Point-of-Care INR Testing

50th Annual Dalhousie Pharmacy Refresher November 2014 Janice Mann MD Knowledge Mobilization

Disclosure:

• I am an employee of CADTH

• I am a physician (not currently practicing)

• I HTA

CADTH is a health technology assessment

agency

We inform technology-related decision-making

in health care

Health Technology Assessment

• Systematic evaluation of the evidence on the properties, effects, and/or impacts of health care technology (drugs, devices, procedures)

The Role of HTA

Reliable and timely provision of (synthesized, appraised) evidence:

• Is it safe? • For whom does it work and when? • Is it better than what we already have/do? • Does it provide value for money? • Can we afford it? Can we afford not to? • What’s the trade-off? • What else needs to be considered?

Why use HTA Evidence in Clinical Practice? • Rigorous • Balanced • Relevant • Synthesis of large volume of research • Freely available • Positive experience of clinicians who have used HTA in

practice

“You changed my practice”

CADTH’s POC INR Optimal Use Project

Objective:

• To support well-informed decisions about the acquisition and/or optimal implementation of POC INR technology

• To inform decision makers regarding the accuracy, as well as the clinical and cost-effectiveness of POC INR compared with standard laboratory testing, and compared with other POC INR devices.

Background

• Approximately 350,000 Canadians are taking oral anticoagulation therapy (OAT) – mostly warfarin

• Patients must be monitored for over-anticoagulation (possibly resulting in bleeding or hemorrhage) and under-anticoagulation (which could result in blood clots), by measuring International Normalized Ratio (INR)

• INR monitoring typically occurs every 3-5 weeks in patients stabilized on anticoagulant therapy, however more frequent monitoring is required when starting therapy.

INR Testing

• The gold standard for monitoring INR is lab testing of blood obtained by venipuncture, in hospital or at an anticoagulation clinic.

• Point of care (POC) testing is another way to monitor INR.

• POC testing is testing at or near where a patient is located.

POC INR Testing

The aims of POC testing are: • Convenience for the patient • Faster test results to the health care provider • Faster clinical decision-making • Improved clinical outcomes and reduced health care

resource use

POC INR Testing

• The POC INR device is called a coagulometer. • There are 9 POC coagulometers currently or soon to be

available in Canada • POC testing for INR involves putting a sample of whole

blood, usually capillary blood from a finger stick, onto a test strip.

• POC devices and test strips are not currently an insured benefit in most Canadian jurisdictions, although they may be available as part of hospital or clinic supply budgets.

POC INR Devices in Canada Point of Care INR Devices Available, or Soon to be Available, in Canada

Manufacturer Product

Roche CoaguChek XS*

Roche CoaguChek XS Plus*

Roche CoaguChek XS Pro*

International Technidyne Corporation ProTime*

Hemosense Inc INRatio*

Helena Laboratories Cascade

Abbott Laboratories CoaguSense

Abbott Laboratories i-STAT*

Universal Biosensors Mobius (not yet officially named)

iLine Microsystems iLine device

*devices approved for use in Canada

Options for Implementing POC INR

Patient self-management (PSM) • Patient self-tests the INR using a POC device, and self-

adjusts the dose of the anticoagulant medication based on the results using a predetermined algorithm or protocol

Patient self-testing (PST) • Patient self-tests the INR using a POC device and a

clinician adjusts the dose of anticoagulant medication based on the results

Clinic-based POC INR testing • POC testing is performed in a clinical setting such as a

physician’s office or anticoagulation clinic.

Questions about POC INR vs. Lab

1. Is POC INR testing as effective as laboratory testing for determining whether INR is within the therapeutic range?

2. In what healthcare settings are there clinical and cost advantages or disadvantages for the use of POC INR testing over laboratory testing?

3. In what healthcare settings are there advantages other than clinical and cost (for example, access to testing or convenience) for POC INR testing over laboratory testing?

4. Is there one particular POC device that is superior to others in terms of clinical, cost, and other advantages?

POC INR vs. Lab Testing

What’s the Evidence Say?

POC INR — Clinical Review

• The clinical review included 48 articles reporting on 47 unique studies, including five RCTs assessing the impact of POC INR testing on clinical outcomes.

• Only studies evaluating POC coagulometers approved and available for purchase in Canada were eligible for inclusion

Summary of Evidence — Clinical

Precision and Accuracy: • For INR values within the typical target therapeutic range (2

to 3.5), POC meters produced results comparable to lab

• Mean difference in INR values between POC INR and lab was within 0.5 units the majority of the time, with a maximum average difference of 0.8.

• Strong correlation between POC INR and lab

• However, the difference between INR values between the two methods may increase at high INR values ≥ 3.5 units.

Summary of Evidence — Clinical

Time within Therapeutic Range (TTR): • POC coagulometers led to an average increase of 6.14% in

TTR compared with lab testing, equivalent to approximately 25 days over the course of one year.

Clinical Outcomes (Adverse Events): • POC meters included in this review did not lead to a

statistically significant change in the rate of major bleeding or thromboembolic events or strokes compared with lab.

Summary of Evidence — Clinical

Patient Satisfaction and Quality of Life: • Limited data on patient satisfaction reported preference for

POC over lab testing. Comparison of POC INR devices: • Evidence was identified comparing Coaguchek XS,

Coaguchek XS Plus, INRatio, i-STAT, or ProTime to laboratory testing.

POC INR — Economic Analysis • A cost-effectiveness analysis comparing laboratory testing,

patient self-management, patient-self testing, and POC INR testing in a clinic setting in terms of incremental cost per quality-adjusted life-years (QALY) gained.

• An expanded payer perspective that included patient level costs associated with lab or clinic visits was also conducted to reflect scenarios in which patient travel costs are reimbursed by public payers.

Summary of Evidence — Economic

• Using retail prices for POC devices ($499 per patient-grade POC and $2,056 for professional-grade POC), and $8.33 per test strip, lab testing was the least costly option with a total cost of $7,033 per patient.

• Patient self-management (PSM) emerged as a cost-effective option ($13,028 per QALY gained compared to lab)

• Patient self-testing (PST) and clinic-based POC were more

costly and less effective.

Summary of Evidence — Economic

• When considering patient travel costs for clinic and lab

visits, PSM was the least costly option.

• These results remained robust to variations in estimates of device costs, frequency of testing, health care provider costs in various settings, and patient travel time (such as rural versus urban settings).

POC INR — Bottom Line

• POC INR testing with any currently available POC INR device is an accurate alternative to lab INR testing.

• Patient self-management (POC INR testing + dose adjustment) is the most cost-effective option, when feasible.

• Patient self-testing with health care provider dose adjustment may be an option when lab INR testing is difficult.

• Clinic-based POC INR testing requires careful consideration of context and costs.

Implementing POC INR Testing • Offer patients, if they are willing and able, the option to test

their own INRs and make dose adjustments to their medication. Provide them with education and support.

• If patients are not willing or able to manage their own dose adjustments, self-testing of INR with dose adjustments by a health professional may be an option, but only if there are significant barriers to patients having their INR regularly tested in a lab.

• POC INR testing in a clinic can be more costly than lab testing; however, consider the context of your practice site before implementing.

http://hospitalnews.com/point-care-inr-testing/

For More Information

Janice Mann (Ottawa) janicem@cadth.ca

Lisa Farrell (NS) lisaf@cadth.ca

Visit: www.cadth.ca and www.cadth.ca/clots

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