NOACs For Atrial Fib Anticoagulation May Have Lower Risk of Kidney Side Effects

Atrial Fibrillation - Wikipedia image

Normal rhythm tracing (top) Atrial fibrillation (bottom) Wikipedia

Interview with:
Dr Xiaoxi Yao PhD
Assistant Professor
Researcher
Mayo Clinic

What is the background for this study? What are the main findings?

Response: Lifelong oral anticoagulation, either with warfarin or a non-vitamin K antagonist oral anticoagulant (NOAC), is indicated for stroke prevention in most patients with atrial fibrillation (AF). Emerging evidence suggests that NOACs may be associated with better renal outcomes than warfarin.

The study found renal function decline is common among patients with atrial fibrillation treated with oral anticoagulants. NOACs, particularly dabigatran and rivaroxaban, may be associated with lower risks of adverse renal outcomes than warfarin.

Continue reading

Dementia Incidence Lower For Atrial Fibrillation Patients Treated With Anticoagulation

MedicalResearch.com Interview with:

Dr. Leif Friberg MD, PhD Associate professor in cardiology Karolinska Institute Friberg Resarch Stockholm, Sweden 

Dr. Leif Friberg

Dr. Leif Friberg MD, PhD
Associate professor in cardiology
Karolinska Institute
Friberg Resarch
Stockholm, Sweden 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: I have been doing research on atrial fibrillation and stroke risk for many years and knew that the very common heart arrhythmia is associated with a 40% increased risk of dementia. Considering that that 12-15% of 75 years olds have this arrhythmia, and even more at higher ages, the problem is significant to say the least.

The mechanism behind stroke in atrial fibrillation is that blood clots are formed in the heart. When these are dislodged they travel with the blood stream and may get stuck in the narrow vessels of the brain where they stop blood flow causing brain infarction or stroke. Oral anticoagulant drugs like warfarin or the newer so called NOAC (new oral anticoagulant) drugs are highly efficient in preventing formation of these large blood clots and offer at least 70% risk reduction. Now, blood clots come in different sizes. There are also microscopic clots that do not cause symptoms of stroke but all the same eat away at the brain at a slow but steady pace. Imaging studies shows this after only a few months or even weeks of atrial fibrillation. Our hypothesis was therefore: If anticoagulants are so effective in protecting against large clots, will they not help against the small ones too?

Continue reading

In Euthyroid Individuals, Higher Free Thyroid Levels Linked To Greater Risk of Atrial Fibrillation

MedicalResearch.com Interview with:
Christine Baumgartner MD
Inselspital
Universitätsspital Bern
Bern, Switzerland
Research Fellow, Division of Hospital Medicine
UCSF

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Overt and subclinical hyperthyroidism increase the risk of atrial fibrillation, but it is unclear whether subclinical hypothyroidism, which is known to increase cardiovascular events, or thyroid function in the normal range are also associated with incident atrial fibrillation. Given the high prevalence of atrial fibrillation and its associated morbidity and mortality, identifying potentially modifiable risk factors is important. Therefore, we aimed to assess the risk of atrial fibrillation in individuals with subclinical hypothyroidism or variations of thyroid function within the normal range.

Our main findings are that higher free thyroxine levels are associated with an increased risk of atrial fibrillation in euthyroid individuals, but thyroid-stimulating hormone levels within the euthyroid or subclinical hypothyroid range was not related to atrial fibrillation risk.

Continue reading

Life Simple 7 Score Closely Link To Risk of Atrial Fibrillation

MedicalResearch.com Interview with:

Parveen K. Garg, MD, MPH Assistant Professor of Clinical Medicine Keck Hospital of USC 

Dr. Garg

Parveen K. Garg, MD, MPH
Assistant Professor of Clinical Medicine
Keck Hospital of USC 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Atrial fibrillation is the most commonly presenting cardiac arrhythmia in clinical practice, affecting over 2 million people in the United States. This arrhythmia accounts for up to 15% of all strokes and annual costs for AF treatment are estimated at over 6.5 billion dollars. Despite the growing public health challenge that AF poses, effective prevention strategies are lacking. In 2010, the American Heart Association identified metrics of ideal cardiovascular health known as Life’s Simple 7 to target for the primary prevention of cardiovascular disease. We wanted to determine whether adherence to these health metrics helps prevent atrial fibrillation as well.

Therefore, we examined the association between the Life’s Simple 7 (LS7) and incident atrial fibrillation in the REasons for Geographic And Ethnic Differences in Stroke (REGARDS) study. We found that individuals in this study with optimal cardiovascular health (high adherence to LS7 metrics) had an over 30% lower risk of developing atrial fibrillation compared to those with inadequate cardiovascular health (low adherence to LS7 metrics). We also observed that even minor improvements in adherence to the LS7 (increase in total score by 1-point) were associated with a 5% lower risk of atrial fibrillation.

Continue reading

Study Finds Ablation To Be Superior For Atrial Fibrillation In Patients With Heart Failure

MedicalResearch.com Interview with:

Nassir F. Marrouche, MD Professor, Internal Medicine Cardiology University of Utah

Dr. Marrouche

Nassir F. Marrouche, MD
Professor, Internal Medicine
Cardiology
University of Utah 

MedicalResearch.com: What is the background for this study?

Response: Study the effectiveness of catheter ablation of Atrial Fibrillation in patients with heart failure in improving hard primary endpoints of mortality and heart failure progression when compared to conventional standard treatment

Continue reading

Morbidity and Financial Costs of Atrial Fibrillation High and Likely to Grow

MedicalResearch.com Interview with:

Sandra L. Jackson, PhD National Center for Chronic Disease Prevention and Health Promotion Centers for Disease Control and Prevention Chamblee GA

Dr. Sandra  Jackson

Sandra L. Jackson, PhD
National Center for Chronic Disease Prevention and Health Promotion
Centers for Disease Control and Prevention
Chamblee GA

MedicalResearch.com: What is the background for this study?

Response: People who have atrial fibrillation are at increased risk for having a heart attack or stroke. While we know that the percentage of the population with atrial fibrillation is increasing in the US, there is no national surveillance system to track the burden of emergency department visits, hospitalizations and deaths related to atrial fibrillation across all ages and health insurance provider types. This study combined data from the Healthcare Cost and Utilization Project and the National Vital Statistics System to provide national estimates for atrial fibrillation-related healthcare service use and deaths from 2006-2014.

Continue reading

Insertable Cardiac Monitors Detect Previously Undiagnosed Atrial Fibrillation

MedicalResearch.com Interview with:
James A. Reiffel, M.D
Professor Emeritus of Medicine
Special Lecturer in Medicine
Dept of Medicine Cardiology
Columbia University Medical Center

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Atrial fibrillation is a common arrhythmia (multi-millions of Americans) and carries with it a risk of stroke and of heart failure (among others) if not treated preventively. In many people, atrial fibrillation comes to attention because of symptoms, but not in all. The chances of developing Atrial fibrillation are substantially increased in certain populations of patients, such as the ones we enrolled in our study.  Continuous monitoring of such patients, as we did, and as others have also done recently, though in smaller numbers of patients, can detect otherwise unsuspected atrial fibrillation, which can lead to treatment before complications arise.

We found that using such monitoring, when monitored for 18 months, almost 1 in 3 patients had atrial fibrillation detected, as did 40% by 30 months. Intermittent monitoring, including by cell phones, may detect some atrial fibrillation but it is not nearly as effective as the type of monitoring we did and so many patients will be missed by lesser monitoring methods.

Continue reading

Contraindications Not The Reason Atrial Fibrillation Patients Not Prescribed Anticoagulants

MedicalResearch.com Interview with:

Tom Marshall, MSc, PhD, MRGP, FFPH Professor of public health and primary care Institute of Applied Health Research University of Birmingham Birmingham UK

Prof. Marshall

Tom Marshall, MSc, PhD, MRGP, FFPH
Professor of public health and primary care
Institute of Applied Health Research
University of Birmingham
Birmingham UK 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: It is widely recognised that anticoagulants are underused in patients with atrial fibrillation (AF) although they are effective in reducing risk of stroke. We investigated whether this could be explained by the fact that many AF patients have conditions which are considered relative contraindications to their use.

We analysed electronic medical records from 645 general practices from 2004 to 2015 and included over 1 million patients with AF. We found that about 6% of AF patients had are relative contraindications such as recent history of major bleeding. In each of the 12 years, similar numbers of patients with and without contraindications were prescribed anticoagulants.

Continue reading

Patients With Paroxysmal Atrial Fibrillation Less Likely To Receive Anticoagulants

MedicalResearch.com Interview with:

Dr Nicola Adderley BA, MSci (Cantab), MA, MPhil, PhD Institute of Applied Health Research Research Fellow University of Birmingham

Dr. Adderley

Dr Nicola Adderley BA, MSci (Cantab), MA, MPhil, PhD
Institute of Applied Health Research
Research Fellow
University of Birmingham

MedicalResearch.com: What is the background for this study?

Response: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and a major global public health problem. It is associated with a five-fold increase in risk of stroke.

There are three types of AF – paroxysmal, persistent or permanent. In paroxysmal AF, episodes come and go, and usually stop without any treatment. With persistent AF episodes can last for periods of more than seven days and are treated with medication or a medical procedure called cardioversion. In permanent AF, the irregular heartbeat is present all the time and cardioversion has failed to restore a normal heart rhythm.

All patients with AF, including paroxysmal AF, are at an increased risk of stroke. UK guidelines recommend anticoagulant treatment, such as the blood-thinning drug warfarin, for patients with all types of AF in order to reduce the risk of stroke.

Our study aimed to determine whether patients with paroxysmal AF are less likely to be treated with anticoagulants than patients with persistent or permanent AF and to investigate trends in treatment between 2000 and 2015.

Continue reading

Normalizing Testosterone With Replacement Therapy Reduced Atrial Fibrillation Risk

MedicalResearch.com Interview with:

Rajat S. Barua, MD; PhD; FACC; FSCAI Associate Professor of Medicine (Cardiology), University of Kansas School of Medicine Director, Cardiovascular Research, Dept. of Cardiology, Kansas City VA Medical Center Director, Interventional Cardiology & Cardiac Catheterization Laboratory Kansas City VA Medical Center

Dr. Barua

Rajat S. Barua, MD; PhD; FACC; FSCAI
Associate Professor of Medicine (Cardiology), University of Kansas School of Medicine
Director, Cardiovascular Research, Dept. of Cardiology, Kansas City VA Medical Center
Director, Interventional Cardiology & Cardiac Catheterization Laboratory
Kansas City VA Medical Center

MedicalResearch.com: What is the background for this study?

Response: Atrial fibrillation is the most common cardiac arrhythmia worldwide, with significant morbidity, mortality and financial burden. Atrial fibrillation is known to increase with age and is higher in men than in women. Although the underlying mechanisms of this sex difference are still unclear, one preclinical and several small clinical studies have suggested that testosterone deficiency may play a role in the development of atrial fibrillation. To date, no studies have investigated the effect of testosterone-level normalization on incidence of new atrial fibrillation in men after testosterone replacement therapy.

In this study, we investigated the incidence of atrial fibrillation in hypogonadal men with documented low testosterone levels. We compared the incidence of atrial fibrillation among patients who did not receive any testosterone replacement therapy, those who received testosterone replacement therapy that resulted in normalization of total testosterone, and those who received testosterone replacement therapy but that did not result in normal total testosterone levels.

Continue reading

Biomarker VCAM-1 Associated With New Onset Atrial Fibrillation

MedicalResearch.com Interview with:
Stefan Kiechl, MD and
Karin Willeit, MD
Department of Neurology
Medical University Innsbruck
Innsbruck, Austria 

MedicalResearch.com: What is the background for this study?

Response: Atrial fibrillation (AF) is the most common cardiac arrhythmia and a major contributor to thromboembolic stroke and population morbidity and mortality. Aside from well-established risk factors such as age, heart failure, and hypertension, inflammation has been suggested to play a significant role in the pathogenesis of AF. This is evidenced by histologic studies that found marked inflammatory infiltrates in atrial biopsies of AF patients and by epidemiological studies demonstrating an association of circulatory inflammation markers with incident AF. Of note, an increased endocardial expression of vascular intercellular adhesion molecule 1 (VCAM-1), a mediator of leukocyte trafficking, during rapid atrial pacing was demonstrated which was shown to contribute to an inflammatory and prothrombotic environment within atrial tissue.

Because it is still unclear whether inflammation related to AF is primarily a systemic or localized phenomenon, we sought to examine the association of 13 baseline inflammation markers with incident atrial fibrillation in the prospective population-based Bruneck Study and to replicate key findings in a second cohort, the SAPHIR Study.

Continue reading

Valvular Heart Disease: Edoxaban vs Warfarin in the ENGAGE AF-TIMI 48 Trial

MedicalResearch.com Interview with:
Raffaele De Caterina MD, PhD

Professor of Cardiology and Director of the University Cardiology Division
‘G d’Annunzio’ University in Chieti

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: The widely used term “valvular atrial fibrillation” encompasses a variety of conditions in which atrial fibrillation and valvular heart disease coexist. Since most trials of the non-vitamin K antagonist oral anticoagulants (NOACs) have variably excluded “valvular atrial fibrillation”, in more or less restrictive terms, there has been uncertainty whether NOACs can be used in such varied conditions. While atrial fibrillation in the presence of a mechanical valve or rheumatic mitral stenosis has to be a true contraindication (unfavorable data with one NOAC in the former setting; no data in the latter setting), patients with valvular diseases such as mitral insufficiency, aortic stenosis, aortic insufficiency, or with the presence of a bioprosthesis, have been variably included in the phase III trials of NOACs, but had not been extensively and conclusively studied before.

Continue reading

Does Stress Raise Risk of Atrial Fibrillation?

MedicalResearch.com Interview with:

Simon Graff MD Department of Public Health Research Unit for General Practice Aarhus University Aarhus C, Denmark

Dr. Simon Graff

Simon Graff MD
Department of Public Health
Research Unit for General Practice
Aarhus University
Aarhus C, Denmark 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: The presented study is a continuation of our interest in the role of stress and the possible causes of atrial fibrillation.  We published a study that showed that spousal bereavement were followed by a transiently increased risk of new onset of atrial fibrillation. With spousal bereavement being one of the most stressful life-event, we wanted to know whether minor and differentiated stress exposures had an effect as well. Therefore we used register based data on perceived stress as a new measure of exposure.

Continue reading

Appropriate Anticoagulation Underutilized in Atrial fibrillation

MedicalResearch.com Interview with:
Dr. Ying Xian
 MD PhD
Department of Neurology,
Duke Clinical Research Institute
Duke University Medical Center
Durham, North Carolina

MedicalResearch.com: What is the background for this study?

Response: Atrial fibrillation (AF) is the most common arrhythmia. AF increases the risk for stroke and accounts for 10% to 15% of all ischemic strokes. While the burden of AF-related stroke is high, AF is a potentially treatable risk factor. Numerous studies have demonstrated that vitamin K antagonists, such as warfarin, or non-vitamin K antagonist oral anticoagulants (NOACs), reduce the risk of ischemic stroke. Based on these data, current guidelines recommend adjusted-dose warfarin or NOACs over aspirin for stroke prevention in high-risk patients with Atrial fibrillation.

Continue reading

Stopping Warfarin in Dementia Patients with Atrial Fib Associated With Increased Risk of Stroke and Death

MedicalResearch.com Interview with:

Ariela Orkaby, MD, MPH Geriatrics & Preventive Cardiology Associate Epidemiologist Division of Aging, Brigham and Women's Hospital Instructor in Medicine, Harvard Medical School

Dr. Ariela Orkaby

Ariela Orkaby, MD, MPH
Geriatrics & Preventive Cardiology
Associate Epidemiologist
Division of Aging, Brigham and Women’s Hospital
Instructor in Medicine, Harvard Medical School

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Atrial Fibrillation is a common heart rhythm that affects 1 in 25 adults over age 60 and 1 in 10 adults over age 80. The feared consequence of atrial fibrillation is stroke, leading to the prescription of blood thinning medications (anticoagulants such as warfarin) to prevent strokes. However, there is an underutilization of these life-saving medications in older adults, and particularly in those who have dementia. In part, this is due to a lack of research and inclusion of older adults with dementia in prior studies.

In this study, we used clinical Veterans Administration data, linked to Medicare, to follow 2,572 individuals over age 65 who had atrial fibrillation and until a diagnosis of dementia. The average age was 80 years, and 99% were male. We found that only 16% remained on warfarin. We used statistical methods to account for reasons why a patient would or would not be treated with warfarin and found that those who continued to take warfarin had a significantly lower risk of stroke (HR 0.74, 95% Confidence interval 0.54- 0.99, p=0.47) and death (HR 0.72, 95% CI 0.60-0.87, p<0.01) compared to those who did not continue to take warfarin, without an increased risk of bleeding.

Continue reading

Increase In Subdural Hematomas Associated With Increase Use of Antithrombotic Drugs


MedicalResearch.com Interview with:

David Gaist, MD, PhD</strong> Department of Neurology Odense University Hospital University of Southern Denmark Odense, Denmark

Dr. David Gaist

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: The incidence of subdural hematoma (SDH; a bleed located within the skull, but outside the brain) has been reported to be on the increase. Previous studies have shown an association between use of antithrombotic drugs and SDH. However, studies with updated estimates of this risk and with focus on current more complex and aggressive regimens of antithrombotic treatment are scarce.

We therefore performed this study, where we identified 10,010 patients aged 20-89 years that were admitted with SDH in Denmark in 2000 through 2015. Preadmission use of antithrombotic drugs (low-dose aspirin, clopidogrel, vitamin K antagonist, e.g. warfarin, and direct oral anticoagulants) of these cases was compared to that of 400,380 individuals from the general population with no history of SDH (controls).

We found that use of antithrombotic drugs was associated with an increased risk of subdural hematoma . The magnitude of this risk varied by type of antithrombotic, and was, e.g., low for use of low-dose aspirin, and highest for warfarin. Further, with a single exception (low-dose aspirin and dipyridamole), concurrent use of more than one antithrombotic drug was associated with higher risk of SDH, particularly if warfarin was taken along with an antiplatelet drug, e.g., low-dose aspirin or clopidogrel. Increasing use of antithrombotic drugs was observed in the study period. The incidence of subdural hematomas in the Danish population also increased markedly in the years 2000-2015, particularly among those aged 75+ years. Our study indicates that this increased incidence, can, at least partly, be explained by increased use of antithrombotic drugs.

Continue reading

Which AFib Patients Should Resume Warfarin After Intracranial Hemorrhage?

MedicalResearch.com Interview with:
Peter Brønnum Nielsen MD PhD
Aalborg Thrombosis Research Unit
Department of Clinical Medicine
Faculty of Health
Department of Cardiology, Atrial Fibrillation Study Group
Aalborg University Hospital
Aalborg, Denmark
 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response:   Patients who sustain an intracranial hemorrhage (ICH) event are often excluded from randomized trials investigating stroke prevention in atrial fibrillation (AF) by use of oral anticoagulant treatment.

Continue reading

Variable Effects of Vitamin C on Post-Operative Atrial Fibrillation

MedicalResearch.com Interview with:

Dr-Harri-Hemilae.jpg

Dr. Harri Hemilae

Harri Hemilä, MD, PhD
Department of Public Health
University of Helsinki

MedicalResearch.com: What is the background for this study?

Response: I have a long term interest in vitamin C. Previously I have shown that it alleviates exercise-induced bronchoconstriction (EIB) (http://dx.doi.org/10.1186/1710-1492-10-58 ) and shortens the duration of colds ( http://dx.doi.org/10.1371/journal.pmed.0020168 ). Now I had been following the literature and I noted that a number of randomized trials were being published about vitamin C for preventing post-operative atrial fibrillation (POAF). Therefore I reasoned that it is worthwhile to analyze that set of trials

Continue reading

AFib Ablation Generally Successful But Not Exempt from Complication Risk

MedicalResearch.com Interview with:

Dr. Elena Arbelo MD PhD Department of Cardiology, Cardiovascular Institute Hospital Clínic de Barcelona. University of Barcelona Barcelona, Spain

Dr. Elena Arbelo

Dr. Elena Arbelo MD PhD
Department of Cardiology, Cardiovascular Institute
Hospital Clínic de Barcelona
University of Barcelona
Barcelona, Spain

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Almost 20 years after its first description, catheter ablation is a widely-used treatment strategy for patients with symptomatic atrial fibrillation (AF) (AFib) resistant to antiarrhythmic drugs (AAD).

If we look at the results of the ESC Pilot Atrial Fibrillation General Registry1, which included about 3000 consecutive in- and outpatients with AF presenting to cardiologists in nine participating countries in Europe, catheter ablation had previously attempted 7.6% overall, most often in those with paroxysmal AF (15.6%). A further 7.8% were prescribed an ablation as part of their management, which went up to a 19.3% in the case of paroxysmal AFib.

On the other hand, several randomised clinical trials (RCTs) have shown better results of AFib ablation compared to antiarrhythmic drugs (AADs)2-6. However, these studies had a rather small sample size of selected patients, and interventions were undertaken by experienced operators with clearly pre-specified protocols. With rising prevalence of AFib and increasingly available treatment options, it was of utmost importance to have an accurate picture of contemporary AFib ablation and its outcomes which will allow the identification of practice gaps and assist evidence-based guidelines for the management of these patients.

Continue reading

More Than Moderate Alcohol Not Good For The Heart

MedicalResearch.com Interview with:

Gregory M Marcus, MD, MAS, FACC, FAHA, FHRS Director of Clinical Research Division of Cardiology Endowed Professor of Atrial Fibrillation Research University of California, San Francisco

Dr. Gregory M Marcus

Gregory M Marcus, MD, MAS, FACC, FAHA, FHRS
Director of Clinical Research
Division of Cardiology
Endowed Professor of Atrial Fibrillation Research
University of California, San Francisco

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Moderate alcohol consumption has previously been associated with a decreased risk of heart attack. However, as we have previously shown that individuals who believe alcohol to be good for the heart tend to drink more, there is a concern that these previous data might appear to justify excessive alcohol consumption.

In addition, previous research on the topic of alcohol consumption and heart disease has relied almost entirely on participant self-report, which is known to be particularly unreliable among heavy drinkers. Finally, previous research has sought to study relationships between alcohol and various types of heart disease, but there has not been an emphasis on individual-level characteristics that might influence these relationships.
Continue reading

Predicting Unsuccessful Electrical Cardioversion for Acute Atrial Fibrillation

MedicalResearch.com Interview with:
Juhani Airaksinen, MD, PhD

Professor, Chief of Cardiology
Directork Heart Center
Turku University Hospital

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Electrical cardioversion (ECV) is an essential part of rhythm control strategy in patients with paroxysmal atrial fibrillation (AF). There is limited information on unsuccessful outcome of ECV (i.e. failure of cardioversion or early recurrence of AF) for acute AF. Our study shows that the risk of unsuccessful outcome of ECV can be predicted using five simple clinical variables. These variables were used to derivate and validate a novel risk stratification tool (the AF-CVS Score) for predicting unsuccessful ECV outcome. Study patients with high AF-CVS Score points (>5) had a high incidence of ECV failure or early AF recurrence.

Continue reading

Association Between Statin Use and Ischemic Stroke or Hemorrhage in Patients Taking Dabigatran for A Fib

MedicalResearch.com Interview with:

Dr-Tony-Antoniou.jpg

Dr. Tony Antoniou

Dr. Tony Antoniou, PhD Research Scholar
Department of Family and Community Medicine and a Scientist
Keenan Research Centre of the Li Ka Shing Knowledge Institute
St. Michael’s Hospital
Assistant Professor in the Department of Family and Community Medicine and
Leslie Dan Faculty of Pharmacy
University of Toronto, Toronto, Ontario

MedicalResearch.com: What is the background for this study?
What are the main findings?

Response: Dabigatran etexilate is an anticoagulant that is commonly used for stroke prevention in patients with atrial fibrillation. Absorption of dabigatran etexilate is opposed by intestinal P-glycoprotein, an efflux transporter. Once absorbed, dabigatran etexilate is converted to its active form by carboxylesterase enzymes. Unlike other statins, simvastatin and lovastatin can inhibit P-glycoprotein and carboxylesterase. This may result in increased absorption of dabigatran etexilate, thereby increasing the risk of bleeding. Conversely, inhibition of carboxylesterase may decrease the effectiveness of dabigatran etexilate.

Continue reading

Smartphone App Can Screen For Atrial Fibrillation

MedicalResearch.com Interview with:

Dr. Ngai-yin Chan Princess Margaret Hospital Lai Chi Kok, Hong Kong

Dr. Ngai-yin Chan

Dr. Ngai-yin Chan
Princess Margaret Hospital
Lai Chi Kok, Hong Kong

MedicalResearch.com: What is the background for this study?

Response: Atrial fibrillation (AF) is the most common sustained heart rhythm disorder which can cause stroke, heart failure and an increased risk of death. The risk of stroke can be reduced substantially with drug treatment. However, a quarter of patients with AF causing stroke have silent and asymptomatic AF before stroke. The current guidelines recommend opportunistic screening for AF. Whether systematic community screening for AF with a convenient smartphone ECG can reduce the burden of AF remains unknown. Continue reading

Effectiveness and Safety of Dabigatran, Rivaroxaban, and Apixaban Versus Warfarin in Nonvalvular Atrial Fibrillation

MedicalResearch.com Interview with:

Xiaoxi Yao, PhD, MPH, MS Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery Mayo Clinic Rochester, MN

Dr. Xiaoxi Yao

Xiaoxi Yao, PhD, MPH, MS
Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery
Mayo Clinic
Rochester, MN

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Atrial fibrillation (AF) is the most common arrhythmia requiring treatment, affecting 3-6 million Americans. AF is associated with a 5 fold risk of stroke, which can be substantially reduced by oral anticoagulants. For over a half century, warfarin was the only option for long-term oral anticoagulation in the U.S., but the use of warfarin can be cumbersome. Warfarin has numerous interactions with food and other drugs, and requires regular lab testing and dose adjustment. Since 2010, four non–vitamin K antagonist oral anticoagulants (NOACs) have been approved by the FDA. In comparison to warfarin, the fixed-dosage NOACs provide more convenient therapeutic options and demonstrated at least equivalent efficacy and safety in large phase III clinical trials. However, the outcomes achieved in idealized clinical trial settings may not necessarily translate to routine clinical practice.

In this large cohort of patients with nonvalvular AF, we assessed the real-world effectiveness and safety of three NOACs (dabigatran, rivaroxaban, and apixaban), comparing each agent with warfarin. We found apixaban was associated with lower risks of both stroke and major bleeding, dabigatran was associated with similar risk of stroke but lower risk of major bleeding, and rivaroxaban was associated with similar risks of both stroke and major bleeding in comparison to warfarin.

Continue reading

The GLORIA-AF Registry: Two Year Follow Up of Dabigatran for Non-Valvular A Fib Reported

MedicalResearch.com Interview with:

Menno Huisman, MD, PhD Associate professor Department of Medicine Leiden University Medical Center The Netherlands

Dr. Menno Huisman

Menno Huisman, MD, PhD
Associate professor
Department of Medicine
Leiden University Medical Center
The Netherlands

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: GLORIA™-AF is one of the largest ongoing global registry programs examining the use of oral antithrombotic agents in real-world clinical practice. The program is designed to characterize the population of newly diagnosed patients with non-valvular atrial fibrillation (NVAF) at risk for stroke, and to study patterns, predictors and outcomes of different regimens for stroke prevention.

At the ESC Congress 2016, we presented the first Phase II results of GLORIA-AF from approximately 3,000 NVAF patients, which showed that treatment with PRADAXA was associated with low incidences of stroke, major bleeding and life threatening bleeding. Less than 1% of PRADAXA-treated patients experienced a stroke over two years (0.63%). Major bleeding occurred in 1.12% of PRADAXA-treated patients and 0.54% experienced a life-threatening bleed.

Continue reading

Atrial Fibrillation Associated With Wide Range of Cardiovascular Events

MedicalResearch.com Interview with:
Ayodele Odutayo, DPhil student
Centre for Statistics in Medicine
Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences
University of Oxford, Oxford, UK

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Atrial fibrillation is associated with an increased risk of all cause mortality and stroke, as well as higher medical costs and a reduced quality of life. The association between atrial fibrillation and cardiovascular outcomes other than stroke is less clear.

We found that atrial fibrillation is associated with a wide range of cardiovascular events, including cardiovascular mortality, major cardiovascular events, heart failure, ischaemic heart disease, chronic kidney disease, and sudden cardiac death, as well as stroke and all cause mortality. The relative and absolute risk increase associated with many of these events is greater than that of stroke. Interventions are needed to reduce the risk of non-stroke cardiovascular outcomes in adults with atrial fibrillation.

Continue reading

Adding Black Race To Scoring System Improves Stroke Prediction in AFib

MedicalResearch.com Interview with:

Dr. Mary Vaughan Sarrazin PhD Associate Professor Department of Internal Medicine University of Iowa Roy and Lucille Carver College of Medicine, and Iowa City VA Medical Center, Center for Comprehensive Access & Delivery Research and Evaluation (CADRE) Iowa City

Dr. Mary Vaughan Sarrazin

Dr. Mary Vaughan Sarrazin PhD
Associate Professor
Department of Internal Medicine
University of Iowa Roy and Lucille Carver College of Medicine, and
Iowa City VA Medical Center, Center for Comprehensive Access & Delivery
Research and Evaluation (CADRE)
Iowa City

MedicalResearch.com: What is the background for this study?

Response: Atrial fibrillation is associated with a higher risk of stroke. The CHA2DS2VASc score (congestive heart failure, hypertension, age 75 or older, diabetes, previous stroke, vascular disease, age 65-74, female sex) reflects stroke risk and is used to guide decisions regarding anticoagulation. Our prior work suggests that African Americans have a higher risk of stroke compared to other patients with atrial fibrillation, even after risk factor adjustments. In the current study, we used Medicare data to test whether addition of black race to CHA2DS2VASc score improves stroke prediction in patients with atrial fibrillation.

Continue reading

Selection Bias Does Not Explain White Prevalence of Prevalence of Atrial Fibrillation

MedicalResearch.com Interview with:

Evan L. Thacker, PhD. Brigham Young University Provo, UT

Dr. Evan Thacker

Evan L. Thacker, PhD.
Assistant Professor
College of Life Sciences
Brigham Young University
Provo, UT

MedicalResearch.com: What is the background for this study?

Response: Atrial fibrillation (AF) is diagnosed more commonly in whites than blacks in the United States. This seems paradoxical because blacks have higher prevalence of many risk factors for AF. Various explanations for this paradox have been proposed, including biological explanations as well as potential biases in research studies. We investigated one such bias – selection bias – as a potential explanation for the paradox. We did this by comparing the racial difference in atrial fibrillation prevalence among people who enrolled in an epidemiologic study versus people who were eligible to enroll in the study but did not enroll.

Continue reading

Atrial Fibrillation Associated With Increased of Risk of Cancer in Women

MedicalResearch.com Interview with:
David Conen MD MPH
Department of Medicine
University Hospital Basel
Basel Switzerland

MedicalResearch.com: What is the background for this study? What are the main findings?

Dr. Conen: A previous study of a contemporary population with atrial fibrillation (AF) treated with oral anticoagulation showed that over a third of all deaths were due to non-cardiovascular causes, and malignancies accounted for the largest proportion of these deaths. These data suggested that AF patients may have an increased risk of malignancies, but little data existed to support this hypothesis.

During more than 19 years of follow-up, our study showed that atrial fibrillation was a significant risk factor for the occurrence of malignant cancer. After taking into account a large number of other risk factors and co-morbidities, the risk of cancer was approximately 50% higher among women with new-onset AF compared to women without AF. The risk of cancer was highest in the first 3 months after new-onset AF but remained significant beyond 1 year after new-onset AF (adjusted HR 1.42, p<0.001). We also observed a trend towards an increased risk of cancer mortality among women with new-onset AF.

Continue reading

Even on Anticoagulation Atrial Fibrillation Contributes to Dementia Risk

MedicalResearch.com Interview with:

T. Jared Bunch, MD Director of Heart Rhythm Research Medical Director for Heart Rhythm Services Intermountain Healthcare system

Dr. T. Jared Bunch

T. Jared Bunch, MD
Director of Heart Rhythm Research
Medical Director for Heart Rhythm Services
Intermountain Healthcare System

MedicalResearch.com: What is the background for this study? What are the main findings?

Dr. Bunch: Approximately 6 years ago we found that patients with atrial fibrillation experienced higher rates of all forms of dementia, including Alzheimers disease.  At the time we started to ask the questions of why this association existed.  We know that atrial fibrillation patients experience higher rates of stroke.  These patients are placed on blood thinners, most commonly warfarin, to lower risk of stroke which at the same time expose that patient to a higher risk of intracranial bleeding.  One possibility to explain the association was that perhaps dementia in the manifestation of many small clots or bleeds in the brain that in total lead to cognitive decline.  If this is the case, then the efficacy and use of anticoagulation is very important in atrial fibrillation patients.

We conducted additional studies that showed this to be the case.  In patients with no history of dementia, managed long-term with warfarin anticoagulation, those that had levels that were frequently too higher or too low that resulted in poor times in therapeutic range, experienced significantly higher rates of dementia.  The risk was highest in younger atrial fibrillation patients that were less than 80 years of age.  We then found that in atrial fibrillation patients that were frequently over anticoagulated and also use an antiplatelet agent, aspirin or plavix, the dementia rates nearly doubled.  At this point we raised the question if atrial fibrillation increased the risk beyond anticoagulation, or does anticoagulation efficacy drive most of the risk.  This question formed the background of the current study.

Continue reading

Anticoagulants Remove Excess Stroke Risk Posed By Atrial Fibrillation

MedicalResearch.com Interview with:

Dr. Ben Freedman OAM Deputy Director Research Strategy, Heart Research Institute/Charles Perkins Centre Professor of Cardiology, Sydney Medical School Head Vascular Biology Anzac Research Institute Honorary VMO, Concord Repatriation General Hospital University of Sydney

Dr. Ben Freedman

Dr. Ben Freedman OAM 
Deputy Director Research Strategy, Heart Research Institute/Charles Perkins Centre
Professor of Cardiology, Sydney Medical School
Head Vascular Biology Anzac Research Institute
Honorary VMO, Concord Repatriation General Hospital
University of Sydney

MedicalResearch.com: What is the background for this study?

Dr. Freedman: Guidelines recommend that patients with atrial fibrillation (AF) at high enough risk for stroke should be treated with anticoagulant. Anticoagulant drugs are remarkably effective in reducing stroke risk by about two thirds, and death by between a quarter and a third. Unfortunately, strokes can still occur when patients are prescribed anticoagulant for Atrial Fibrillation, and it is often presumed this residual risk of stroke represents treatment failure, though there are few data about this important issue.

MedicalResearch.com: What are the main findings?

Dr. Freedman: We were able to compare the risk of stroke in a cohort of patients with AF commenced on anticoagulant, with a very large closely-matched cohort seen in general practice at the same time but without AF. This is a unique comparison. We found that the residual risk of stroke in such anticoagulant-treated patients was virtually identical to that in the matched control cohort. The implication is that the residual risk of stroke may not be treatment failure, but the risk of non-cardioembolic stroke in people of a similar age and stroke risk profile but without Atrial Fibrillation. The residual risk of death in those on anticoagulant was higher than the matched controls, and intermediate between the control rate and the mortality rate for untreated AF.

Continue reading

Atrial Fibrillation In Stroke Patients Deemed Underestimated

MedicalResearch.com Interview with:

Dr. Rolf Wachter Head Senior physician University of Goettingen Göttingen, Germany

Dr. Rolf Wachter

Dr. Rolf Wachter
Head Senior physician
University of Goettingen
Göttingen, Germany

Medical Research: What is the background for this study? What are the main findings?

Dr. Wachter: Atrial Fibrillation is a known risk factor for stroke, and in stroke patients, it is a strong predictor of adverse outcome, if it is not adequately treated (e.g. by anticoagulation). However, in its paroxysmal form, Atrial Fibrillation (AF) may escape routine diagnostics. We aimed to show that we can increase the number of patients with detected AF if we do more monitoring for atrial fibrillation. As a unique feature of our study, we did not focus on a certain stroke subtype (i.e. cryptogenic stroke), but we aimed to consider all patients >= 60 years in whom the detection of  Atrial Fibrillation has a clinical relevance.

The main finding of our study was that enhanced and prolonged Holter ECG monitoring (3×10 days of monitoring, analysed in a dedicated core lab) tripled the number of detected AF cases (from 4.5 to 13.5 %). 11 patients had to undergo enhanced and prolonged monitoring to find one additional case of Atrial Fibrillation.

Continue reading

Flu Infection Raises Risk of New Onset Atrial fibrillation

MedicalResearch.com Interview with:
Tze-Fan Chao MD PhD
Division of Cardiology, Department of Medicine
Taipei Veterans General Hospital
Institute of Clinical Medicine, and Cardiovascular Research Center
National Yang-Ming University, Taipei, Taiwan
Su-Jung Chen MD
Division of Infectious Diseases, Department of Medicine, Taipei Veterans General Hospital,
Institute of Public Health and School of Medicine, National Yang-Ming University
Taipei, Taiwan

MedicalResearch: What is the background for this study? What are the main findings?

Response: Atrial fibrillation (AF) is the most common cardiac arrhythmia in clinical practice, accounting for frequent hospitalizations, hemodynamic abnormalities, and thromboembolic events. Although the detailed mechanism of the occurrence of Atrial fibrillation remains unclear, systemic inflammation and sympathetic nervous system have been demonstrated to play an important role in the pathogenesis of AF. Flu (influenza infection) is a common disease which could happen to everyone in the daily life. It could cause significant morbidity and mortality, and is a serious human health concern worldwide. Previous studies have shown that influenza infection not only results in the productions of pro-inflammatory cytokines, but also activates the sympathetic nervous system, which are all related to the occurrence of  Atrial fibrillation. Therefore, we hypothesized that influenza infection could be a risk factor of new-onset AF. We also tested the hypothesis that influenza vaccination, a useful way to reduce the risk of influenza infection, could decrease the risk of AF.

In this large scale nationwide case-control study, a total of 11,374 patients with newly diagnosed  Atrial fibrillation were identified from the Taiwan National Health Insurance Research Database. On the same date of enrollment, 4 control patients (without AF) with matched age and sex were selected to be the control group for each study patient. The relationship between AF and influenza infection/vaccination 1 year before the enrollment was analyzed. The results showed that influenza infection was associated with an 18% increased risk of AF, and the risk could be easily reduced through influenza vaccination.

Continue reading

For Medicare Patients, Dabigatran Offers Significant Cost Savings Over Warfarin

Geoffrey Barnes, MD, MSc Clinical Lecturer Cardiovascular Medicine and Vascular Medicine University of Michigan Health System

Dr. Barnes

MedicalResearch.com Interview with:
Geoffrey Barnes, MD, MSc
Clinical Lecturer
Cardiovascular Medicine and Vascular Medicine
University of Michigan Health System

Medical Research: What is the background for this study?

Dr. Barnes: Although warfarin has been the primary anticoagulant used for stroke prevention in atrial fibrillation for over 60 years, four new direct oral anticoagulants (DOACs) have been introduced into the market since 2010. Dabigatran, which directly inhibits thrombin, was found to have better prevention of ischemic stroke and a significant reduction in hemorrhagic stroke (bleeding strokes) for patients with atrial fibrillation at intermediate and high risk of stroke.  Prior cost-effectiveness studies have shown that dabigatran is cost-effective from both the societal and payer (usually Medicare) perspectives.  However, none of those studies looked at the patient’s out-of-pocket costs and the impact of prescription drug coverage

Medical Research: What are the main findings?

Dr. Barnes: We found that patients with prescription drug coverage (Medicare Part D) had significant cost savings when choosing dabigatran over warfarin.  This is primarily because of the reduction in both types of stroke as well not needing to have frequent blood draws, as are required by warfarin.  However, when patients do not have prescription drug coverage, the costs for dabigatran are quite high.  Continue reading

Study Compares Anticoagulation Risk Scores in Atrial Fibrillation

H.A. (Hendrika) van den Ham PharmD Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Institute for Pharmaceutical Sciences Utrecht University The Netherlands.MedicalResearch.com Interview with:
H.A. (Hendrika) van den Ham PharmD

Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Institute for Pharmaceutical Sciences
Utrecht University
The Netherlands.

Medical Research: What is the background for this study? What are the main findings?

Dr. van den Ham: Atrial fibrillation (AF) is associated with a substantial risk of ischemic stroke and thromboembolism. The CHADSand the CHA2DS2-VASc risk scores are developed to guide the decision to prescribe anticoagulants. Recently a new clinically-based risk score, the ATRIA study risk score, was developed. We compared the predictive ability of the ATRIA risk score with the CHADS2 and CHA2DS2-VASc risk scores in a large, independent, community-based cohort of Atrial fibrillation patients in the United Kingdom. We found that the ATRIA score more accurately identified low risk patients that the CHA2DS2-VASc score assigned to higher risk categories.  Such reclassification of stroke risk could prevent overuse of anticoagulants in very low stroke risk patients with Atrial fibrillation.

Continue reading

Routine Nuclear Stress Testing in Asymptomatic Atrial Fibrillation Has Low Yield

Wael A. Jaber, MD FACC, FAHA Professor of Medicine Cleveland Clinic Lerner College of Medicine Fuad Jubran Endowed Chair in Cardiovascular Medicine Heart and Vascular Institute Cleveland Clinic Cleveland, OH

MedicalResearch.com Interview with:
Wael A. Jaber, MD FACC, FAHA
Professor of Medicine
Cleveland Clinic Lerner College of Medicine
Fuad Jubran Endowed Chair in Cardiovascular Medicine
Heart and Vascular Institute
Cleveland Clinic  Cleveland, OH

Medical Research: What is the background for this study? What are the main findings?

Prof. Jaber: Risk stratification of patients presenting with atrial fibrillation often includes a non-invasive evaluation for coronary artery disease. However, the yield of such testing in patients without angina or anginal-equivalent symptoms is uncertain. That is, how often do we find silent myocardial ischemia?

In our cohort of 1700 consecutive patients with atrial fibrillation, less than 5% had ischemia on nuclear stress testing, even though comorbidities were prevalent. Moreover, in patients with ischemia that had invasive coronary angiography, less than half had obstructive coronary artery disease.

Continue reading

Atrial Fibrillation Increases Risk of Stroke After TAVR

Prof. Johan Bosmans Interventional cardiologist University Hospital Antwerp, Wilrijkstraat 10, 2650, Edegem, BelgiumMedical Research Interview with:
Prof. Johan Bosmans

Interventional cardiologist
University Hospital Antwerp, Wilrijkstraat 10, 2650,
Edegem, Belgium

MedicalResearch: What is the background for this study? What are the main findings?

Prof. Bosmans : Transcatheter aortic valve replacement (TAVR) has become standard of care for patients who cannot undergo surgery. With this, it is important to ensure that the risks associated with TAVR be fully understood, and if possible prevented. Even at this stage of the adoption of TAVR, large trials continue to provide information to the clinician about how to select the right patients to ensure the best possible outcomes. The ADVANCE Study is a prospective, multicenter study that evaluated the use of TAVR in 1015 patients at 44 experienced TAVR centers, which was designed to reflect routine clinical practice.

We know that the risk of serious adverse events, such as stroke or transient ischemic attack (TIA), in post-TAVR patients can vary based on the timing before and after the procedure. A patient’s baseline demographics and medical history can affect their risk of procedure-related events as well as long-term outcomes. The manipulations required crossing the aortic valve and appropriately positioning any type of TAV has been thought to be related to procedural stroke events. Therefore, we performed a multivariable analysis looking for predictors of stroke – or stroke and TIA at 3 unique time periods (periprocedural, early and late) following TAVR.

The most striking result from our analyses was that we were not able to identify any predictors of periprocedural (either during the procedure or on the day after) stroke, illustrating this very multifactorial etiology. We were able to show that being female, experiencing acute kidney injury or a major vascular complication positively predicted stroke during the early (2-30 days post procedure) time period. When we combined the outcome of stroke or TIA, we found that a history of prior atrial fibrillation (AF) was also a predictor. The only late predictor (day 31-730 post-procedure) of stroke was a history of coronary artery bypass grafting, which could reflect the patients’ risk of vascular disease.

Continue reading

Health Lifestyle Reduces Risk of Atrial Fibrillation

Carl "Chip"  Lavie MD, FACC FACP, FCCP Medical  Director, Cardiac  Rehabilitation and Prevention Director, Exercise Laboratories John Ochsner Heart and Vascular Institute Professor of Medicine Ochsner Clinical  School-UQ School of Medicine Editor-in-Chief, Progress in Cardiovascular DiseasesMedicalResearch.com Interview with:
Carl “Chip”  Lavie MD, FACC FACP, FCCP
Medical  Director, Cardiac  Rehabilitation and Prevention
Director, Exercise Laboratories
John Ochsner Heart and Vascular Institute
Professor of Medicine
Ochsner Clinical  School-UQ School of Medicine
Editor-in-Chief, Progress in Cardiovascular Diseases

Medical Research: What is the background for this study? What are the main findings?

Dr. Lavie: This was a review of the literature on this topic.The main findings are that various lifestyle choices, including obesity,  hypertension, metabolic syndrome/diabetes, obstructive sleep apnea , moderate and  high alcohol intakes, and sedentary lifestyle but also very high exercise doses are all associated with increased risk of atrial fibrillation (AF).

Continue reading

Atrial Fibrillation Increase Leading To More Hospitalizations and Higher Costs

MedicalResearch.com Interview with:
Azfar B. Sheikh, M.D.
Internal Medicine Resident Physician
Staten Island University Hospital
New York

Medical Research: What is the background for this study?

Dr. Sheikh: The background of this review article circles around the impact of
atrial fibrillation on epidemiology, trends in hospitalizations, costs
associated with hospitalization and outpatient care, in the United
States. This article also describes the benefits of newer treatment
modalities compared to the standard of care with regards to
symptomatic improvement and prevention of thromboembolism. These
findings are supported by several cost-utility analyses.

Medical Research: What are the main findings?

Dr. Sheikh:  The main findings of the study are:

  • The cost of hospitalization is three times higher for patients with
    atrial fibrillation than those without atrial fibrillation.
  • 5 million new cases are being reported annually.
  • The incidence of atrial fibrillation is projected to increase from
    1.2 million cases in 2010 to 2.6 million cases by 2030. Due to this
    increase in incidence, the prevalence of atrial fibrillation is
    projected to increase from 5.2 million cases to 12.1 million cases by
    2030.
  • The most common co-moribidites associated with atrial fibrillation
    were hypertension, diabetes mellitus, and chronic obstructive lung
    disease.
  • According to the NIS database, the atrial fibrillation.
    hospitalization rate has increased from 1552 to 1812 per one million
    US residents per year from 2000 to 2010 (relative increase 14.4%).
  • According to the NIS database, the mortality associated with atrial
    fibrillation hospitalizations has decreased significantly from 1.2% in
    2000 to 0.9% in 2010 (relative decrease 29.2%).
  • The median length of stay in the hospital is 3 days and increases
    proportionally with a rise in CHADS2 score.
  • The largest source of direct healthcare costs associated with
    atrial fibrillation is hospitalization. According to the NIS database,
    the mean cost of inpatient atrial fibrillation hospitalization
    increased significantly from $6401 in 2001 to $8439 in 2010 (relative
    increase 24.0%). The mean cost of atrial fibrillation hospitalization
    also increases proportionally with a rise in CHADS2 score.
  • In the outpatient setting, the highest costs were associated with
    physician office visits in comparison to emergency room and urgent
    care visits.
  • With regards to prevention of thromboembolism, the new oral
    anticoagulant agents (dabigatran, rivaroxaban, and apixaban) have been
    found to be more cost-effective compared to warfarin.
  • Left atrial catheter ablation is more effective than rate control
    and rhythm control. It is more cost-effective in younger patients who
    are moderate risk for stroke.

Continue reading

Comorbidities Increase Mortality Risk of Atrial Fibrillation In Blacks and Hispanics

MedicalResearch.com Interview with:
Dr. Mary Vaughan Sarrazin
Ph.D.
Associate Professor
University of Iowa Roy and Lucille Carver College of Medicine, and
Iowa City VA Medical Center, Center for Comprehensive Access & Delivery
Research and Evaluation (CADRE)
Iowa City, IA
Dr. Rajesh Kabra MD
Division of Cardiology, Department of Internal Medicine
University of Tennessee Health Science Center, Memphis, Tennessee

MedicalResearch: What is the background for this study? What are the main findings?

Response: Atrial fibrillation is associated with high risk of stroke and death. It is not known if these outcomes are different in whites, blacks and Hispanics.

In our study of over 500,000 Medicare patients over the age of 65 years with newly diagnosed atrial fibrillation, we noted that compared to whites, blacks and Hispanics had a higher risk of mortality (46% and 11% higher respectively) and stroke (66% and 21% respectively). However after correcting for other co-morbidities and illnesses, the risk of mortality was the same in all the races; the higher risk of stroke was decreased in blacks and eliminated in Hispanics. This suggests that in blacks and Hispanics, atrial fibrillation is a marker for higher mortality and identifies patients at higher risk of death.

Continue reading

Most Patients With Atrial Fibrillation Are Symptomatic and Have Impaired Quality of Life

James V. Freeman MD, MPH, MS Yale University School of Medicine New Haven, CTMedicalResearch.com Interview with:
James V. Freeman MD, MPH, MS
Yale University School of Medicine
New Haven, CT

Medical Research: What is the background for this study? What are the main findings?

Dr. Freeman: Atrial fibrillation (AF) substantially increases the risk of major adverse clinical outcomes such as stroke and death, but it can also cause frequent symptoms, affect patient’s functional status, and impair their quality of life. While prior studies have reported the range of AF-related symptoms in patient populations, these studies were generally from highly selected patients and referral based practices, and may not reflect results in community practice or results with contemporary AF management. Using the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF), a large, contemporary, prospective, community-based outpatient cohort, we evaluated the type and frequency of symptoms in patients with Atrial fibrillation. In addition, we measured the degree to which physician assessed symptom severity (using the European Heart Rhythm Association [EHRA] classification system) was correlated with patient reported quality of life (assessed by the Atrial Fibrillation Effect on QualiTy-of-life [AFEQT] questionnaire). Finally, we association between symptoms or quality of life with clinical outcomes, including death, hospitalization, stroke and major bleeding.

In our community-based study, the majority of AF patients (61.8%) were symptomatic (EHRA >2) and 16.5% had severe or disabling symptoms (EHRA 3-4). EHRA symptom class was well correlated with the AFEQT quality of life score (Spearman correlation coefficient -0.39). Over 1.8 years of follow-up, Atrial fibrillation symptoms were associated with a higher risk of hospitalization (adjusted HR for EHRA ≥2 vs EHRA 1 1.23, 95% CI 1.15-1.31) and a borderline higher risk of major bleeding. Lower quality of life was associated with a higher risk of hospitalization (adjusted HR for lowest quartile of AFEQT vs highest 1.49, 95% CI 1.2-1.84), but not other major adverse events including death. Continue reading

Weight Reduction Lowers Risk of Atrial Fibrillation

MedicalResearch.com Interview with:
Christopher X Wong MBBS MSc PhD
Clinical Research Fellow | Clinical Trial Service Unit, Oxford
Clinical Senior Lecturer | Centre for Heart Rhythm Disorders, Adelaide
Clinical Trial Service Unit, University of Oxford
Roosevelt Drive, Oxford

Medical Research: What is the background for this study? What are the main findings?

Dr. Wong: Atrial fibrillation is an increasingly common heart rhythm disorder. This study demonstrates that even small increments in obesity are associated with a significantly increased risk of atrial fibrillation. Our data suggest that for every 1 unit reduction in body mass index there may be a 3-5% reduction in atrial fibrillation; for every 5 unit reduction, there may be 10-29% reductions. It should also be noted that this is likely to be a significant underestimate of the effect of weight reduction on atrial fibrillation rates as weight control has favourable effects on other risk factors for atrial fibrillation, such as hypertension and diabetes. Given the more than 45 million people with atrial fibrillation worldwide, even small but widespread reductions in obesity would thus help contain this ‘epidemic’ of atrial fibrillation.

Continue reading

CPAP For Sleep Apnea May Decrease Atrial Fibrillation Recurrence

Dr. Larry Chinitz MD Professor of Medicine and Director, Cardiac Electrophysiology NYU Langone Medical CenterMedicalResearch.com Interview with:
Dr. Larry Chinitz MD

Professor of Medicine and Director, Cardiac Electrophysiology
NYU Langone Medical Center

MedicalResearch: What is the background for this study? What are the main findings?

Dr. Chinitz: The treatment algorithms proposed currently for maintenance of sinus rhythm in patients with atrial fibrillation focus on use of anti-arrhythmic drugs and catheter ablation. Data available to evaluate the effect of modification of known adverse clinical factors on atrial fibrillation recurrence is scant.

Obstructive sleep apnea in a known factor associated with both new onset atrial fibrillation as well as its recurrence after catheter ablation. Through a meta-analysis of available data we found that use of continuous positive airway pressure in patients with sleep apnea was associated with a 42% relative risk reduction in recurrence of atrial fibrillation. This effect was similar across patient groups irrespective of whether they were medically managed or with catheter ablation.
Continue reading

Despite High Risk Of Stroke, Some Atrial Fibrillation Patients Not Adequately Anticoagulated

Jonathan L. Halperin, M.D. The Robert and Harriet Heilbrunn Professor of Medicine Mount Sinai School of MedicineMedicalResearch.com Interview with:
Jonathan L. Halperin, M.D.

The Robert and Harriet Heilbrunn Professor of Medicine
Mount Sinai School of Medicine

Dr. Halperin is a member of the Steering Committee for the GLORIA-AF program and a consultant to Boehringer Ingelheim, which sponsored this research.

Medical Research: What is the background for this study? What are the main findings?

Dr. Halperin: The two analyses come from the GLORIA-AF Registry Program, a global, prospective, observational study supported by Boehringer Ingelheim, which is designed to characterize the population of newly diagnosed patients with non-valvular atrial fibrillation (NVAF) at risk for stroke, and to study patterns, predictors and outcomes of different treatment regimens for stroke risk reduction in non-valvular atrial fibrillation patients. The data is based on treatment trends in 3,415 patients who entered the registry from November 2011 to February 2014 in North America. All patients had a recent diagnosis of NVAF, and 86.2 percent had a CHA2DS2-VASc score of 2 or higher.

Results from the first analysis demonstrated that patients with the paroxysmal (occasional) form of non-valvular atrial fibrillation and at a high risk for stroke (CHA2DS2-VASc score of 2 or higher) were given an anticoagulant medication less often than those with persistent or permanent forms of NVAF, and a CHA2DS2-VASc score of 2 or higher. This pattern runs counter to NVAF guidelines calling for patients to receive oral anticoagulant therapy based on their risk of stroke, rather than the type of atrial fibrillation.

In the second analysis, researchers found that despite high stroke risk, a considerable number of patients receive only aspirin or no medication.

Continue reading

Sustained Weight Loss Improves Arial Fibrillation Control

Dr Rajeev Kumar Pathak MBBS, FRACP Cardiologist and Electrophysiology Fellow Centre for Heart Rhythm Disorders | University of Adelaide Cardiovascular Investigation Unit | Royal Adelaide Hospital Adelaide AustraliaMedicalResearch.com Interview with:
Dr Rajeev Kumar Pathak MBBS, FRACP
Cardiologist and Electrophysiology Fellow
Centre for Heart Rhythm Disorders | University of Adelaide
Cardiovascular Investigation Unit | Royal Adelaide Hospital Adelaide Australia

Medical Research: What is the background for this study? What are the main findings?

Response: Obesity and atrial fibrillation (AF) are dual epidemics that frequently coexist. Weight-loss reduces atrial fibrillation burden; however, whether this is sustained, has a dose effect or is influenced by weight-fluctuation is not known. In this study we evaluated the  long-term impact of weight-loss and weight-fluctuation on rhythm control in obese individuals with atrial fibrillation.

Continue reading

Study Weighs Risks/Benefits of Oral Anticoagulation for Atrial Fibrillation in Hemodialysis Patients

Dr. Simonetta Genovesi MD Department of Health Science University of Milano-Bicocca, Monza Italy Nephrology Unit San Gerardo Hospital, Monza, ItalyMedicalResearch.com Interview with: Dr. Simonetta Genovesi MD
Department of Health Science
University of Milano-Bicocca, Monza
Italy Nephrology Unit
San Gerardo Hospital, Monza, Italy

MedicalResearch: What is the background for this study?  

Dr. Genovesi: The prevalence of atrial fibrillation (AF) in patients
with end-stage renal disease (ESRD) on hemodialysis (HD)
is high. The presence of atrial fibrillation increases the risk of
thrombo-embolic stroke in the general population. The
treatment of choice for reducing thrombo-embolic risk in
AF patients is oral anticoagulant therapy (OAT) with
warfarin. However, the use of warfarin in HD patients is
controversial because of the high risk of bleeding and the
fact that it is not demonstrated a clear protection
against the risk of stroke in this population. The purpose
of the study was to prospectively evaluate the effect of
OAT on the risk of mortality, stroke and bleeding in HD
population.

MedicalResearch: What are the main findings?  

Dr. Genovesi: In our hemodialysis population oral anticoagulant therapy does not increase the risk of total mortality, while antiplatelet agents are associated
with an increased risk of death of about 70%. The
continuous use of warfarin tends to be associated with
improved survival as compared with individuals who
discontinued the medication during the follow-up, but the
incidence of thrombo-embolic events is not different in
OAT subjects as compared with those who do not take it.
Moreover, bleeding events are more frequent in patients
taking warfarin, although the maintenance over time of an
INR in the therapeutic range wards against the risk of
bleeding.
Continue reading

Women With Atrial Fibrillation At Greater Risk Of Stroke Than Men

Gregory YH Lip MD, FRCP (London, Edinburgh, Glasgow), DFM, FACC, FESC Professor of Cardiovascular Medicine, University of Birmingham, UK; Adjunct Professor of Cardiovascular Sciences, Thrombosis Research Unit, Aalborg University, Denmark; Visiting Professor of Haemostasis Thrombosis & Vascular Sciences, Aston University, Birmingham, UK; Visiting Professor of Cardiology, University of Belgrade, Serbia Centre for Cardiovascular Sciences City Hospital Birmingham  England UKMedicalResearch.com Interview with:
Gregory YH Lip MD, FRCP (London, Edinburgh, Glasgow), DFM, FACC, FESC
Professor of Cardiovascular Medicine,
Adjunct Professor of Cardiovascular Sciences,
Thrombosis Research Unit, Aalborg University, Denmark;
Aston Centre for Cardiovascular Sciences City Hospital Birmingham
England UK

Medical Research: What is the background for this study? What are the main findings?

Prof. Lip: Women with atrial fibrillation are at higher risk of stroke than men with atrial fibrillation.

The reasons for this elevated risk remain unclear.

The results from our worldwide study suggest that women are treated no differently to men in terms of anticoagulant therapy for stroke prevention.

Thromboprophylaxis was, however, suboptimal in substantial proportions of men and women, with underuse in those at moderate-to-high risk of stroke and overuse in those at low risk.

Continue reading

Sleep Apnea Increases Stroke Risk in Atrial Fibrillation Patients

Dmitry Yaranov, MD Danbury Hospital Western Connecticut Health NetworkMedicalResearch.com Interview with:
Dmitry Yaranov, MD

Danbury Hospital
Western Connecticut Health Network

Medical Research: What is the background for this study? What are the main findings?

Dr. Yaranov: Obstructive sleep apnea (OSA) is an independent risk factor for ischemic stroke (CVA) that is not included in the usual cardioembolic risk assessments for patients with atrial fibrillation. The aim of this study was to investigate the impact of OSA on CVA rate in patients with atrial fibrillation. We found that Obstructive sleep apnea in patients with atrial fibrillation is an independent predictor of CVA and this association may have important clinical implications in CVA risk stratification. Continue reading

ICD-9 Codes Do Not Identify All Strokes in Atrial Fibrillation Patients

Jonathan Thigpen, PharmD Assistant Professor Clinical and Administrative Sciences Notre Dame of Maryland University School of PharmacyMedicalResearch.com Interview with:
Jonathan Thigpen, PharmD
Assistant Professor
Clinical and Administrative Sciences
Notre Dame of Maryland University School of Pharmacy

Medical Research: What is the background for this study? What are the main findings?

Dr. Thigpen: This effort assessed the accuracy of International Classification of Disease 9th Edition (ICD-9) stroke codes in identifying valid stroke events in a cohort of atrial fibrillation (AF) patients. The initial electronic search yielded 1,812 events across three stroke centers (Boston Medical Center, Geisinger Health System, and University of Alabama). All ICD-9 identified stroke events were vetted through manual chart review with final adjudication by a stroke neurologist. Atrial fibrillation was verified by evidence via electrocardiogram at stroke admission, 6 months prior to, or 90 days after stroke admission.

In addition to assessing the accuracy of the stroke codes alone, we also assessed the accuracy of stroke and Atrial fibrillation codes combined as well as the accuracy of stroke codes when seeking for stroke associated with Atrial fibrillation. These additional steps give readers insight as to the accuracy and reliability of using ICD-9 codes alone to create a stroke plus AF cohort. We feel that this effort is extremely important given the increasing reliance on ICD-9 codes as a means of identifying stroke events and covariates in research, especially research using administrative data.

The positive predictive value (PPV) of stroke codes alone was 94.2%. PPVs did not differ across clinical site or by type of event (ischemic vs. intracranial hemorrhage). PPV of stroke codes did differ by event coding position (primary vs. other; 97.2% vs. 83.7%) and by ischemic stroke code (433 vs. 434; 85.2% vs. 94.4%). When combined with validation of Atrial fibrillation codes, the PPV of stroke codes decreased to 82.2%. After excluding ischemic stroke due to a different mechanism (eg, vascular procedure, tumor, sepsis) the PPV dropped further to 72.8%. As a separate exercise, manual review confirmed 33 (7.2%) ischemic strokes in 458 events coded as “without infarction”.

Continue reading

Study Highlights Unpredictable Anticoagulation With Warfarin

Winnie Nelson PharmD, MS, MBA Director, Health Economics & Outcomes Research Janssen PharmaceuticalsMedicalResearch.com Interview with:
Winnie Nelson PharmD, MS, MBA

Director, Health Economics & Outcomes Research
Janssen Pharmaceuticals

Medical Research: What is the background for this study? What are the main findings?

Dr. Nelson: Although warfarin has long served as the standard of care for stroke prevention in patients with nonvalvular atrial fibrillation (NVAF), research has shown nearly one-third of international normalized ratio (INR) levels among stabilized patients on warfarin are out-of-range. Data recently published in the International Journal of Clinical Pharmacy underscores the potential complications of out-of-range INRs, with the aim of informing patient care.

The analysis of a U.S. Veterans Health Administration dataset showed out-of-range INRs were associated with a significantly increased risk of adverse clinical outcomes, including stroke and major bleeding. Of particular interest, the study also showed the magnitude of risk of thromboembolic events – such as ischemic stroke – was several folds higher in sub-therapeutic INR levels (i.e., INR <2) than risk of bleeding events when INR measures were >3. In another words, the research found more risks to patients when INRs were too low than when INRs were too high.
Continue reading