine, University Hospital Limerick, Dooradoyle, Limerick, Ireland
RIVAROXABAN VERSUS VITAMIN K ANTAGONIST IN PROVOKED DEEP VENOUS
THROMBOSIS – WHICH TREATMENT IS BETTER FOR THE PATIENT? A SINGLE
CENTER EXPERIENCE.
24 patients received rivaroxiban during the study
period. This data was matched to a comparable
historical group treated in our unit.
Mean age was 49.8 in VKA group versus 48 in
rivaroxaban group with 3:7 M/F ratio.
79% of DVTs were below knee. No significant bleeds
occurred in either group.
Patients on VKA had a mean time in theraputic range
>60% during their treatment in only 62.5% of cases.
VKA patients required many more clinic visits than
those on rivaroxaban. (14.58 visits versus 2.92).
We estimated cost to institution per patient for 3
months was €172.92 in the VKA group compared to
€32.87 for rivaroxaban including staff salaries,
laboratory costs, and materials. The cost on the Irish
Drugs Payment Scheme (DPS) is €8.07 for Warfarin at
5mg for 3 months, plus LMWH (€11.68 on DPS per
injection, estimated 7 needed) This produces an overall
cost of €260.68 for Warfarin compared to €273.30 for
rivaroxaban
A recent publication costing anticoagulation clinics in
Cork1 found an estimated cost of E48.50 per clinic visit
per patient.
Our figures did not take into account any personal
costs to the patient.
BACKGROUND
Deep venous thrombosis (DVT) is a common
medical condition that particularly occurs
associated with an underlying provoking factor.
Current guidelines recommend three months
of anticoagulant therapy for all patients with a
provoked DVT. Traditionally, the agent of
choice has been oral vitamin K antagonists
(VKA), in combination with subcutaneous low
molecular weight heparin. VKA require
intensive monitoring particularly during the
initiation of anticoagulation, and have a
relatively narrow therapeutic window. Direct
oral agents (DOACs) have recently been
licensed for the treatment of DVT.
OBJECTIVES
SUMMARY
Rivaroxaban treatment resulted in less hospital
clinic attendances, comparable overall costs
and potentially more therapeutic anticoagulation
with associated reduce risk to the patient.
This differential is particularly noticeable in
short term periods of anticoagulation
compounded by the need for multiple visits to
establish therapeutic INR’s and the need for the
addition of expensive injectable low molecular
weight heparin.RESULTS
CONCLUSIONS
REFERENCES
MATERIALS & METHODS
Prospective data was collected on new
patients with provoked DVT who received
Rivaroxaban for three months between
November 2013 and December 2014. This
data was compared to an age, sex, and type of
DVT matched group of historical patients who
received a VKA in our unit From January 2008
- November 2013.
Overall we collected data on 48 patients – 24
treated with Warfarin and 24 treated with
Rivaroxaban. We collected data on:
1. Age
2. Sex
3. Extent of DVT
4. Number of visits to the anticoagulation
clinic
5. Numbers of INRs performed
6. Time in theraputic range
7. Complications
1. Walsh C, et. al. Retrospective Costing of
Warfarin. Irish Medical Journal. 2014
May;107(5):133-5
2. Irish Drug Payments Scheme:
http://www.sspcrs.ie/druglist/search.jsp/pub
Dr. Emma Groarke, Haematology SpR
University Hospital Limerick
Dooradoyle, Limerick
emmagroarke@gmail.com
To compare the cost, safety, and patient clinic
visit requirements for Rivaroxaban versus
VKA.
MATERIALS & METHODS
We identified the resources involved in the provision of both warfarin and Rivaroxaban respectively. We calculated the
cost of providing the respective drugs. In the case of warfarin we also factored in the provision of seven days of
antithrombotic heparin at the commencement of the warfarin therapy.
We calculated the cost of running clinics and divided these costs into: labour, clinic maintenance, and sample analysis.
Further to this, we analysed blood test records of each of the warfarin patients on ‘ILAB’ blood test results electronic
database to assess the proportion of time that each patient spent with their International Normalised Ratio (INR) within
the clinically therapeutic range of 2-3.
VKA
(n=24)
Rivaroxaban
(n=24)
Age (mean) 49.8 years 48 years
Sex Males = 9
Females = 15
Males = 9
Females = 15
DVT type Limited = 19
Extensive = 5
Limited = 19
Extensive = 5
Visits to Clinic
(mean)
14.58 visits 2.92 visits
INRs performed
(mean)
14.58 INRs 2.93 INRs
Time in theraputic
range (total INRs
n=285)
Supratheraputic = 47
Theraputic = 186
Subtheraputic = 52
N/A
Complications
requiring cessation
None None
1. Our study showed that Rivaroxaban and
VKAs had a similar cost in the treatment of
provoked DVT for a 3 month period.
2. No difference in bleeding complications was
identified between the Rivaroxaban and
VKA group.
3. Less than two-thirds of patients on VKAs
spent had a mean time in theraputic range
>60%.
Per Unit VKA (per
patient/ 3 mos)
Rivaroxaba
n (per patient/ 3
mos)
STAFF COSTS
Nursing €125.58 €25.14
DRUG COSTS
Warfarin €2/ month €6.00
Rivaroxaban €240.43
Tinzaparin €11.68 €81.76 €0.00
MATERIAL
COSTS
INR Sample €2.16 €31.50 €6.30
Office supplies Letters: €0.60
Phlebotomy: €0.49
€8.75
€7.14 €1.43
TOTAL €260.73 €273.30
Table 2. Cost Breakdown
Table 1. Patient characteristics