Factors associated with non-prescription of oral anticoagulant treatment in non-valvular atrial fibrillation patients with dementia: a CPRD-HES study

Direct Oral Anticoagulant (DOAC) Dosing in Patients with Non-valvular Atrial Fibrillation (NVAF) in the United Kingdom: A Retrospective Cohort Study Using CPRD Gold Database

INTRODUCTION

Per-label dosing of direct oral anticoagulants (DOACs) is important for the prevention of stroke and systemic embolism among patients with non-valvular atrial fibrillation (NVAF), especially those with poor renal function, advanced age, low body weight or concomitant P-glycoprotein inhibitors. The study described DOAC use and dosing patterns in patients with NVAF in the UK.

METHODS

Using Clinical Practice Research Datalink (CPRD Gold), patients' profiles were described at DOAC initiation (1 January 2016-31 March 2021) and followed for a mean [standard deviation (SD)] 2 (1) years. Patients were categorised as under-dosing: received a lower dose with no indication for a reduced dose; over-dosing: received a standard dose with an indication for a reduced dose; per-label dosing, according to Summary Product Characteristics (SmPC).

RESULTS

Forty thousand seven hundred forty-four adult patients with NVAF were identified (mean age: 75.3 (11.2) years; males: 55.4%); 22,827 (56.0%) initiated treatment with apixaban, 930 (2.3%) dabigatran, 5633 (13.8%) edoxaban and 11,354 (27.9%) rivaroxaban. Baseline Charlson comorbidity index ≥ 4 was 65.1%; CHA₂DS₂-VASc score ≥ 4 was 22.5%; HAS-BLED score ≥ 3 was 18.3%; ~ 2% had prior major bleed and 4.4% a stroke ≤ 2 years before DOAC initiation. Overall, 18.0% of patients received incorrect dosing (~ one in five). Under-dosing was highest for dabigatran (156, 16.8%) and over-dosing was highest for rivaroxaban (1084, 9.6%). Per-label dosing was highest for edoxaban (4773, 84.7%), followed by apixaban (18,756, 82.2%), rivaroxaban (9161, 80.7%) and dabigatran (732, 78.7%). Treatment persistence (no switching or discontinuation) was 79% among edoxaban users, followed by 75% for apixaban, 69% for rivaroxaban and 62% for dabigatran. About 15% of dabigatran users, 10% of rivaroxaban users, 5% of apixaban users and 4% of edoxaban users switched treatment to another DOAC during follow-up.

CONCLUSION

Although most patients received per-label dosing, ~ one in five patients was incorrectly dosed with DOAC, which may lead to serious clinical consequences and increased healthcare burden.

[Cognitive impairment in patients with atrial fibrillation]

Atrial fibrillation (AF) is a serious medical and social problem, being a common cause of ischemic stroke (IS) and cognitive impairment (CI), often reaching the degree of dementia. The most common cause of CI in patients with AF is transferred IS or repeated IS. In a significant part of patients with AF who have undergone IS, CI is detected directly in the acute period of the disease and progresses subsequently. In addition, the risk of developing CI is increased even in patients with AF who have not experienced IS before. The review discusses the data on the relationship between CI and AF, provides information on the possible causes of the development of CI in the considered group of patients. The main difficulties of managing a patient with AF and CI are considered.

Trends in Use of Oral Anticoagulants in Older Adults With Newly Diagnosed Atrial Fibrillation, 2010-2020

IMPORTANCE

Undertreatment of older adults with atrial fibrillation with anticoagulation therapy is an important practice gap. It has been posited that the availability of direct oral anticoagulants (DOACs) would improve oral anticoagulant (OAC) initiation in older adults with atrial fibrillation given their superior safety profile compared with warfarin.

OBJECTIVES

To systematically examine trends in OAC initiation and nonadherence in older adults with atrial fibrillation and coexisting geriatric conditions.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study uses administrative claims data from Optum's Clinformatics Data Mart from January 1, 2010, to December 31, 2020. Participants included beneficiaries of Medicare Advantage plans aged 65 years and older with atrial fibrillation and elevated risk of ischemic stroke. Data analysis was performed from October 2021 to October 2022.

EXPOSURES

Coexisting dementia, frailty, and anemia.

MAIN OUTCOMES AND MEASURES

The primary outcomes were OAC initiation within 12 months after the first diagnosis of atrial fibrillation per year and nonadherence with OAC per year (defined as <80% of proportion of days covered among patients newly started on OAC in each year).

RESULTS

There were 21 603 to 51 236 patients per year (total for 2010-2020, 381 488 patients) in the OAC-eligible incident AF cohort (mean [SD] age, 77.2 [6.1] to 77.4 [6.8] years; 13 871 [51.8%] to 22 901 [49.8%] women). OAC initiation within 12 months after incident AF increased from 20.2% (5405 of 26 782 patients) in 2010 to 32.9% (7111 of 21 603 patients) in 2020. DOAC uptake increased from 1.1% (291 of 26 782 patients) to 30.9% (6678 of 21 603 patients), and warfarin initiation decreased from 19.1% (5114 of 26 782 patients) to 2.0% (436 of 21 603 patients). Older age (odds ratio [OR], 0.98; 95% CI, 0.98-0.98), dementia (OR, 0.57; 95% CI, 0.55-0.58), frailty (OR, 0.74; 95% CI, 0.72-0.76), and anemia (OR, 0.75; 95% CI, 0.74-0.77) were associated with lower odds of OAC initiation. During the study period, the median (IQR) proportion of days covered increased from 77.6% (41.0%-96.4%) to 90.2% (57.4%-98.6%), and OAC nonadherence decreased from 52.2% (2290 of 4389 patients) to 39.0% (3434 of 8798 patients).

CONCLUSIONS AND RELEVANCE

Since the introduction of DOACs, OAC initiation in older adults with has improved but remained suboptimal in 2020. Additional strategies are needed to improve stroke prophylaxis in all older adults with atrial fibrillation including those with coexisting dementia, frailty, and anemia.

Control of Therapeutic Levels of Anticoagulation and Associated Factors: A Prospective Cohort Study

Maintaining therapeutic levels of anticoagulation is essential to avoid health complications in people who take vitamin K antagonists. This study aimed to analyze the influence of people's characteristics and the presence of changes in their lives in the control of therapeutic levels of anticoagulation. A longitudinal multicenter study with a 1-year follow-up of a cohort of 199 people receiving anticoagulant therapy was performed. The effect of biological, clinical, social, lifestyle, and changes in life on the international normalized ratio (INR) was analyzed. During the follow-up, 46.7% of participants presented good INR control. At baseline, a diagnosis of atrial fibrillation (P = .00), the lack of comorbidities (P = .03), absence of depression (P = .04), and not following a pharmacological treatment with hypoglycemia drugs (P = .01) were associated with good INR control. During the follow-up, the variable of making changes to the usual diet was associated with poor INR control (P = .05). In the binary multiple regression model, factors associated with poor control were taking hypoglycemia drugs (P = .02) and the presence of depression (P = .04), and only the diagnosis of atrial fibrillation was associated with good control (P = .03). People with a diagnosis of atrial fibrillation had good INR control. Having comorbidities, suffering depression, taking hypoglycemia drugs, and making changes to the diet have a negative effect on INR control.

Incidence of nonvalvular atrial fibrillation and oral anticoagulant prescribing in England, 2009 to 2019: A cohort study

BACKGROUND

Atrial fibrillation (AF) is an important risk factor for ischaemic stroke, and AF incidence is expected to increase. Guidelines recommend using oral anticoagulants (OACs) to prevent the development of stroke. However, studies have reported the frequent underuse of OACs in AF patients. The objective of this study is to describe nonvalvular atrial fibrillation (NVAF) incidence in England and assess the clinical and socioeconomic factors associated with the underprescribing of OACs.

METHODS AND FINDINGS

We conducted a population-based retrospective cohort study using the UK Clinical Practice Research Datalink (CPRD) database to identify patients with NVAF aged ≥18 years and registered in English general practices between 2009 and 2019. Annual incidence rate of NVAF by age, deprivation quintile, and region was estimated. OAC prescribing status was explored for patients at risk for stroke and classified into the following: OAC, aspirin only, or no treatment. We used a multivariable multinomial logistic regression model to estimate relative risk ratios (RRRs) and 95% confidence intervals (CIs) of the factors associated with OAC or aspirin-only prescribing compared to no treatment in patients with NVAF who are recommended to take OAC. The multivariable regression was adjusted for age, sex, comorbidities, socioeconomic status, baseline treatment, frailty, bleeding risk factors, and takes into account clustering by general practice. Between 2009 and 2019, 12,517,191 patients met the criteria for being at risk of developing NVAF. After a median follow-up of 4.6 years, 192,265 patients had an incident NVAF contributing a total of 647,876 person-years (PYR) of follow-up. The overall age-adjusted incidence of NVAF per 10,000 PYR increased from 20.8 (95% CI: 20.4; 21.1) in 2009 to 25.5 (25.1; 25.9) in 2019. Higher incidence rates were observed for older ages and males. Among NVAF patients eligible for anticoagulation, OAC prescribing rose from 59.8% (95% CI: 59.0; 60.6) in 2009 to 83.2% (95% CI: 83.0; 83.4) in 2019. Several conditions were associated with lower risk of OAC prescribing: dementia [RRR 0.52 (0.47; 0.59)], liver disease 0.58 (0.50; 0.67), malignancy 0.74 (0.72; 0.77), and history of falls 0.82 (0.78; 0.85). Compared to white ethnicity, patients from black and other ethnic minorities were less likely to receive OAC; 0.78 (0.65; 0.94) and 0.76 (0.64; 0.91), respectively. Patients living in the most deprived areas were less likely to receive OAC 0.85 (0.79; 0.91) than patients living in the least deprived areas. Practices located in the East of England were associated with higher risk of prescribing aspirin only over no treatment than practices in London (RRR 1.22; 95% CI 1.02 to 1.45). The main limitation of this study is that these findings depends on accurate recording of conditions by health professionals and the inevitable residual confounding due to lack of data on certain factors that could be associated with under-prescribing of OACs.

CONCLUSIONS

The incidence of NVAF increased between 2009 and 2015, before plateauing. Underprescribing of OACs in NVAF is associated with a range of comorbidities, ethnicity, and socioeconomic factors, demonstrating the need for initiatives to reduce inequalities in the care for AF patients.

Stroke risk reassessment and oral anticoagulant initiation in primary care patients with atrial fibrillation: A ten-year follow-up

AIM

To examine the change in stroke risk over time and determine the proportion of patients with atrial fibrillation (AF) who were initiated on an oral anticoagulant (OAC) as their stroke risk increased from low/moderate to high, using the Australian general practice data set, MedicineInsight.

METHODS

A total of 2296 patients diagnosed with AF between 1 January 2007 and 31 December 2008, aged 18 years or older and not initiated on an OAC before 2009, were included. We assessed the change in stroke risk and the proportion of patients who had a recorded prescription of an OAC, each year from 1 January 2009 to 31 December 2018.

RESULTS

At baseline, 23.9%, 22.9% and 53.2% were categorised as being at low (score = 0), moderate (score = 1) and high stroke risk (score ≥ 2), respectively, using the sexless CHA₂ DS₂ -VASc (CHA₂ DS₂ -VA) score. Overall, the CHA₂ DS₂ -VA score increased by a mean of 1.34 (95% confidence interval, 1.29-1.39) points over the study period. Nearly two-thirds of patients (65%, 412/632) whose stroke risk changed from baseline low/moderate to high were subsequently prescribed an OAC. The median (interquartile range) lag time from becoming high stroke risk to having OAC initiation was 2 (5) years.

CONCLUSIONS

Nearly one-third of patients reclassified as being at high risk of stroke during the study period were not prescribed OAC therapy. Furthermore, the delay in OAC initiation following classification as being at high risk was a median of 2 years, suggesting that more frequent stroke reassessment is needed.

Underprescription of medications in older adults: causes, consequences and solutions-a narrative review

PURPOSE

Under-prescription is defined as the omission of a medication that is indicated for the treatment of a condition or a disease, without any valid reason for not prescribing it. The aim of this review is to provide an updated overview of under-prescription, summarizing the available evidence concerning its prevalence, causes, consequences and potential interventions to reduce it.

METHODS

A PubMed search was performed, using the following keywords: under-prescription; under-treatment; prescribing omission; older adults; polypharmacy; cardiovascular drugs; osteoporosis; anticoagulant. The list of articles was evaluated by two authors who selected the most relevant of them. The reference lists of retrieved articles were screened for additional pertinent studies.

RESULTS

Although several pharmacological therapies are safe and effective in older patients, under-prescription remains widespread in the older population, with a prevalence ranging from 22 to 70%. Several drugs are underused, including cardiovascular, oral anticoagulant and anti-osteoporotic drugs. Many factors are associated with under-prescription, e.g. multi-morbidity, polypharmacy, dementia, frailty, risk of adverse drug events, absence of specific clinical trials in older patients and economic factors. Under-prescription is associated with negative consequences, such as higher risk of cardiovascular events, worsening disability, hospitalization and death. The implementation of explicit criteria for under-prescription, the use of the comprehensive geriatric assessment by geriatricians, and the involvement of a clinical pharmacist seem to be promising options to reduce under-prescription.

CONCLUSION

Under-prescription remains widespread in the older population. Further studies should be performed, to provide a better comprehension of this phenomenon and to confirm the efficacy of corrective interventions.

Effectiveness and Safety of Oral Anticoagulants in Older Patients With Atrial Fibrillation: A Systematic Review and Meta-Analysis

Background and Objective

Atrial fibrillation (AF), the most common cardiac arrhythmia, typically increases with age. Oral anticoagulants (OACs) are the cornerstone of treatment to reduce the associated risk for systemic thromboembolism. Four large randomized controlled trials (RCTs) have shown that non-vitamin K antagonist oral anticoagulants (NOACs) are non-inferior to vitamin K antagonists (VKAs) in preventing stroke and systemic embolism, as well as regarding their risk for major bleeding. However, as vulnerable geriatric patients with AF were largely underrepresented in these trials, physicians are faced with the challenge of choosing the right anticoagulant for geriatric patients in real-life clinical practice. In this vulnerable patient group, NOACs tend to be underused or underdosed due to concerns of excessive fall-related intracranial bleeding, cognitive impairment, multiple drug-drug interactions, low body weight or impaired renal function. As life expectancy continues to rise worldwide, the number of geriatric patients substantially increases. Therefore, there is an urgent need for a critical appraisal of the added value of NOACs in geriatric patients with AF at high thromboembolic and bleeding risk.

Methods and Results

This systematic review provides an overview of the literature on the impact of increased age (≥75 years), multimorbidity, polypharmacy, increased falling risk, frailty and dementia on the effectiveness and safety of NOACs as compared to VKAs, after searching the Medline database. Moreover, a meta-analysis on the impact of increased age ≥75 years old was performed after pooling results from 6 post hoc analyses of RCTs and 6 longitudinal observational cohort studies, highlighting the superior effectiveness (hazard ratio (HR) 0.83, 95% confidence interval (CI) [0.74–0.94] for stroke/SE; HR 0.77, 95%CI [0.65–0.92] for mortality) and non-inferior safety (HR 0.93, 95%CI [0.86–1.01] for major bleeding; HR 0.58, 95%CI [0.50–0.67] for intracranial bleeding; HR 1.17, 95%CI [0.99–1.38] for gastrointestinal bleeding) of NOACs versus VKAs in older AF patients.

Conclusion

Across geriatric subgroups, apixaban was consistently associated with the most favourable benefit-risk profile and should therefore be preferred in geriatric patients with AF. However, research gaps on the impact of increased falling risk, frailty and baseline dementia were identified, requiring careful consideration while awaiting more results.