Atrial Fibrillation and Risk of Dementia: Epidemiology, Mechanisms, and Effect of Anticoagulation.
Ontology highlight
ABSTRACT:
SUBMITTER: Silva RMFLD
PROVIDER: S-EPMC6365433 | biostudies-literature | 2019
REPOSITORIES: biostudies-literature
Publications
Atrial Fibrillation and Risk of Dementia: Epidemiology, Mechanisms, and Effect of Anticoagulation.
Silva Rose Mary Ferreira Lisboa Da RMFLD Miranda Cláudia Madeira CM Liu Tong T Tse Gary G Roever Leonardo L
Frontiers in neuroscience 20190131
Atrial fibrillation (AF) is one of the cardiovascular risk factors for dementia. Several longitudinal studies have reported an association between AF and dementia independently of stroke history. Although the mechanisms underlying this association are not fully understood, proposed mechanisms include cerebral hypoperfusion, inflammation, genetic factors, cerebral microbleeds, and recurrent silent cerebral ischemia. Oral anticoagulation can be used to minimize risk of cognitive decline and dement ...[more]
Similar Datasets
Project description:AimsTo investigate if patients with atrial fibrillation (AF) without clear indication for oral anticoagulant (OAC) due to perceived low stroke risk may benefit from OAC treatment when also dementia and intracerebral bleeding risks are considered.Methods and resultsRetrospective study of cross-matched national registries of all individuals in Sweden with a hospital diagnosis of AF between 2006 and 2014 (n = 456 960). Exclusion was made of patients with a baseline CHA2DS2-VASc score >1, not counting female sex, and of patients with previous diagnosis of dementia or intracranial bleeding. After exclusions, 91 254 patients remained in the study of whom 43% used OAC at baseline. Propensity score matching and falsification endpoints were used. Treatment with OAC was associated with lower risk of dementia after adjustment for death as a competing risk [subhazard ratio (sHR) 0.62 with 95% confidence interval (CI) 0.48-0.81]. Regarding the composite brain protection endpoint, OAC treatment was associated with an overall 12% lower risk (sHR 0.88, CI 0.72-1.00). This apparent benefit was restricted to patients aged >65 years, whereas OAC treatment of patients <60 years of age without risk factors appeared to do more harm than good.ConclusionLow-risk AF patients who take OAC have lower risk of dementia than those who do not use OAC. Patients age >65 years appear to benefit from OAC treatment irrespective of stroke risk score.
| S-EPMC6642728 | biostudies-literature
Project description:Patients with atrial fibrillation (AF) are at increased thromboembolic risk, and they suffer more severe strokes with worse outcomes. Most thromboembolic complications of AF are eminently preventable with oral anticoagulation, and the increasing numbers of AF patients mean antithrombotic therapy is the most crucial management aspect of this common arrhythmia. Despite the proven efficacy of warfarin, a string of limitations have meant that it is underused by physicians and patients alike. This has prompted a search for new anticoagulants that could overcome many of the inconveniences of dose variability and anticoagulant monitoring associated with warfarin, but without sacrificing efficacy in thromboprophylaxis. The arrival of new oral anticoagulants has been complemented by improved risk stratification schemes, which permit clinicians to easily and reliably identify patients requiring anticoagulation and their bleeding risk. These advances in AF treatment will hopefully translate into improved outcomes for patients, especially as our experience with the new agents grows.
| S-EPMC4711491 | biostudies-other
Project description:Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, affecting up to six million people in the United States and more than 35 million individuals worldwide. Thromboembolism, including stroke, represents the most common AF-related morbidity and mortality and data indicate that anticoagulation can mitigate this risk by 65%. Our understanding of thromboembolism in AF, however, remains incomplete, and the mechanisms by which AF increases thromboembolic risk are areas of ongoing investigation and debate. Current guidelines do not differentiate between the frequency and duration of AF episodes (AF burden) when selecting which patients with AF should be treated with anticoagulation for thromboembolic risk reduction. Recent data, primarily using cardiac implantable electronic devices (CIEDs) such as pacemakers, implantable cardioverter-defibrillators, and implantable loop recorders, however, have challenged this longstanding notion that AF burden does not influence thromboembolic risk. Continuous and automated cardiac rhythm monitoring via CIEDs with accurate and rapid acquisition and transmission of rhythm data also affords the opportunity to study the relationship between AF burden and thromboembolism and novel ways to reduce thromboembolic risk while minimizing the risk associated with chronic anticoagulation use. This manuscript will review the associations between subclinical, CIED-detected atrial arrhythmias and thromboembolic events. It will also discuss the emergence of "tailored anticoagulation," an anticoagulation strategy wherein CIEDs and remote AF monitoring are employed to allow dynamic administration of oral anticoagulation only around episodes of AF, and the holding of anticoagulation during prolonged periods of sinus rhythm when the thromboembolic risk associated with AF is presumably very low.
| S-EPMC7252665 | biostudies-literature
Project description:BackgroundWarfarin reduces ischemic stroke risk in atrial fibrillation (AF) but increases bleeding risk. Novel anticoagulants challenge warfarin as stroke-preventive therapy for AF. They are available at fixed doses but are more costly. Warfarin anticoagulation at a time in therapeutic range (TTR) ?70% is similarly as effective and safe as novel anticoagulants. It is unclear whether AF patients with TTR ?70% will remain stably anticoagulated and avoid the need to switch to a novel anticoagulant. We assessed stability of warfarin anticoagulation in AF patients with an initial TTR ?70%.Methods and resultsWithin the community-based Anticoagulation and Risk Factors in AF (ATRIA) cohort followed from 1996 to 2003, we identified 2841 new warfarin users who continued warfarin over 9 months. We excluded months 1 to 3 to achieve a stable dose. For the 987 patients with TTR ?70% in an initial 6-month period (TTR1; months 4-9), we described the distribution of TTR2 (months 10-15) and assessed multivariable correlates of persistent TTR ?70%. Of patients with TTR1 ?70%, 57% persisted with TTR2 ?70% and 16% deteriorated to TTR2 <50%. Only initial TTR1 ?90% (adjusted odds ratio 1.47, 95% CI 1.07-2.01) independently predicted TTR2 ?70%. Heart failure was moderately associated with marked deterioration (TTR2 <50%); adjusted odds ratio 1.45, 95% CI 1.00-2.10.ConclusionsNearly 60% of AF patients with high-quality TTR1 on warfarin maintained TTR ?70% over the next 6 months. A minority deteriorated to very poor TTR. Patient features did not strongly predict TTR in the second 6-month period. Our analyses support watchful waiting for AF patients with initial high-quality warfarin anticoagulation before considering alternative anticoagulants.
| S-EPMC5015384 | biostudies-literature
Project description:Hypertrophic cardiomyopathy (HCM) represents a common inherited cardiac disorder with well-known complications Including stroke and sudden cardiac death. There is a recognised association between HCM and the development of AF. This review describes the epidemiology of AF within the HCM population and analyses the risk factors for the development of AF. It further discusses the outcomes associated with AF in this population, including the evidence in support of higher stroke risk in patients with HCM with AF compared with the general AF population. Finally, the evidence and recommendations for anticoagulation in this patient group are addressed.
| S-EPMC5522714 | biostudies-other
Project description:BackgroundDifferences in anticoagulation rates and direct oral anticoagulant use by provider specialty may identify an area of practice improvement to reduce future stroke events in patients with atrial fibrillation (AF).Methods and resultsWe examined anticoagulant prescription fills in 388 045 (mean age, 68±15 years; 59% male) patients with incident AF from the MarketScan databases between 2009 and 2014. Provider specialty and filled anticoagulant prescriptions around the time of AF diagnosis (3 months before through 6 months after) were obtained from outpatient services and pharmacy claims. We estimated the association of provider specialty (cardiology versus primary care) with filling oral anticoagulant prescriptions, adjusting for patient characteristics. The risk of stroke and bleeding events also was explored. A total of 235 739 patients (61%) had a cardiology provider claim, whereas 152 306 (39%) were exclusively managed by primary care. Patients seen by cardiology providers were more likely to fill anticoagulant prescriptions than those seen by primary care (39% versus 27%; relative risk, 1.39; 95% confidence interval [CI], 1.37-1.40). Differences were observed for direct oral anticoagulants (relative risk, 1.74; 95% CI, 1.71-1.78) and warfarin (relative risk, 1.24; 95% CI, 1.22-1.26). A reduced risk of stroke events was observed among those seen by cardiology providers (hazard ratio, 0.90; 95% CI, 0.86-0.94) compared with primary care, without an increased bleeding risk (hazard ratio, 1.03; 95% CI, 0.98-1.07).ConclusionsPatients seen by an outpatient cardiology provider shortly after AF diagnosis were more likely to initiate oral anticoagulation and were at lower risk of future stroke events without a higher rate of bleeding. Early referral to cardiology specialists may increase initiation of anticoagulant therapies and improve outcomes in AF.
| S-EPMC5907557 | biostudies-literature
Project description:BackgroundOral anticoagulation (OAC) reduces the risk of thromboembolic events in patients with atrial fibrillation (AF); however, thromboembolism (TE) still can occur despite OAC. Factors associated with residual risk for stroke, systemic embolism, or transient ischemic attack events despite OAC have not been well described.ObjectiveThe purpose of this study was to evaluate the residual risk of thromboembolic events in patients with AF despite OAC.MethodsA total of 18,955 patients were analyzed in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF I and II) using multivariable Cox proportional hazard modeling. Mean age was 72 ± 10.7, and 42% were women. There were 451 outcome events.ResultsThe risk of TE despite OAC increased with CHA2DS2-VASc score: 0.76 (95% confidence interval [CI] 0.63-0.92) events per 100 patient-years for CHA2DS2-VASc score <4 vs 2.01 (95% CI 1.81-2.24) events per 100-patient years for CHA2DS2-VASc score >4. Factors associated with increased risk were previous stroke or transient ischemic attack (hazard ratio [HR] 2.87; 95% CI 2.30-3.59; P <.001), female sex (HR 1.52; 95% CI 1.24-1.86; P <.001), hypertension (HR 1.50; 95% CI 1.09-2.06; P = .01), and permanent AF (HR 1.47; 95% CI 1.12-1.94; P = .001). When transient ischemic attack was excluded, the results were similar, but permanent AF was no longer significantly associated with thromboembolic events.ConclusionPatients with AF have a residual risk of TE with increasing CHA2DS2-VASc score despite OAC. Key risk markers include previous stroke/transient ischemic attack, female sex, hypertension, and permanent AF.
| S-EPMC9795305 | biostudies-literature
Project description:OBJECTIVE:To study the association between time in therapeutic range (TTR) during warfarin therapy and risk of dementia in a population-based cohort of incident atrial fibrillation (AF). PATIENTS AND METHODS:We conducted an observational population-based study of 2800 nondemented patients with incident AF from January 1, 2000, through December 31, 2010. The association of incident dementia with warfarin therapy and TTR was examined using Cox proportional hazards regression models. RESULTS:Mean patient age was 71.2 years; 53% were men (n=1495), and warfarin was prescribed to 50.5% (n=1414) within 90 days of AF diagnosis. Incident dementia diagnosis occurred in 357 patients (12.8%) over a mean ± SD follow-up of 5.0±3.7 years. After adjusting for confounders, warfarin therapy was associated with a reduced incidence of dementia (hazard ratio [HR], 0.80; 95% CI, 0.64-0.99). However, only those in the 2 highest quartiles of TTR were associated with lower risk of dementia. A 10% increase in TTR with a 10% reduction in time spent in the subtherapeutic (HR, 0.71; 95% CI, 0.64-0.79) and supratherapeutic (HR, 0.67; 95% CI, 0.57-0.79) ranges were associated with decreased risk of dementia. CONCLUSION:In the community, warfarin therapy for AF is associated with a 20% reduction in risk of dementia. Increasing TTR on warfarin is associated with reduced risk of dementia. The risk of dementia was reduced with a reduction in time spent in subtherapeutic and supratherapeutic international normalized ratio range. Effective anticoagulation may prevent cognitive impairment in patients with AF.
| S-EPMC5814135 | biostudies-literature
Project description:Although dementia and atrial fibrillation (AF) are common in older adults, risk factors for dementia have not been sufficiently characterized in patients with AF. We studied 621,773 patients with AF without dementia at the time of AF diagnosis who were enrolled in the MarketScan Commercial and Medicare Supplemental databases from 2007 to 2015. Dementia incidence and presence of predictors at the time of AF diagnosis (cardiometabolic conditions, mental and neurologic disorders, and other chronic conditions) were based on International Classification of Diseases, Ninth Revision, Clinical Modification codes in outpatient and inpatient claims, whereas medication usage was based on outpatient pharmacy claims. A frailty score was calculated using a previously established algorithm. The associations between the predictors of interest and dementia were assessed with multivariable Cox models. Patients had a mean age of 68 years (SD 14 years) and 41% were women. During a mean follow-up of 2.0 years, there were 16,073 cases of dementia. The strongest predictors of dementia were frailty (hazard ratio [HR] 1.43, 95% confidence interval [CI] 1.40 to 1.45, per 1-SD increase in the score), cognitive impairment (HR 1.50, 95% CI 1.36 to 1.65), mood disorders (HR 1.49, 95% CI 1.32 to 1.70), schizophrenia (HR 1.86, 95% CI 1.75 to 1.98), and substance abuse (HR 1.58, 95% CI 1.39 to 1.80). Among cardiometabolic conditions, only stroke (HR 1.17, 95% CI 1.13 to 1.22) and diabetes mellitus (HR 1.14, 95% CI 1.11 to 1.18) were associated with small increases in dementia risk after adjusting for demographics, frailty, co-morbidities, and medications. We have identified several risk factors for dementia in patients with AF.
| S-EPMC9181692 | biostudies-literature
Project description:Management of atrial fibrillation (AF) is a clinical conundrum in people with kidney failure. Stroke risk is disproportionately high, but clinicians have a limited armamentarium to improve outcomes in this population in whom there is a concurrently high bleeding risk. Direct oral anticoagulants may have a superior benefit-risk profile compared with vitamin K antagonists in people on hemodialysis. Although research has predominantly focused on identifying a safe and effective oral anticoagulation option to reduce stroke risk in people with kidney failure (and predominantly those on hemodialysis), it remains uncertain how clinicians discriminate between people who would derive net clinical benefit as opposed to net harm. The recommended CHA2DS2-VASc score cutoffs provide poor discriminatory value, and there is an urgent need to identify robust markers of thromboembolic risk in kidney failure. There is increasing data to challenge the prior dogma of risk equivalence across AF type, and the American Heart Association highlights moving beyond AF as a binary entity to consider the prognostic significance of AF burden. Implantable cardiac monitor studies reveal high rates and varied burden of subclinical and paroxysmal AF in people on hemodialysis. The association between AF burden and the proarrhythmic environment of hemodialysis with cyclical volume loading, offloading, and electrolyte changes is not well studied. We review the significance of AF burden as a contributor to thromboembolic risk, its potential as the missing link in risk assessment, and updated evidence for anticoagulation in people with kidney failure.
| S-EPMC10403723 | biostudies-literature