This study aimed to evaluate the clinical effectiveness of patient self management compared with a routine primary care clinic. Patient self management involved near patient testing technology (Coaguchek), which has been shown to be safe in previous studies.14,17,19,26
Patients managed the near patient testing device with minimal support following the training, and coped with both IQC and EQA procedures.
No difference in INR control or serious adverse events was found between the two groups, demonstrating that selected UK patients are capable of measuring their own INR and dosing their warfarin accordingly. These are important data because a criticism of previous studies is that the standard care comparitor was suboptimal,26–28
whereas INR percentage time in range data for routine care are demonstrably better in our study than previously reported data (77% versus 50%, respectively).14,29
Only 38% of patients receiving warfarin were considered suitable for patient self management and nearly one third (28%) of these refused to participate. Furthermore, because about a quarter of those patients randomised to patient self management withdrew from the study overall, just under half of those considered eligible for patient self management consented and completed the study. Therefore, these excellent INR results may reflect that only motivated, compliant, and long term treatment patients were recruited.
Although poor treatment adherence has been cited as a major cause of unstable anticoagulation with warfarin,30
patient self management has been shown to have a positive influence in the control of diabetes,31,32
Therefore, it is possible that instead of aiming patient self management primarily at motivated patients, a package of training, self management, and support may be the solution to encourage motivation in less dedicated patients. The results of our study interviews agreed with previous ones in that poor adherence can be improved with patient self management. For most patients, the reduction in professional support was seen as a positive aspect of their care, as long as support was available. Further studies are needed to elucidate definitions for selection, perhaps based more on patient self selection and the identification of inappropriate patients after training and assessment.
Training was based on the German nationally approved programme for anticoagulation29
and other centres have described similar training of varying intensity.20
The patient self management group in our study performed INR tests almost three times more frequently than the routinely managed group in demonstrating equivalent therapeutic control. The two weekly testing conducted within our study was based on previous studies.29
At present, there are no formal guidelines relating to the frequency of testing for optimum management and it is an area that also requires further investigation.
“For most patients, the reduction in professional support was seen as a positive aspect of their care, as long as support was available”
The high cost for patients in the intervention arm is a function of the number of tests undertaken and the consumable and equipment costs of self management tests. If this technology becomes more more widely available and its associated costs fall over time then the costs for patient self management could become more favourable. Test strips are now available on prescription, which would enable more patients to undertake patient self management, although there are obvious cost implications for the National Health Service. However, on current evidence, a more conventional approach to the management of patients receiving anticoagulation is by far the cheapest option.
For our study, patients successfully performed EQA on four separate occasions and these results will contribute to the debate concerning patients’ ability to manage EQA.34
IQC is considered by some to be an adequate performance test for the reliability of the result, but although it is a useful test to assess day to day precision it could be argued that the target range is unacceptably wide. In addition, if EQA is deemed essential for hospital and primary care clinics undertaking INR measurement, the same conditions must apply to patient self management, although this has not been referred to in previous patient self management studies.
In conclusion, patient self management is in an embryonic phase in the UK, and these are the first data to suggest that it is as clinically effective as routine care, in this case primary care management of oral anticoagulation. Evidently patient self management is more costly than practice based management as a result of increased use of the near patient testing device, test strips, quality assurance, and training. Some of these excess costs may not prove necessary. Nevertheless, if patient self management costs are confirmed as higher than routine care they could only be recouped within the National Health Service by reductions in serious adverse events, particularly stroke. Given that routine care in the UK is already good this outcome is unlikely.
Before consideration can be given to widespread adoption of this model further UK research is needed. This will need to deal with issues around the nature of training, the definition of patient eligibility, the frequency of testing, and costs. Although cost effectiveness appears unlikely considering these preliminary data, patient self management has been shown to be safe and effective for the minority of patients who might select it.
Take home messages
- There were no significant differences in the international normalised ratio control between the self management patients and the control group and there were no serious adverse events in the self management group
- Thus, patient self management was as safe as primary care management for this selected population
- However, the costs were significantly higher in the self managemnt group (£90 v £425/patient/year)
- Further studies are needed to elucidate whether this model of care is suitable for a larger population