Impact of an oral anticoagulation self-monitoring and self-management program in patients with mechanical heart valve prosthesis

Objective: To analyze impact of implementation of an oral anticoagulation self-monitoring and self-management program among patients with mechanical valve prosthesis. Materials & methods: Observational and retrospective study performed in Hospital Moises Broggi, Barcelona, Spain. The program started on June 2019. The study compared 6-month period before and after the implementation of the program. Results: The study included 44 patients. There was a numerical increase of time in therapeutic range from 53.6 ± 21.3% to 57.1 ± 15.7% (p = 0.30). Proportion of patients with international normalized ratio (INR) >5 significantly decreased from 3.9 to 2.0% (p = 0.04). No significant differences were observed in thromboembolic or bleeding complications. Visits to emergency department decreased from (29.5 to 22.7%; p = 0.41). Conclusion: Oral anticoagulation self-monitoring and self-management program seems an appropriate approach that could provide additional benefits in selected patients with mechanical valve prosthesis.

Ischemic Stroke and Systemic Embolism in Warfarin Users With Atrial Fibrillation or Heart Valve Replacement Exposed to Dicloxacillin or Flucloxacillin

The antibiotics dicloxacillin and flucloxacillin induce cytochrome P450-dependent metabolism of warfarin. We explored the influence of these drug-drug interactions on the clinical effectiveness of warfarin therapy due to atrial fibrillation or heart valve replacement. Using the population-based Danish registers, we performed a propensity-score matched cohort study including around 50,000 episodes of dicloxacillin/flucloxacillin matched to phenoxymethylpenicillin and to no antibiotic, respectively. We estimated hazard ratios (HRs) with 95% confidence intervals (CIs) by comparing 21-day (days 7-28) risks of ischemic stroke/systemic embolism (SE) following initiation of each exposure. When compared with phenoxymethylpenicillin, dicloxacillin/flucloxacillin was associated with an HR of ischemic stroke/SE of 2.09 (95% CI 1.51-2.90; strongest for dicloxacillin (HR 2.17; 95% CI 1.56-3.02)). Use of an untreated comparator strengthened the association (HR 2.84; 95% CI 1.97-4.09). Dicloxacillin should be used with caution in patients receiving warfarin. This may also apply to flucloxacillin; however, more data on the risks associated with flucloxacillin exposure during warfarin therapy are needed.

Characteristics of software used in self-management of vitamin K antagonist therapy: A systematic review

INTRODUCTION AND GOAL

Currently, 1-2% of the population in developed countries are under treatment with oral anticoagulants. An appropriate strategy to deal with this increase in demand of treatment with oral anticoagulants and to manage the costs is the transfer of part or all of the responsibility for managing treatment to the patients. The use of information technology, particularly electronic health software, can be an appropriate method to improve the quality of self-management of treatment with these drugs. Therefore, this systematic review investigated studies that discuss the characteristics of electronic health software in self-management of oral anticoagulation therapy.

METHOD

A systematic review based on PRISMA protocol was conducted. In this study, articles were investigated that were in English. Articles existing in Cochrane, EMBASE and PubMed databases were searched up to 14 May 2017. Then, articles searched through Google Scholar were added to this study.

FINDINGS

The common characteristics used in most software included 'encryption in exchanging information', having an 'instruction module' and 'being Android-based'. In terms of functionality, 'communication between the patient and healthcare team' existed in most of the software.

CONCLUSION

The results of the study showed that the accuracy of administration of the dose of the drug using computer to reach a target international normalized ratio level was not less than those administered with experienced medical staff. In addition, the results indicated that important characteristics of the software include encryption in exchanging information, instruction module and Android-based instruction module. The most important characteristic was the interaction between the patient and the healthcare team.

Optimizing quality care for the oral vitamin K antagonists (VKAs)

Vitamin K antagonists (VKAs) have been the only oral anticoagulants for decades. The management of anticoagulant therapy with VKA is challenging because of the intricate pharmacological properties of these agents. The success of VKA therapy depends on the quality of treatment that is ensured through continuing comprehensive communication and education. The educational program should address important issues of the VKA therapy such as beginning of treatment, pharmacological, dietary, and drug-drug interactions, as well as treatment temporary suspension during surgical interventions or invasive maneuvers. In addition, the initial and continuing patient education is of imperative importance. A major role in the educational process may be addressed by patient associations. The quality of treatment is better reached if patients are followed in anticoagulation clinics. Moreover, a federation of anticoagulation clinics may improve patient care through regular meetings to update knowledge on VKA treatment. Learning objectives of this paper is to allow readers to correctly approach patients starting VKA treatment, recognize possible pitfalls of treatment, and provide adequate solutions.

Effectiveness and safety of self-managed oral anticoagulant therapy compared with direct oral anticoagulants in patients with atrial fibrillation

We compared the effectiveness and safety of direct oral anticoagulants (DOAC) vs patient self-managed warfarin therapy (PSM) in patients with atrial fibrillation. We linked prospectively registered data from university hospital clinics to nationwide Danish health registries. Primary effectiveness and safety outcomes were ischaemic stroke (incl. systemic embolism) and major bleeding. All-cause mortality and all-cause stroke were secondary outcomes. An inverse probability of treatment propensity-weighted approach was applied to adjust for potential confounding. The study cohorts included 534 patients treated with PSM and 2,671 patients treated with DOAC. Weighted rates of ischaemic stroke were 0.46 and 1.30 percent per year with PSM vs DOAC, hazard ratio (HR) 0.27 (95% confidence interval 0.11-0.68) with 2.5 years follow-up. Rates of major bleeding were 2.32 and 2.13 percent per year (HR 1.06 [0.69-1.63]). All-cause mortality was not statistically different (HR 0.67 [0.39-1.17]), whereas the incidence of all-cause stroke was significantly lower among patients treated with PSM with rates of 0.61 vs 1.45 percent per year (HR 0.36 [0.16-0.78]). In patients with atrial fibrillation, self-managed oral anticoagulant treatment was associated with a significantly lower risk of all-cause and ischaemic stroke compared to treatment with DOAC, whereas no significant differences were observed for major bleeding and mortality.

Predictors of anticoagulation quality in 15 834 patients performing patient self-management of oral anticoagulation with vitamin K antagonists in real-life practice: a survey of the International Self-Monitoring Association of Orally Anticoagulated Patients

Although patient self-management (PSM) of oral anticoagulation with vitamin K antagonists is recommended for patients requiring long-term anticoagulation, important aspects are still unclear. Using data from a large international survey (n = 15 834; median age 72 years; 30·1% female), we studied predictors of poor anticoagulation control (percentage of International Normalized Ratio values within therapeutic range below 75%) and developed a simple prediction model. The following variables were identified as risk factors for poor anticoagulation control and included in the final model: higher intensity of therapeutic range (odds ratio [OR] on every level 1·9; 95% confidence interval [CI] 1·8-2·0), long intervals between measurements (>14 d; 1·5; 95% CI 1·3-1·7), female sex (OR 1·3; 95% CI 1·2-1·4), and management other than PSM (OR 1·4; 95% CI 1·2-1·6). At a threshold of 0·2 (at least one variable present), the model predicted poor anticoagulation control with a sensitivity of 85·3% (95% CI: 84·0, 86·4) and a specificity of 28·5% (27·6, 29·5). The area under the receiver operated characteristic curve was 0·65. Using the proposed prediction model, physicians will be able to identify patients with a low chance of performing well, considering additional training, regular follow-up, or adjustment of therapeutic ranges.