Antithrombotic therapy in patients with non-valvular atrial fibrillation in Southern Sweden: A population-based cohort study

Prevalence of atrial fibrillation and reasons for undertreatment with oral anticoagulants

OBJECTIVES

To investigate the prevalence of atrial fibrillation (AF), the proportion of AF patients not receiving oral anticoagulation (OAC) and reasons for abstaining from OAC treatment.

METHODS

A retrospective cross-sectional study of patients aged 18 years or older with an AF diagnosis on June 1st 2020 in Västernorrland County, Sweden. AF diagnosis was retrieved using the ICD10 code I.48, and medical records were reviewed for comorbidities and documented reasons to abstain OAC treatment.

RESULTS

Of 197 274 residents in Västernorrland County, 4.7% (9 304/197 274) had a documented AF diagnosis. Of these, 19% (1 768/9 304) had no OAC treatment, including 4.2% (393/9 304) with no indication, 2.5% (233/9 304) with a questionable and 2.5% (231/9 304) with a documented clear contraindication for OAC. In total 9.8% (911/9 304) were not treated with OAC despite indication and no reasonable documented contraindication, thus 90.8% (8 447/9 304) of all AF-patients were eligible for OAC treatment. Common reasons for abstaining treatment without reasonable contraindication were present sinus rhythm in 13.7% (125/911), perceived not an OAC candidate in 10.6% (97/911) and anemia in the past in 4.3% (39/911).

CONCLUSIONS

In the population of Västernorrland County, a very high AF prevalence of 4.7% was found, of which just over 90% would theoretically benefit from OAC treatment. This is higher than previously reported and stresses the importance of stroke prevention in this large patient group.

Worldwide trends in oral anticoagulant use in patients with atrial fibrillation from 2010 to 2018: a systematic review and meta-analysis

AIMS

Non-vitamin K antagonist oral anticoagulants (NOACs) are effective and safe alternatives compared with vitamin K antagonists (VKAs) for thromboembolic prevention in atrial fibrillation (AF), while antiplatelets are no longer recommended. However, to which extent NOAC introduction and guideline updates have increased OAC use in AF, is unclear. Therefore, worldwide trends in real-life prescribing of OACs, NOACs, VKAs, and antiplatelet monotherapy in AF patients were investigated.

METHODS AND RESULTS

Using PubMed and Embase, observational nationwide cohort studies on annual prevalent and/or incident OAC use in non-selected AF patients since 2010 were included. A meta-analysis of single proportions was performed. Twenty-one studies were included assessing prevalent and incident use among 9 758 637 and 197 483 OAC-eligible AF patients, respectively. Worldwide prevalence and incidence of OAC users increased from 0.42 [95% confidence interval (CI) 0.22-0.65] and 0.43 (95% CI 0.37-0.49) in 2010 to 0.78 (95% CI 0.77-0.78) and 0.75 (95% CI 0.74-0.76) in 2018, respectively. Prevalent and incident NOAC users increased globally from 0 in 2010 to 0.45 (95% CI 0.45-0.46) and 0.68 (95% CI 0.67-0.69) in 2018, respectively, whereas prevalent and incident VKA use decreased from 0.42 (95% CI 0.22-0.65) and 0.42 (95% CI 0.36-0.49) in 2010 to 0.32 (95% CI 0.32-0.32) and 0.06 (95% CI 0.06-0.07) in 2018, respectively. Prevalent antiplatelet monotherapy use decreased from 0.37 (95% CI 0.32-0.42) in 2010 to 0.09 (95% CI 0.09-0.10) in 2018.

CONCLUSION

The proportion of OAC users worldwide almost doubled following NOAC introduction. As one-quarter of OAC-eligible AF subjects were not anticoagulated and 9% were only treated with antiplatelets in 2018, there is still room for improvement.

Strategies for improving guideline adherence of anticoagulants for patients with atrial fibrillation in primary healthcare: A systematic review

BACKGROUND

Clinical guidelines on atrial fibrillation management help optimize the use of oral anticoagulants. However, guideline non-adherence is common, particularly in the primary care setting. The primary aim of this systematic review was to identify effective strategies for improving adherence to guideline-directed thromboprophylaxis to patients with atrial fibrillation in the primary care setting.

METHODS

A search was conducted on 6 electronic databases (Medline, Embase, ScienceDirect, Scopus, the Cumulative Indexing of Nursing and Allied Health Literature, and Web of Science) supplemented by a Google advanced search. Studies aimed at improving oral thromboprophylaxis guideline adherence in patients with atrial fibrillation, in the primary care setting, were included in the study.

RESULTS

A total of 33 studies were included in this review. Nine studies employed electronic decision support (EDS), of which 4 reported modest improvements in guideline adherence. Five of 6 studies that utilized local guidelines as quality improvement measures reported improvement in guideline adherence. All 5 studies that employed coordinated care and the use of specialist support and 4 of the 5 studies that involved pharmacist-led interventions reported improvements in guideline adherence. Interventions based mainly on feedback from audits were less effective.

CONCLUSIONS

Multifaceted interventions, especially those incorporating coordinated care and specialist support, pharmacists, or local adaptations to and implementation of national and/or international guidelines appear to be more consistently effective in improving guideline adherence in the primary care setting than interventions based mainly on EDS and feedback from audits.

Non-adherence to Thromboprophylaxis Guidelines in Atrial Fibrillation: A Narrative Review of the Extent of and Factors in Guideline Non-adherence

Atrial fibrillation is the most common arrhythmia. It increases the risk of thromboembolism by up to fivefold. Guidelines provide evidence-based recommendations to effectively mitigate thromboembolic events using oral anticoagulants while minimizing the risk of bleeding. This review focuses on non-adherence to contemporary guidelines and the factors associated with guideline non-adherence. The extent of guideline non-adherence differs according to geographic region, healthcare setting, and risk stratification tools used. Guideline adherence has gradually improved over recent years, but a significant proportion of patients are still not receiving guideline-recommended therapy. Physician-related and patient-related factors (such as patient refusals, bleeding risk, older age, and recurrent falls) also contribute to guideline non-adherence, especially to undertreatment. Quality improvement initiatives that focus on undertreatment, especially in the primary healthcare setting, may help to improve guideline adherence.

The value of the Skåne Health-care Register: Prospectively collected individual-level data for population-based studies

Aims: This study aimed to examine the population-based Skåne Health-care Register (SHR) regarding feasibility for scientific research and also strengths and weaknesses. Methods: To analyse the feasibility of the SHR, we performed a bibliographic search for peer-reviewed articles based on SHR data from 2000 to 2018. To analyse strengths and weaknesses, we used original SHR data about coverage and validity. Results: We identified 58 articles based on SHR data, covering different study designs and disorders. Most studies focused on musculoskeletal disorders with a cohort design. The majority of all consultations recorded in the SHR have an assigned diagnosis. However, this differs between the levels of care and between types of consultation. For inpatient care, the proportion of consultations with an assigned diagnosis was close to 100% between 1998 and 2017. The proportion of consultations with an assigned diagnosis was lowest within primary care, although the proportion markedly increased in 2004 when the prerequisite for consultation reimbursement was linked to the requirement for an assigned diagnosis. Limitations are that the SHR does not cover health-care provided within nursing homes and equivalent facilities or treatments received by the population of Skåne outside the region. Conclusions: The SHR may be used as a reliable data source for analyses of clinical changes and improvements. Extended use of the SHR in a research context may highlight important shortcomings within the register and thus serve as a way of indirect quality control. To enhance the use of the SHR further, better harmonisation between registers, within and outside of the region and internationally, is of crucial importance.

Comparative effectiveness of warfarin, dabigatran, rivaroxaban and apixaban in non-valvular atrial fibrillation: A nationwide pharmacoepidemiological study

OBJECTIVE

To compare effectiveness and safety of warfarin and the direct oral anticoagulants (DOAC) dabigatran, rivaroxaban and apixaban in non-valvular atrial fibrillation in routine care.

METHODS

From nationwide registries, we identified treatment-naïve patients initiating warfarin, dabigatran, rivaroxaban or apixaban for non-valvular atrial fibrillation from July 2013 to December 2015 in Norway. We assessed prescription duration using reverse waiting time distribution. Adjusting for confounding in a Cox proportional hazards model, we estimated one-year risks for ischemic stroke, transient ischemic attack (TIA) or systemic embolism, major or clinically relevant non-major bleeding; intracranial; gastrointestinal; and other bleeding. We censored at switch of treatment or 365 days of follow-up.

RESULTS

We included 30,820 treatment-naïve patients. Compared to warfarin, the adjusted hazard ratios (HR) for ischemic stroke, TIA or systemic embolism were 0.96 (95% CI 0.71-1.28) for dabigatran, 1.12 (95% CI 0.87-1.45) for rivaroxaban and 0.97 (95% CI 0.75-1.26) for apixaban. Corresponding hazard ratios for major or clinically relevant non-major bleeding were 0.73 (95% CI 0.62-0.86) for dabigatran, 0.97 (95% CI 0.84-1.12) for rivaroxaban and 0.71 (95% CI 0.62-0.82) for apixaban. Statistically significant differences of other safety outcomes compared to warfarin were fewer intracranial bleedings with dabigatran (HR 0.28, 95% CI 0.14-0.56), rivaroxaban (HR 0.40, 95% CI 0.23-0.69) and apixaban (HR 0.56, 95% CI 0.34-0.92); fewer gastrointestinal bleedings with apixaban (HR 0.70, 95% CI 0.52-0.93); and fewer other bleedings with dabigatran (HR 0.67, 95% CI 0.55-0.81) and apixaban (HR 0.70, 95% CI 0.59-0.83).

CONCLUSION

After 1 year follow-up in treatment-naïve patients initiating oral anticoagulation for non-valvular atrial fibrillation, all DOACs were similarly effective as warfarin in prevention of ischemic stroke, TIA or systemic embolism. Safety from bleedings was similar or better, including fewer intracranial bleedings with all direct oral anticoagulants, fewer gastrointestinal bleedings with apixaban and fewer other bleedings with dabigatran and apixaban.

Poor outcomes associated with antithrombotic undertreatment in patients with atrial fibrillation attending Gondar University Hospital: a retrospective cohort study

BACKGROUND

Atrial fibrillation (AF) is a major risk factor for stroke as it increases the incidence of stroke nearly fivefold. Antithrombotic treatment is recommended for the prevention of stroke in AF patients. However, majorly due to fear of risk of bleeding, adherence to recommendations is not observed. The aim of this study was to investigate the impact of antithrombotic undertreatment, on ischemic stroke and/or all-cause mortality in patients with AF.

METHODS

A retrospective cohort study was conducted from January 7, 2017 to April 30 2017 using medical records of patients with AF attending Gondar University Hospital (GUH) between November 2012 and September 2016. Patients receiving appropriate antithrombotic management and those on undertreatment, were followed for development of ischemic stroke and/or all-cause mortality. Kaplan-Meier and a log-rank test was used to plot the survival analysis curve. Cox regression was used to determine the predictors of guideline-adherent antithrombotic therapy.

RESULTS

The final analysis included 159 AF patients with a median age of 60 years. Of these, nearly two third (64.78%) of patients were receiving undertreatment for antithrombotic medications. Upon multivariate analysis, history of ischemic stroke/transient ischemic attack (TIA) was associated with lower incidence of antithrombotic undertreatment. A significant increase (HR: 8.194, 95% CI: 2.911-23.066)] in the incidence of ischemic stroke and/or all-cause mortality was observed in patients with undertreatment. Up-on multivariate analysis, only increased age was associated with a statistically significant increase incidence of ischemic stroke and/or all-cause mortality, while only history of ischemic stroke/TIA was associated with a decrease in the risk of ischemic stroke and/or all-cause mortality.

CONCLUSION

Adherence to antithrombotic guideline recommendations was found to be crucial in reducing the incidence of ischemic stroke and/or all-cause mortality in patients with AF without increasing the risk of bleeding. However, undertreatment to antithrombotic medications was found to be high (64.78%) and was associated with poorer outcomes in terms of ischemic stroke and/or all-cause mortality. Impact on practice: This research highlighted the magnitude of antithrombotic undertreatment and its impact on ischemic stroke and/or all-cause mortality in patients with AF. This article has to alert prescribers to routinely evaluate AF patients' risk for ischemic stroke and provide appropriate interventions based on guideline recommendations.

Antithrombotic therapies for elderly patients: handling problems originating from their comorbidities

Compared with younger people, elderly people have higher risks for both thrombosis and bleeding. Furthermore, comorbidities frequently found in elderly patients complicate the management of antithrombotic therapy. Thus, when treating these patients, physicians often find it difficult to incorporate the principles of evidence-based medicine and must determine the best treatment option for each patient. Recently, in the fields of cerebrovascular and cardiovascular diseases, researchers have been rapidly accumulating new data regarding antithrombotic therapy, particularly in the areas of direct oral anticoagulants (DOACs) and dual antiplatelet therapy (DAPT). However, information related to elderly patients receiving antithrombotic therapy is still relatively limited. There are also more and more publications describing how antithrombotic therapy affects the pathogenesis of non-thrombotic diseases. Similarly, the number of reports concerning adherence to this therapy has been increasing lately. However, no review articles detailing these findings have yet been published. In actual clinical practice, antithrombotic therapy in the elderly is not a treatment strategy targeted to only one organ or disease. Rather, it requires an interdisciplinary approach aimed at maintaining the overall health of the patient. Thus, to assist physicians’ decision-making processes for elderly patients, an overview of recent findings related to the evidence regarding concomitant medications, the secondary benefits of antithrombotic therapy for patients with comorbidities, and evidence regarding medication adherence is provided.

Incidence, predictive factors, management, and survival impact of atrial fibrillation in non-Hodgkin lymphoma

Atrial fibrillation (AF) and cancer are common disorders in the general population but there are few studies in patients with both diseases. More specifically, there are scarce data on AF in patients with non-Hodgkin lymphoma (NHL). We assessed the incidence, predictive factors, management, and survival impact of AF in a cohort of patients with NHL from a single institution between 2002 and 2016 (n = 747). Twenty-three patients were diagnosed with AF before and 40 after the diagnosis of NHL (of the later, 16 were secondary to an extracardiac comorbidity and 24 unrelated to any triggering event [primary AF]). The 5-year cumulative incidence of new-onset AF was 4% (95% confidence interval [CI] 3-6%). Age and hypertension were the only predictive factors for the development of AF. Management of AF was heterogeneous, primarily with anti-vitamin K agents but also antiplatelet therapy in a significant proportion of patients. Among the 63 patients, there were six episodes of ischemic stroke/transient ischemic attack and four venous thromboembolic events, with four major bleeding episodes. Overall survival (OS) was inferior in patients with AF (HR 0.1, 95% CI 0.01-0.7, p = 0.02), largely due to secondary AF. We conclude that the incidence of new-onset AF in NHL patients seemed somewhat higher than in the general population, although with similar predictive factors. The management was heterogeneous, and the risk of ischemic and hemorrhagic events did not seem higher than in cancer-free patients. Survival was particularly poor for patients with secondary AF.

Trends in initiation of direct oral anticoagulant therapies for atrial fibrillation in a national population-based cross-sectional study in the French health insurance databases

OBJECTIVE

Unlike several other national health agencies, French health authorities recommended that the newer direct oral anticoagulant (DOAC) agents only be prescribed as second choice for the treatment of newly diagnosed non-valvular atrial fibrillation (NVAF), with vitamin K antagonists (VKA) remaining the first choice. We investigated the patterns of use of DOACs versus VKA in the treatment of NVAF in France over the first 5 years of DOAC availability. We also identified the changes in patient characteristics of those who initiated DOAC treatment over this time period.

METHODS

Based on the French National Health Administrative Database, we constituted a population-based cohort of all patients who were newly treated for NVAF between January 2011 and December 2015. Trends in drug use were described as the percentage of patients initiating each drug at the time of treatment initiation. A multivariate analysis using logistic regression model was performed to identify independent sociodemographic and clinical predictors of initial anticoagulant choice.

RESULTS

The cohort comprised 814 446 patients who had received a new anticoagulant treatment for NVAF. The proportion of patients using DOACs as initial anticoagulant therapy reached 54% 3 months after the Health Ministry approved the reimbursement of dabigatran for NVAF, and 61% by the end of 2015, versus VKA use. In the multivariate analysis, we found that DOAC initiators were younger and healthier overall than VKA initiators, and this tendency was reinforced over the 2011-2014 period. DOACs were more frequently prescribed by cardiologists in 2012 and after (adjusted OR in 2012: 2.47; 95% CI 2.40 to 2.54).

CONCLUSION

Despite recommendations from health authorities, DOACs have been rapidly and massively adopted as initial therapy for NVAF in France. Observational studies should account for the fact that patients selected to initiate DOAC treatment are healthier overall, as failure to do so may bias the risk-benefit assessment of DOACs.

Real world adherence to oral anticoagulant in non-valvular atrial fibrillation patients in China

BACKGROUND AND OBJECTIVE

Adherence to oral anticoagulants is crucial for the prevention of ischemic stroke in atrial fibrillation patients; however, evidence of oral-anticoagulant adherence from developing countries is still lacking. This study aimed to evaluate the current situation and predictors of oral-anticoagulant adherence in non-valvular atrial fibrillation (NVAF) patients in China.

METHODS

Records of NVAF patients were obtained from a regional claims database. Both initiation and adherence to oral anticoagulants were calculated from linked records. Factors of oral-anticoagulant initiation were identified using Cox regression.

RESULTS

Among 33,463 NVAF patients, only 13.9% initialized warfarin treatment after the indexed hospital visit. Stratified by CHA₂DS₂-VASc scores, 20.9% of patients in the low-risk group were on warfarin, followed by 15.3% and 10.7% from the middle and high-risk groups, respectively. Among patients who initialized warfarin, only 40.4% filled the first repeat prescription within 3 months. Concurrent statin use, hypertension and heart failure were associated with higher warfarin initiation rate. Factors such as age above 75, female sex, manufacture workers, discharge from the primary-care center, antiplatelet use, and diabetes, ischemic and hemorrhagic stroke were associated with lower rate of warfarin initiation. Additionally, initiating warfarin treatment reduced risk of ischemic stroke in middle and high-risk patients.

CONCLUSION

Oral anticoagulation was significantly under-used in NVAF patients in China. Age, sex, concurrent drug usage, and disease history were associated factors. Improving warfarin adherence was promising to reduce ischemic stroke risk of NVAF patients.

Oral anticoagulation therapy upon discharge in hospitalized patients with nonvalvular atrial fibrillation: a retrospective cohort study

OBJECTIVES

Availability of direct oral anticoagulants and CHA₂DS₂VASc/HAS-BLED scoring tools underscore the importance of appropriate and safe use of oral anticoagulation therapy (OACT). The purpose of this study was to evaluate stroke prevention pharmacotherapy in adult patients with nonvalvular atrial fibrillation (NVAF) discharged from a large, community-based hospital.

METHODS

A retrospective cohort study was conducted using a de-identified data collection sheet for data extraction (demographics, admitting diagnosis, OACT prior to admission and at discharge, concomitant medications that could increase bleed risk and/or acid-suppressive therapies). CHA₂DS2VASc and HAS-BLED scores were calculated. Descriptive statistics were generated to describe all parameters. Frequency counts and percentages summarized categorical variables while mean ± standard deviation were determined for continuous variables.

RESULTS

Data from 180 patients were evaluated and of these 177 (98.3%) received OACT regardless of stroke risk upon discharge, as determined by CHA₂DS₂VASc scoring tool. The mean CHA₂DS₂VASc and HAS-BLED scores were 3.61 ± 1.7 and 2.13 ± 1.26, respectively. At discharge, eight patients at low-stroke risk received OACT for unclear reasons, one intermediate-stroke risk patient received aspirin only, and two patients at high-stroke risk did not receive OACT due to concerns about bleeds. In 66 patients at high-bleed risk, only half received concomitant acid-suppressive therapy.

CONCLUSIONS

Decision to add OACT is often guideline-driven, however, individualized circumstances in which clinicians and patients find themselves are also important considerations. Determination of ischemic stroke risk should be performed with CHA₂DS₂VASc scoring tool to exclude patients who may not benefit from OACT. HAS-BLED scoring tool should be used to identify any modifiable bleeding risk factors present with subsequent initiation of management strategies. Availability of complete medical histories and meticulous documentation are necessary for multiple clinicians to continuously determine optimal pharmacotherapy during follow-up visits.

Real-practice thromboprophylaxis in atrial fibrillation

This retrospective observational study was based on databases of the Local Health Authority of Treviso, Italy. It evaluated the prevalence and the effectiveness of oral anticoagulation treatment (OAT) for the management of nonvalvular atrial fibrillation (NVAF) in everyday clinical practice. Out of 6,138 NVAF patients, only 3,024 received vitamin K antagonist (VKA). Potential barriers decreasing the probability of being treated with VKA were female sex, older age, antiplatelet treatment and history of bleeding. In addition, VKA-treatment was not in line with current ESC and AIAC guidelines, since the patients at high or low risk of stroke were under- or over-treated, resp. Among VKAtreated patients, 73 % of subjects were not at target with anticoagulation. OAT resulted to be effective in reducing stroke risk. However, stroke events were significantly influenced also by previous stroke or transient ischemic attack (hazard ratio, HR = 2.99, p < 0.001) and by previous bleeding events (HR = 1.60, p < 0.001).

Short-Term Risk of Bleeding During Heparin Bridging at Initiation of Vitamin K Antagonist Therapy in More Than 90 000 Patients With Nonvalvular Atrial Fibrillation Managed in Outpatient Care

Background

Several studies have recently examined the risks of bleeding and of ischemic stroke and systemic embolism associated with perioperative heparin bridging anticoagulation in patients with nonvalvular atrial fibrillation. However, few studies have investigated bridging risks during vitamin K antagonist initiation in outpatient settings.

Methods and Results

A retrospective cohort study was conducted on individuals starting oral anticoagulation between January 2010 and November 2014 for nonvalvular atrial fibrillation managed in outpatient care and identified from French healthcare insurance. Bleeding and ischemic stroke and systemic embolism events were identified from the hospitalization database. Adjusted hazard ratios with 95% CI were estimated using Cox models during the first and 2 following months of anticoagulation. Of 90 826 individuals, 30% had bridging therapy. A total of 318 (0.35%) cases of bleeding and 151 (0.17%) ischemic stroke and systemic embolism cases were identified during the first month of follow‐up and 231 (0.31%) and 122 (0.16%) during the 2 following months, respectively. At 1 month of follow‐up, the incidence of bleeding was higher in the bridged group compared with the nonbridged group (0.47% versus 0.30%; P<0.001), and this increased risk persisted after adjustment for covariates (hazard ratio=1.60; 95% CI, 1.28–2.01). This difference disappeared after the first month of treatment (0.93; 0.70–1.23). No significant difference in the occurrence of ischemic stroke and systemic embolism was observed either at 1 month of follow‐up or later.

Conclusions

At vitamin K antagonist initiation for nonvalvular atrial fibrillation managed in ambulatory settings, bridging therapy is associated with a higher risk of bleeding and a similar risk of arterial thromboembolism compared with no bridging therapy.