Direct oral anticoagulants uptake and an oral anticoagulation paradox

Patients' and clinicians' perceptions of oral anticoagulants in atrial fibrillation: a systematic narrative review and meta-analysis

Background

Atrial fibrillation (AF) increases the risk of developing a stroke by 20%. AF related strokes are associated with greater morbidity. Historically, warfarin was the anticoagulant of choice for stroke prevention in patients with AF but lately patients are being switched or started on direct oral anticoagulants (DOACs). DOACs are promoted as safer alternatives to warfarin and it is expected that they will be associated with fewer challenges both for patients and healthcare professionals. This systematic narrative review aimed to explore perspectives of patients and professionals on medicines optimisation of oral anticoagulation with vitamin K antagonists and DOACs in atrial fibrillation.

Methods

Prospero registration CRD42018091591. Systematic searches undertaken of research studies (qualitative and quantitative), published February 2018 to November 2020 from several databases (Web of Science, Scopus, Medline Via Ovid, CINHAL via Ebsco, and PubMED via NCBI) following PRISMA methodology. Data were organised using Covidence software. Two reviewers independently assessed the quality of the included studies and synthesized the findings (thematic analysis approach).

Results

Thirty-four studies were included. Studies were critically appraised using established critical appraisal tools (Qualsyst) and a risk of bias was assigned. Clinicians considered old age and the associated complexities such as co-morbidities and the increased potential for bleeding as potential barriers to optimising anticoagulation. Whereas patients’ health and medication beliefs influenced adherence. Notably, structured patient support was important in enhancing safety and effective anticoagulation. For both patients and clinicians, confidence and experience of safe anticoagulation was influenced by the presence of co-morbidities,  poor knowledge and understanding of AF and the purpose of anticoagulation.

Conclusion

Age, complex multimorbidity and polypharmacy influence prescribing, with DOACs being perceived to be safer than warfarin. This systematic narrative review suggests that interventions are needed to support patient self-management. There are residual anxieties associated with long term anticoagulation in the context of complexities.

Trial registration

Not applicable.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12875-021-01590-x.

Barriers and facilitators to the uptake of new medicines into clinical practice: a systematic review

BACKGROUND

Implementation and uptake of novel and cost-effective medicines can improve patient health outcomes and healthcare efficiency. However, the uptake of new medicines into practice faces a wide range of obstacles. Earlier reviews provided insights into determinants for new medicine uptake (such as medicine, prescriber, patient, organization, and external environment factors). However, the methodological approaches used had limitations (e.g., single author, narrative review, narrow search, no quality assessment of reviewed evidence). This systematic review aims to identify barriers and facilitators affecting the uptake of new medicines into clinical practice and identify areas for future research.

METHOD

A systematic search of literature was undertaken within seven databases: Medline, EMBASE, Web of Science, CINAHL, Cochrane Library, SCOPUS, and PsychINFO. Included in the review were qualitative, quantitative, and mixed-methods studies focused on adult participants (18 years and older) requiring or taking new medicine(s) for any condition, in the context of healthcare organizations and which identified factors affecting the uptake of new medicines. The methodological quality was assessed using QATSDD tool. A narrative synthesis of reported factors was conducted using framework analysis and a conceptual framework was utilised to group them.

RESULTS

A total of 66 studies were included. Most studies (n = 62) were quantitative and used secondary data (n = 46) from various databases, e.g., insurance databases. The identified factors had a varied impact on the uptake of the different studied new medicines. Differently from earlier reviews, patient factors (patient education, engagement with treatment, therapy preferences), cost of new medicine, reimbursement and formulary conditions, and guidelines were suggested to influence the uptake. Also, the review highlighted that health economics, wider organizational factors, and underlying behaviours of adopters were not or under explored.

CONCLUSION

This systematic review has identified a broad range of factors affecting the uptake of new medicines within healthcare organizations, which were grouped into patient, prescriber, medicine, organizational, and external environment factors. This systematic review also identifies additional factors affecting new medicine use not reported in earlier reviews, which included patient influence and education level, cost of new medicines, formulary and reimbursement restrictions, and guidelines.

REGISTRATION

PROSPERO database (CRD42018108536).

Barriers and facilitators for optimizing oral anticoagulant management: Perspectives of patients, caregivers, and providers

BACKGROUND

Oral anticoagulants (OACs) are very commonly prescribed for prevention of serious vascular events, but are also associated with serious medication-related bleeding. Mitigation of harm is believed to require high-quality OAC management. This study aimed to identify barriers and facilitators for optimal OAC management from the perspective of patients, caregivers and healthcare providers.

METHODS

Using a qualitative descriptive study design, we conducted five focus groups, three with patients and caregivers and two with health care providers, in two health regions in Southwestern Ontario. An expert facilitator led the discussions using a semi-structured interview guide. Each session was digitally recorded, transcribed verbatim and anonymized. Transcripts were analyzed in duplicate using conventional content analysis.

RESULTS

Forty-two (19 patients, 7 caregivers, and 16 providers including physicians, nurses and pharmacists) participated. More than half of the patients received OAC for the treatment of venous thromboembolism (57.9%) and the majority (94.7%) were on chronic therapy (defined as >3 years). Data analysis organized codes describing barriers and facilitators into 4 main themes-medication-related, patient-related, provider-related, and system-related. Barriers highlighted were problems with medication access due to cost, patient difficulties with adherence, knowledge and adjusting their lifestyles to OAC therapy, provider expertise, time for adequate communication amongst providers and their patients, and health care system inadequacies in supporting communications and monitoring. Facilitators identified generally addressed these barriers.

CONCLUSIONS

Many barriers to optimal OAC management exist even in the era of DOACs, many of which are amenable to facilitators of improved care coordination, patient education, and adherence monitoring.

The association between increasing oral anticoagulant prescribing and atrial fibrillation related stroke in Ireland

AIMS

Recent increases in the number of patients with atrial fibrillation (AF) prescribed oral anticoagulants (OAC) are evident in Ireland and internationally, largely due to the availability of direct oral anticoagulants (DOACs). This study aimed to determine the rate of stroke in the context of increasing anticoagulation utilisation, with a focus on AF-related ischaemic stroke (IS).

METHODS

Dispensing data for OACs were identified for the period 2010-2018 as well as hospital discharges for IS (2005-2018). Irish National Stroke Register data were used to elucidate the characteristics of patients with acute ischaemic stroke.

RESULTS

The number of patients prescribed OACs increased by 94% from 2010-2018 with a significant change from 2013 (β = 2.57, P = .038), associated with a large increase in the number of patients on DOACs. There was 3.3-fold increase in expenditure on OACs nationally from 2013 to 2018, of which 94% was DOAC related. Using the 2013 timepoint, ischaemic stroke rates until 2018 did not show a significant deviation from the previous trend (β = 0.00, P = .898). The percentage of AF-related ischaemic stroke was stable from 2013 to 2017 with a 4.5% decrease in 2018. The percentage of ischaemic stroke patients with previously diagnosed AF decreased from 2013 to 2018; however, there was an increase in the percentage of ischaemic strokes while on OAC in this cohort.

CONCLUSION

Large increases in OAC utilisation have not resulted in changes in ischaemic stroke rates at a national level. The percentage of ischaemic strokes with a previous diagnosis of AF has decreased indicating a possible benefit from greater OAC utilisation. However, the percentage presenting with an ischaemic stroke while on OAC treatment is increasing. The increase in patients presenting with stroke while treated with OAC may largely reflect the national increase in patients prescribed DOACs but the findings raise concerns about treatment failures. The real-world effectiveness of DOACs requires further examination.

Update on drug interactions with non-vitamin-K-antagonist oral anticoagulants for stroke prevention in elderly patients

Introduction: We update the knowledge, since the last review in 2017, about drug-drug interactions (DDI) of non-vitamin-K-antagonist oral anticoagulants (NOAC) in patients ≥75 years.Areas covered: The literature was searched for: 'dabigatran,' 'rivaroxaban,' 'edoxaban,' or 'apixaban' and drugs, affecting platelet function, CYP3A4-, CYP2C9-, or P-Gp-activity. Pharmacodynamic DDI of NOAC with drugs affecting platelet function like nonsteroidal anti-inflammatory drugs and antiplatelet agents occur most frequently. Pharmacokinetic DDI with NOAC were found for 37 of 117 drugs. Reports about DDI with NOAC were found for 51% of P-gp-affecting, 38% for CYP2C9-affecting and 27% for CYP3A4-affecting drugs. Reports about DDI of cardiovascular drugs with NOAC were the most prevalent, followed by anti-infective and nervous system drugs. NOAC plasma levels were measured in retrospective and cohort studies and were associated with concomitant medication. Reports about DDI of NOAC were found in 71 patients ≥75 years.Expert opinion: The knowledge about DDI of NOAC in elderly patients is very limited. Studies should be carried out to investigate the role of drugs potentially interacting with NOAC, which until now have not been investigated. When studying DDI of NOAC, care should be taken to include elderly patients with impaired renal function and patients on polymedication.

Prior Anticoagulation in Patients with Ischemic Stroke and Atrial Fibrillation

OBJECTIVE

The aim was to evaluate, in patients with atrial fibrillation (AF) and acute ischemic stroke, the association of prior anticoagulation with vitamin K antagonists (VKAs) or direct oral anticoagulants (DOACs) with stroke severity, utilization of intravenous thrombolysis (IVT), safety of IVT, and 3-month outcomes.

METHODS

This was a cohort study of consecutive patients (2014-2019) on anticoagulation versus those without (controls) with regard to stroke severity, rates of IVT/mechanical thrombectomy, symptomatic intracranial hemorrhage (sICH), and favorable outcome (modified Rankin Scale score 0-2) at 3 months.

RESULTS

Of 8,179 patients (mean [SD] age, 79.8 [9.6] years; 49% women), 1,486 (18%) were on VKA treatment, 1,634 (20%) on DOAC treatment at stroke onset, and 5,059 controls. Stroke severity was lower in patients on DOACs (median National Institutes of Health Stroke Scale 4, [interquartile range 2-11]) compared with VKA (6, [2-14]) and controls (7, [3-15], p < 0.001; quantile regression: β -2.1, 95% confidence interval [CI] -2.6 to -1.7). The IVT rate in potentially eligible patients was significantly lower in patients on VKA (156 of 247 [63%]; adjusted odds ratio [aOR] 0.67; 95% CI 0.50-0.90) and particularly in patients on DOACs (69 of 464 [15%]; aOR 0.06; 95% CI 0.05-0.08) compared with controls (1,544 of 2,504 [74%]). sICH after IVT occurred in 3.6% (2.6-4.7%) of controls, 9 of 195 (4.6%; 1.9-9.2%; aOR 0.93; 95% CI 0.46-1.90) patients on VKA and 2 of 65 (3.1%; 0.4-10.8%, aOR 0.56; 95% CI 0.28-1.12) of those on DOACs. After adjustments for prognostic confounders, DOAC pretreatment was associated with a favorable 3-month outcome (aOR 1.24; 1.01-1.51).

INTERPRETATION

Prior DOAC therapy in patients with AF was associated with decreased admission stroke severity at onset and a remarkably low rate of IVT. Overall, patients on DOAC might have better functional outcome at 3 months. Further research is needed to overcome potential restrictions for IVT in patients taking DOACs. ANN NEUROL 2021;89:42-53.

Oral Anticoagulants Preference in Hospitalized Patients with Acute Deep Vein Thrombosis or Non-Valvular Atrial Fibrillation

(1) Aim: The aim of this study was to assess the preferences of oral anticoagulants (OA) in patients diagnosed with deep vein thrombosis (DVT) of lower limbs or non-valvular atrial fibrillation (AF) requiring anticoagulation for medium/long term. (2) Materials and methods: the study included consecutive patients admitted with a diagnosis of either acute DVT of lower limbs (without signs of pulmonary embolism) or non-valvular AF who required oral anticoagulation, in a time frame of 18 months from January 2017 until June 2018. The following data were recorded: demographic variables, comorbidities (ischemic heart disease, arterial hypertension, heart failure, stroke, peripheral artery disease, diabetes mellitus, obesity), type and dose of OA (acenocoumarol, dabigatran, apixaban, rivaroxaban), complications due to the use of OA. (3) Results: AF patients were older and had considerably more cardiovascular comorbidities than DVT patients. Vitamin K antagonists (VKA) were more likely to be administered in patients with AF, as they had indication for indefinite anticoagulation. VKA were more frequently prescribed in patients with ischemic heart disease, heart failure, and diabetes compared with DVT patients. Moreover, complications related to OA use were more frequent in the VKA group. Almost half of patients with acute DVT (48.5%) were treated with direct OA (DOAC) rather than VKA, and only a quarter of AF patients (24.8%) were treated with DOACs.

Direct oral anticoagulants uptake and an oral anticoagulation paradox

Oral anticoagulation (OAC) for stroke prevention in patients with atrial fibrillation is underutilised. One of the impediments to warfarin therapy is the frequent monitoring required, usually at a specialised warfarin clinic. The advent of direct oral anticoagulants (DOACs) facilitates OAC therapy without an onerous monitoring regimen. This benefit may result in the more significant adoption of DOACs in areas without a warfarin clinic. This study analysed national administrative data for reimbursed pharmacy claims to assess OAC prescribing from 2010 to 2017 and compared the use of DOACs in areas with warfarin clinics compared to those without. Over the study period, the number of patients on OAC increased by 84%, due to a rapid increase in DOAC prescribing. The findings demonstrate that DOACs have resulted in an increase in the overall uptake of OAC therapy in Ireland. However, the increased utilisation was not evidently related to populations underserved by warfarin clinics.