Warfarin for prevention of thrombosis among long-term care residents with atrial fibrillation: evidence of continuing low use despite consideration of stroke and bleeding risk

Prescribing of anticoagulation for atrial fibrillation in primary care

Atrial fibrillation (AF) is common in primary care patients. Many patients who could benefit from anticoagulation do not receive it. The objective of this study was to describe anticoagulation prescribing by primary care physicians. We conducted an observational study in the Cleveland Clinic Health System among patients with AF and ≥ 1 primary care appointment between 2015 and 2018 and their physicians. We estimated differences in the odds of an eligible patient receiving anticoagulation versus not and a DOAC versus warfarin using two mixed effects logistic regression models, adjusted for patient sociodemographic factors, history of falls or dementia, and CHA2DS2-VASc and HAS-BLED scores. We categorized physicians into prescribing tertiles, based on their adjusted prescribing rate, which we included as predictors in the models. Among 5253 patients, 47% received anticoagulation. Of those, 56% received a DOAC. CHA2DS2-VASc and HAS-BLED scores were not associated with anticoagulation prescription. Black race was negatively associated with receiving anticoagulation overall (aOR:0.71; 95%CI:0.56-0.89) and with prescription for a DOAC (aOR:0.65; 95%CI:0.45-0.93). Among 195 physicians, the anticoagulation prescribing rate ranged from 27% to 57% and DOAC rates ranged from 34% to 69%. Physician prescribing tertile was associated with odds of a patient receiving anticoagulation overall (aOR:1.51; 95%CI: 1.13-2.01 for the highest versus lowest tertile), but not DOAC prescriptions. When prescribing anticoagulation, physicians appear not to consider risk of stroke or bleeding but patient race is an important determinant. Seeing a physician with a high anticoagulation prescribing rate was strongly associated with a patient receiving it, suggesting a lack of individualization.

Prevalence, management and impact of chronic obstructive pulmonary disease in atrial fibrillation: a systematic review and meta-analysis of 4,200,000 patients

AIM

Prevalence of chronic obstructive pulmonary disease (COPD) in atrial fibrillation (AF) patients is unclear, and its association with adverse outcomes is often overlooked. Our aim was to estimate the prevalence of COPD, its impact on clinical management and outcomes in patients with AF, and the impact of beta-blockers (BBs) on outcomes in patients with COPD.

METHODS AND RESULTS

A systematic review and meta-analysis was conducted according to international guidelines. All studies reporting the prevalence of COPD in AF patients were included. Data on comorbidities, BBs and oral anticoagulant prescription, and outcomes (all-cause death, cardiovascular (CV) death, ischaemic stroke, major bleeding) were compared according to COPD and BB status. Among 46 studies, pooled prevalence of COPD was 13% [95% confidence intervals (CI) 10-16%, 95% prediction interval 2-47%]. COPD was associated with higher prevalence of comorbidities, higher CHA2DS2-VASc score and lower BB prescription [odds ratio (OR) 0.77, 95% CI 0.61-0.98]. COPD was associated with higher risk of all-cause death (OR 2.22, 95% CI 1.93-2.55), CV death (OR 1.84, 95% CI 1.39-2.43), and major bleeding (OR 1.45, 95% CI 1.17-1.80); no significant differences in outcomes were observed according to BB use in AF patients with COPD.

CONCLUSION

COPD is common in AF, being found in 13% of patients, and is associated with increased burden of comorbidities, differential management, and worse outcomes, with more than a two-fold higher risk of all-cause death and increased risk of CV death and major bleeding. Therapy with BBs does not increase the risk of adverse outcomes in patients with AF and COPD.

Prevalence of atrial fibrillation and outcomes in older long-term care residents: a systematic review

BACKGROUND

anticoagulation is integral to stroke prevention for atrial fibrillation (AF), but there is evidence of under-treatment in older people in long-term care (LTC).

OBJECTIVE

to synthesise evidence on the prevalence and outcomes (stroke, mortality or bleeding) of AF in LTC and the factors associated with the prescription of anticoagulation.

METHODS

studies were identified from Medline, CINAHL, PsycINFO, Scopus and Web of Science from inception to 31 October 2019. Two reviewers independently applied the selection criteria and assessed the quality of studies using the Newcastle Ottawa Scale.

RESULTS

twenty-nine studies were included. Prevalence of AF was reported in 21 studies, ranging from 7 to 38%. Two studies reported on outcomes based on the prescription of anticoagulation or not; one reported a reduction in the ischaemic stroke event rate associated with anticoagulant (AC) prescription (2.84 per 100 person years, 95% confidence interval [CI]: 1.98-7.25 versus 3.95, 95% CI: 2.85-10.08) and a non-significant increase in intracranial haemorrhage rate (0.71 per 100 person years, 95% CI: 0.29-2.15 versus 0.65, 95% CI: 0.29-1.93). The second study reported a 76% lower chance of ischaemic stroke with AC prescription and a low incidence of bleeding (n = 4 events). Older age, dementia/cognitive impairment and falls/falls risk were independently associated with the non-prescription of anticoagulation. Conversely, previous stroke/transient ischaemic attack and thromboembolism were independently associated with an increased prescription of anticoagulation.

CONCLUSION

estimates of AF prevalence and factors associated with AC prescription varied extensively. Limited data on outcomes prevent the drawing of definitive conclusions. We recommend panel data collection and systems for linkage to create longitudinal cohorts to provide more robust evidence.

Trends in Anticoagulant Use at Nursing Home Admission and Variation by Frailty and Chronic Kidney Disease Among Older Adults with Atrial Fibrillation

BACKGROUND

Atrial fibrillation (AF) is relatively common among nursing home residents, and decisions regarding anticoagulant therapy in this setting may be complicated by resident frailty and other factors.

OBJECTIVES

The aim of this study was to examine trends and correlates of oral anticoagulant use among newly admitted nursing home residents with AF following the approval of direct-acting oral anticoagulants (DOACs).

METHODS

We conducted a retrospective cohort study of all adults aged > 65 years with AF who were newly admitted to nursing homes in Ontario, Canada, between 2011 and 2018 (N = 36,466). Health administrative databases were linked with comprehensive clinical assessment data captured shortly after admission, to ascertain resident characteristics. Trends in prevalence of anticoagulant use (any, warfarin, DOAC) at admission were captured with prescription claims and examined by frailty and chronic kidney disease (CKD). Log-binomial regression models estimated crude percentage changes in use over time and modified Poisson regression models assessed factors associated with anticoagulant use and type.

RESULTS

The prevalence of anticoagulant use at admission increased from 41.1% in 2011/2012 to 58.0% in 2017/2018 (percentage increase = 41.1%, p < 0.001). Warfarin use declined (- 67.7%, p < 0.001), while DOAC use increased. Anticoagulant use was less likely among residents with a prior hospitalization for hemorrhagic stroke (adjusted risk ratio [aRR] 0.65, 95% confidence interval [CI] 0.60-0.70) or gastrointestinal bleed (aRR 0.80, 95% CI 0.78-0.83), liver disease (aRR 0.78, 95% CI 0.69-0.89), severe cognitive impairment (aRR 0.89, 95% CI 0.85-0.94), and non-steroidal anti-inflammatory drug (aRR 0.76, 95% CI 0.71-0.81) or antiplatelet (aRR 0.25, 95% CI 0.23-0.27) use, but more likely for those with a prior hospitalization for ischemic stroke or thromboembolism (aRR 1.30, 95% CI 1.27-1.33). CKD was associated with a reduced likelihood of DOAC versus warfarin use in both the early (aRR 0.62, 95% CI 0.54-0.71) and later years (aRR 0.79, 95% CI 0.76-0.83) of our study period. Frail residents were significantly less likely to receive an anticoagulant at admission, although this association was modest (aRR 0.95, 95% CI 0.92-0.98). Frailty was not associated with anticoagulant type.

CONCLUSIONS

While the proportion of residents with AF receiving oral anticoagulants at admission increased following the approval of DOACs, over 40% remained untreated. Among those treated, use of a DOAC increased, while warfarin use declined. The impact of these recent treatment patterns on the balance between benefit and harm among residents warrant further investigation.

Healthcare resource utilization and costs among nonvalvular atrial fibrillation patients initiating rivaroxaban or warfarin in skilled nursing facilities: a retrospective cohort study

Objective: Atrial fibrillation (AF) is present in up to 17% of patients in skilled nursing facilities (SNFs). This study compared healthcare resource utilization (HRU) and costs between AF patients initiating rivaroxaban or warfarin in SNFs.Methods: Using de-identified claims from Optum Clinformatics Extended Data Mart (1 January 2013 to 31 December 2017), this retrospective cohort study indexed AF patients with first SNF admission during which rivaroxaban or warfarin was initiated within 3 days of admission. To adjust for selection bias, inverse probability of treatment weighting (IPTW) was applied for baseline characteristics. Logistic regression and generalized linear models were used to compare HRU and costs.Results: 519 rivaroxaban and 1129 warfarin patients met inclusion criteria. After IPTW, the cohorts were well balanced for baseline characteristics. The average length of index SNF stay was 32.07 and 37.44 days for rivaroxaban and warfarin patients, respectively. During SNF stay, rivaroxaban patients had 27% lower odds of hospitalization (p < .0001), 2.7 fewer international normalized ratio (INR) tests per-patient-per-month (PPPM; p < .001), and 2.3 fewer pathology/laboratory encounters PPPM (p < .0001) than warfarin patients. All-cause healthcare costs were $2638 lower with rivaroxaban versus warfarin (p < .0001) during the index SNF stay, with lower medical costs (p < .0001) but higher pharmacy costs (p < .0001). Total all-cause healthcare costs 100 days post-index SNF were $8746 lower with rivaroxaban versus warfarin (p < .0001).Conclusions: In the SNF setting, AF patients treated with rivaroxaban had 5-day shorter length of stay, lower HRU, and lower all-cause total and medical costs compared to warfarin, despite higher treatment costs. These findings may help inform clinical decision-making to reduce economic burden.

Assessment of Oral Anticoagulant Use in Residents of Long-Term Care Homes: Evidence for Contemporary Suboptimal Use

Objective: To describe the quality of warfarin use in residents of long-term care facilities and investigate potential predictors oral anticoagulant use. Design: Retrospective chart review (August 2013 to September 2014). Setting: Thirteen long-term care (LTC) and assisted living facilities (ALF). Participants: Residents from LTC or ALF settings who ( a) received warfarin or direct-acting oral anticoagulants (DOACs) and ( b) residents with a valid indication for oral anticoagulants such as atrial fibrillation, venous thromboembolism, but were not receiving these drugs. Primary Outcome: Time in therapeutic international normalized ratio (INR) range (TTR). Results: A total of 563 residents (70% female) with an average age of 85 years were identified. Participants had an average of 7.5 comorbidities and 9 medications. A total of 391 (69%) residents with indications for OACs were receiving such medications. Indications were atrial fibrillation (63%), venous or pulmonary embolism (16%), cardiac valves (0.4%); 26% did not have documented indications. Warfarin and DOACs were prescribed for 213 (38%) and 178 (32%) respectively, and 172 (31%) received no OACs The TTR ranged from 56%-75% (mean 63%). The frequency of INR determinations ranged from every 7 to 20 days, (mean 13 days) with no apparent relationship between frequency of testing and TTR. Conclusion: The TTR was higher (63.8%) than literature average (50%), but remains suboptimal given expected benefits of TTRs >75% versus TTRs circa 60%. Documentation of indications for OACs needs improvement, and it is possible that OACs are underused. Further work is necessary to understand how OAC use may be optimized in these facilities.

Low Use of Oral Anticoagulant Prescribing for Secondary Stroke Prevention: Results From the Ontario Stroke Registry

BACKGROUND

Oral anticoagulation reduces the risk of stroke in atrial fibrillation but is often underused.

OBJECTIVES

To identify factors associated with oral anticoagulant prescribing and adherence after stroke or transient ischemic attack (TIA).

RESEARCH DESIGN

Retrospective cohort study using linked Ontario Stroke Registry and prescription claims data.

SUBJECTS

Consecutive patients with atrial fibrillation and ischemic stroke/TIA admitted to 11 stroke centers in Ontario, Canada between 2003 and 2011.

MEASURES

We used modified Poisson regression models to determine predictors of anticoagulant prescribing and multiple logistic regression to determine predictors of 1-year adherence.

RESULTS

Of the 5781 patients in the study cohort, 4235 (73%) were prescribed oral anticoagulants at discharge. Older patients were less likely to receive anticoagulation [adjusted relative risk (aRR) for each additional year=0.997; 95% confidence interval (CI), 0.995-0.998], as were those with TIA compared with ischemic stroke (aRR=0.904; 95% CI, 0.865-0.945), prior gastrointestinal bleed (aRR=0.778; 95% CI, 0.693-0.873), dementia (aRR=0.912; 95% CI, 0.856-0.973), and those from a long-term care facility (aRR=0.810; 95% CI, 0.737-0.891). After limiting the sample to those without obvious contraindications to anticoagulation, age, dementia, and long-term care residence continued to be associated with lower prescription of oral anticoagulants. One-year adherence to therapy was similar across most patient groups.

CONCLUSIONS

Age, dementia, and long-term care residence are predictors of lower oral anticoagulant use for secondary stroke prevention and represent key target areas for quality improvement initiatives.

The Utilization of Antithrombotic Therapy in Older Patients in Aged Care Facilities With Atrial Fibrillation

Oral anticoagulants are essential drugs for the prevention of thromboembolic events in patients with atrial fibrillation (AF). Anticoagulants are, however, commonly withheld in older people due to the risk and fear of hemorrhage. Although the underutilization of anticoagulants in patients with AF has been demonstrated internationally, few studies have been conducted among aged care residents. The aim of this study was to determine the utilization of anticoagulants among people with AF residing in aged care facilities. We performed a non-experimental, retrospective analysis designed to evaluate antithrombotic usage in patients with AF in Australia residing in aged care facilities, using data collected by pharmacists while performing Residential Medication Management Reviews (RMMRs). The utilization of antithrombotic therapy and the appropriateness of therapy were determined based on the CHADS₂, CHA₂DS₂-VASc, and HAS-BLED risk stratification schemes in consideration of documented contraindications to treatment. Predictors of anticoagulant use were determined using multivariate logistic regression. A total of 1952 RMMR patients with AF were identified. Only 35.6% of eligible patients (CHADS₂ score ≥2 and no contraindications to anticoagulants) received an anticoagulant. As age increased, the likelihood of receiving an anticoagulant decreased and the likelihood of receiving an antiplatelet or no therapy increased. In patients at high risk of stroke (CHADS score ≥2), utilization of anticoagulants dropped by 19.7% when the HAS-BLED score increased from 2 to 3, suggesting that physicians placed a heavier weighting on bleeding risk rather than stroke risk. Prescribing of anticoagulants was influenced to a greater extent by bleeding risk than it was by the risk of stroke. Further research investigating whether the growing availability of direct oral anticoagulants influences practice in this patient population is needed.

Leveraging Real-World Evidence in Disease-Management Decision-Making with a Total Cost of Care Estimator

BACKGROUND

Health management is becoming increasingly complex, given a range of care options and the need to balance costs and quality. The ability to measure and understand drivers of costs is critical for healthcare organizations to effectively manage their patient populations. Healthcare decision makers can leverage real-world evidence to explore the value of disease-management interventions in shifting total cost trends.

OBJECTIVE

To develop a real-world, evidence-based estimator that examines the impact of disease-management interventions on the total cost of care (TCoC) for a patient population with nonvalvular atrial fibrillation (NVAF).

METHODS

Data were collected from a patient-level real-world evidence data set that uses the IMS PharMetrics Health Plan Claims Database. Pharmacy and medical claims for patients meeting the inclusion or exclusion criteria were combined in longitudinal cohorts with a 180-day preindex and 360-day follow-up period. Descriptive statistics, such as mean and median patient costs and event rates, were derived from a real-world evidence analysis and were used to populate the base-case estimates within the TCoC estimator, an exploratory economic model that was designed to estimate the potential impact of several disease-management activities on the TCoC for a patient population with NVAF. Using Microsoft Excel, the estimator is designed to compare current direct costs of medical care to projected costs by varying assumptions on the impact of disease-management activities and applying the associated changes in cost trends to the affected populations. Disease-management levers are derived from literature-based concepts affecting costs along the NVAF disease continuum. The use of the estimator supports analyses across 4 US geographic regions, age, cost types, and care settings during 1 year.

RESULTS

All patients included in the study were continuously enrolled in their health plan (within the IMS PharMetrics Health Plan Claims Database) between July 1, 2010, and June 30, 2012. Patients were included in the final analytic file and were indexed based on (1) the service date of the first claim within the selection window (December 28, 2010-July 11, 2011) with a diagnosis of NVAF, or (2) the service date of the second claim for an NVAF medication of interest during the same selection window. The model estimates the current trends in national benchmark data for a hypothetical health plan with 1 million covered lives. The annual total direct healthcare costs (allowable and patient out-of-pocket costs) of managing patients with NVAF in this hypothetical plan are estimated at $184,981,245 ($25,754 per patient, for 7183 patients). A potential 25% improvement from the base-case disease burden and disease management could translate into TCoC savings from reducing the excess costs related to hypertension (-5.3%) and supporting the use of an appropriate antithrombotic treatment that prevents ischemic stroke (-0.7%) and reduces bleeding events (-0.1%).

CONCLUSIONS

The use of the TCoC estimator supports population health management by providing real-world evidence benchmark data on NVAF disease burden and by quantifying the potential value of disease-management activities in shifting cost trends.

Risk scores and geriatric profile: can they really help us in anticoagulation decision making among older patients suffering from atrial fibrillation?

OBJECTIVES

Anticoagulation for the prevention of cardio-embolism is most frequently indicated but largely underused in frail older patients with atrial fibrillation (AF). This study aimed at identifying characteristics associated with anticoagulation underuse.

METHODS

A cross-sectional study of consecutive geriatric patients aged ≥75 years, with AF and clear anticoagulation indication (CHADS₂ [Congestive heart failure, Hypertension, Age >75, Diabetes mellitus, and prior Stroke or transient ischemic attack] ≥2) upon hospital admission. All patients benefited from a comprehensive geriatric assessment. Their risks of stroke and bleeding were predicted using CHADS₂ and HEMORR2HAGES (Hepatic or renal disease, Ethanol abuse, Malignancy, Older (age >75 years), Reduced platelet count or function, Rebleed risk, Hypertension (uncontrolled), Anemia, Genetic factors, Excessive fall risk, and Stroke) scores, respectively.

RESULTS

Anticoagulation underuse was observed in 384 (50%) of 773 geriatric patients with AF (median age 85 years; female 57%, cognitive disorder 33%, nursing home 20%). No geriatric characteristic was found to be associated with anticoagulation underuse. Conversely, anticoagulation underuse was markedly increased in the patients treated with aspirin (odds ratio [OR] [95% confidence interval]: 5.3 [3.8; 7.5]). Other independent predictors of anticoagulation underuse were ethanol abuse (OR: 4.0 [1.4; 13.3]) and age ≥90 years (OR: 2.0 [1.2; 3.4]). Anticoagulation underuse was not inferior in patients with a lower bleeding risk and/or a higher stroke risk and underuse was surprisingly not inferior either in the AF patients who had previously had a stroke.

CONCLUSION

Half of this geriatric population did not receive any anticoagulation despite a clear indication, regardless of their individual bleeding or stroke risks. Aspirin use is the main characteristic associated with anticoagulation underuse.