Use of anticoagulation in elderly patients with atrial fibrillation who are at risk for falls

Risk of falls and major bleeds in patients on oral anticoagulation therapy

BACKGROUND

The risk of falls is the most commonly cited reason for not providing oral anticoagulation, although the risk of bleeding associated with falls on oral anticoagulants is still debated. We aimed to evaluate whether patients on oral anticoagulation with high falls risk have an increased risk of major bleeding.

METHODS

We prospectively studied consecutive adult medical patients who were discharged on oral anticoagulants. The outcome was the time to a first major bleed within a 12-month follow-up period adjusted for age, sex, alcohol abuse, number of drugs, concomitant treatment with antiplatelet agents, and history of stroke or transient ischemic attack.

RESULTS

Among the 515 enrolled patients, 35 patients had a first major bleed during follow-up (incidence rate: 7.5 per 100 patient-years). Overall, 308 patients (59.8%) were at high risk of falls, and these patients had a nonsignificantly higher crude incidence rate of major bleeding than patients at low risk of falls (8.0 vs 6.8 per 100 patient-years, P=.64). In multivariate analysis, a high falls risk was not statistically significantly associated with the risk of a major bleed (hazard ratio 1.09; 95% confidence interval, 0.54-2.21). Overall, only 3 major bleeds occurred directly after a fall (incidence rate: 0.6 per 100 patient-years).

CONCLUSIONS

In this prospective cohort, patients on oral anticoagulants at high risk of falls did not have a significantly increased risk of major bleeds. These findings suggest that being at risk of falls is not a valid reason to avoid oral anticoagulants in medical patients.

Supporting Treatment decision making to Optimise the Prevention of STROKE in Atrial Fibrillation: the STOP STROKE in AF study. Protocol for a cluster randomised controlled trial

BACKGROUND

Suboptimal uptake of anticoagulation for stroke prevention in atrial fibrillation has persisted for over 20 years, despite high-level evidence demonstrating its effectiveness in reducing the risk of fatal and disabling stroke.

METHODS

The STOP STROKE in AF study is a national, cluster randomised controlled trial designed to improve the uptake of anticoagulation in primary care. General practitioners from around Australia enrolling in this 'distance education' program are mailed written educational materials, followed by an academic detailing session delivered via telephone by a medical peer, during which participants discuss patient de-identified cases. General practitioners are then randomised to receive written specialist feedback about the patient de-identified cases either before or after completing a three-month posttest audit. Specialist feedback is designed to provide participants with support and confidence to prescribe anticoagulation. The primary outcome is the proportion of patients with atrial fibrillation receiving oral anticoagulation at the time of the posttest audit.

DISCUSSION

The STOP STROKE in AF study aims to evaluate a feasible intervention via distance education to prevent avoidable stroke due to atrial fibrillation. It provides a systematic test of augmenting academic detailing with expert feedback about patient management.

A review of the safety of anticoagulants in older people using the medicines management pathway: weighing the benefits against the risks

Anticoagulant drugs maintain a high potential for adverse events due to their inherent risk of haemorrhage and/or complex pharmacology. In addition, compromising the safety of these agents is the context in which they are principally used; that is, in the long-term prevention of thromboembolic diseases in an older patient population. These challenges are especially pronounced in the prevention of stroke in older persons with atrial fibrillation (AF), where the need for thromboprophylaxis is paramount and in whom the arrhythmia is most prevalent, but where the target population is simultaneously at high risk of adverse drug events. Essentially, this translates to the use of high-risk therapies on an indefinite basis, in persons who have multiple comorbidities, use polypharmacy, and who may have age-related functional and cognitive decline, culminating in a higher potential for medication misadventure. For this reason, anticoagulants mandate extra pharmacovigilance, and therefore the aim of this review is to address some of the key safety considerations in the use of anticoagulant drugs (warfarin, dabigatran, rivaroxaban), spanning the initiation of therapy to its ongoing management. Using the Medication Management Pathway (MMP) as a framework, in this review we canvas and highlight specific developments in practical strategies to facilitate the safe use of anticoagulants (particularly warfarin) in 'at-risk' elderly patients including: comprehensive risk/benefit assessment using novel risk stratification tools; focused medicines review services; therapeutic drug monitoring services delivered in the primary care setting; and practical education strategies and resources targeting the older patient population. Until newer alternative anticoagulants become viable options for widespread use, clinicians will necessarily need to rely on specific resources and interventions to facilitate the safe use of currently available anticoagulants (i.e. warfarin) in 'at-risk' older people.

Atrial fibrillation, anticoagulation, fall risk, and outcomes in elderly patients

Atrial fibrillation (AF) affects 2.5 million patients in the United States. The incidence of this condition increases with age, such that approximately 5% of people > 65 years of age have AF. Because of the lack of organized atrial contraction and thrombus formation in the left atrium, patients with AF are at increased risk of stroke. The estimated risk of stroke among all AF patients is 5% per year. Among patients without mitral stenosis, there is a graded relationship of stroke risk with the number of CHADS₂ risk factors. Warfarin is the recommended treatment for embolic stroke prophylaxis in AF in intermediate- to high-risk patients. However, elderly patients who are deemed to be at risk of falls are often not started on warfarin therapy secondary to a perceived higher risk of bleeding complications. These risks have been evaluated, but conclusive data regarding the risk-benefit trade-off are elusive. This review summarizes available data on the use of warfarin in elderly patients with AF, focusing on the risk of bleeding, and will specifically address the utility of falls risk assessment in the decision to initiate warfarin therapy for AF.

Factors affecting adherence to guidelines for antithrombotic therapy in elderly patients with atrial fibrillation admitted to internal medicine wards

INTRODUCTION

Current guidelines for ischemic stroke prevention in atrial fibrillation or flutter (AFF) recommend Vitamin K antagonists (VKAs) for patients at high-intermediate risk and aspirin for those at intermediate-low risk. The cost-effectiveness of these treatments was demonstrated also in elderly patients. However, there are several reports that emphasize the underuse of pharmacological prophylaxis of cardio-embolism in patients with AFF in different health care settings.

AIMS

To evaluate the adherence to current guidelines on cardio-embolic prophylaxis in elderly (> 65 years old) patients admitted with an established diagnosis of AFF to the Italian internal medicine wards participating in REPOSI registry, a project on polypathologies/polytherapies stemming from the collaboration between the Italian Society of Internal Medicine and the Mario Negri Institute of Pharmacological Research; to investigate whether or not hospitalization had an impact on guidelines adherence; to test the role of possible modifiers of VKAs prescription.

METHODS

We retrospectively analyzed registry data collected from January to December 2008 and assessed the prevalence of patients with AFF at admission and the prevalence of risk factors for cardio-embolism. After stratifying the patients according to their CHADS(2) score the percentage of appropriateness of antithrombotic therapy prescription was evaluated both at admission and at discharge. Univariable and multivariable logistic regression models were employed to verify whether or not socio-demographic (age >80years, living alone) and clinical features (previous or recent bleeding, cranio-facial trauma, cancer, dementia) modified the frequency and modalities of antithrombotic drugs prescription at admission and discharge.

RESULTS

Among the 1332 REPOSI patients, 247 were admitted with AFF. At admission, CHADS(2) score was ≥ 2 in 68.4% of patients, at discharge in 75.9%. Among patients with AFF 26.5% at admission and 32.8% at discharge were not on any antithrombotic therapy, and 43.7% at admission and 40.9% at discharge were not taking an appropriate therapy according to the CHADS(2) score. The higher the level of cardio-embolic risk the higher was the percentage of antiplatelet- but not of VKAs-treated patients. At admission or at discharge, both at univariable and at multivariable logistic regression, only an age >80 years and a diagnosis of cancer, previous or active, had a statistically significant negative effect on VKAs prescription. Moreover, only a positive history of bleeding events (past or present) was independently associated to no VKA prescription at discharge in patients who were on VKA therapy at admission. If heparin was considered as an appropriate therapy for patients with indication for VKAs, the percentage of patients admitted or discharged on appropriate therapy became respectively 43.7% and 53.4%.

CONCLUSION

Among elderly patients admitted with a diagnosis of AFF to internal medicine wards, an appropriate antithrombotic prophylaxis was taken by less than 50%, with an underuse of VKAs prescription independently of the level of cardio-embolic risk. Hospitalization did not improve the adherence to guidelines.

[Anticoagulation in the elderly]

The recommendations for anticoagulation in over 80 years old patients are based on the thromboembolic/bleeding risk relation. They add to the published recommendations for the specific indications. Low-molecular-weight heparin (LMWH) is used to prevent thromboembolism postoperatively. Compression stockings and/or intermittent pneumatic compression are used if bleeding risk is very high. The dose is increased starting at day two if the thromboembolic risk is very high. Bleeding and thromboembolic risks are re-evaluted daily. The antithrombotic therapy is adjusted accordingly. Prophylaxis of thromboembolism in patients with acute illnesses and bedrest is performed according postoperative care. Two-thirds of therapeutic doses of low-molecular-weight heparin are used to treat acute venous thromboembolism. Reduced renal function (creatinine clearance <30 ml/ min for most LMWHs or <20 ml/min for tinzaparin) should result in a further reduction of dose. Intensity and duration of prophylaxis of recurrent events with vitamin K antagonist or LMWH in malignancy follow current or herein described recommendations. Patients with atrial fibrillation are treated with vitamin K antagonists adjusted to an INR of 2-3 for prophylaxis of embolism. Further details of anticoagulant therapy should be in agreement with the national or international recommendations.

Prevention and management of stroke in very elderly patients

As the average human lifespan extends and medical care improves, there are more individuals above the age of 80 years who have a high quality of life. However, these very elderly individuals are particularly susceptible to stroke. Identifying ways to optimise the treatment and prevention of acute stroke in these much older people will increasingly be a priority for health-care providers, research funding agencies, and policy makers in years to come. Despite substantial advances in stroke research, with several therapeutic drugs being able to enhance clinical outcomes in people with stroke or who are at risk of stroke, the very elderly seem to receive fewer vascular protection interventions that have been shown to be effective in younger individuals. Although there has been an under-representation of the very elderly in studies of stroke therapy, these treatments might be of benefit to this group of patients. Indeed, emerging data indicate that the use of several of these therapies in routine clinical practice in the very elderly can be effective.