Acceptibility of Patient Self-Testing of Oral Anticoagulation in New Patients.

Monitoring oral anticoagulation therapy (OAT) remains a significant burden on health care resources. Patient self-testing (PST) of OAT using point of care devices may alleviate these demands and improve the quality of treatment. Previous studies have shown limited benefit, as recruitment amongst patients previously established on OAT has proven to be difficult with only around 10–15 % of those invited agreeing to participate, suggesting that PST may only be suitable for a minority of patients. We aimed to assess whether PST is more acceptable to patients if offered at the commencement of treatment. 216 consecutive adults referred to anticoagulation clinics were assessed for their suitability for PST. Exclusion criteria included: short therapeutic duration (e.g. pre-cardioversion); known drug/alcohol abuse; atypical INR target values; language barriers; physical/intellectual impairment. Suitable patients were offered the opportunity to perform PST with 2 training sessions and thereafter monitor their INR every 1–2 weeks using CoaguChek S (Roche Diagnostics). It was noted during recruitment of the first 100 patients, that patients awaiting cardioversion accounted for a large proportion of the patients excluded (15/54, 28%), but many patients awaiting cardioversion received OAT in excess of six months. We therefore modified initial entry criteria, to include those with atrial fibrillation awaiting cardioversion. Of the 116 patients subsequently approached 37 (32%) were then recruited to PST (compared with only 17 cardiac patients from the first 100 enrolled into the study). 98 (45%) patients fulfilled our entry criteria for PST, of whom 54 (25%) consented to PST. Of the 118 ineligible patients: 23 had previously received OAT; 15 were awaiting cardioversion; the expected duration of OAT was less than 6 months in 13 patients; and PST was logistically impractical in 32 other patients. A further 35 were excluded for a wide variety of reasons including non-standard INR ranges, language barriers, discontinuation of OAT and planned surgical procedures. Only two of the 54 patients who started PST elected to return to hospital testing. Overall 53 % (52/98) of eligible patients have continued to self-test. The INR values obtained from these patients showed that their oral anticoagulant control remained stable (mean time in therapeutic range of 71%), and compared favourably to those patients electing to attend our routine anticoagulant clinic. Our data show that patients offered PST as an alternative to routine clinic management during induction of anticoagulation were more likely to participate in PST than established patients. Furthermore, the vast majority of patients (96%) continued to self-test, a higher figure than previous studies involving established patients.