Project description:Purpose of Review:Atrial fibrillation (AF) and dementia are both prevalent diseases in aging societies, which exert a great economic burden worldwide. Although a handful of epidemiologic studies have indicated that AF is independently associated with faster cognitive decline and a higher risk of dementia, there is still a lack of comprehensive understanding of the observed association. In this review, we summarize evidence from major epidemiologic studies concerning AF-related cognitive decline and dementia, the potential mechanisms underlying their association, and the cognitive benefits of treatment options. Recent Findings:A large majority of population-based longitudinal studies have consistently shown an independent association of AF with cognitive decline and dementia with varying effect sizes, depending on the age of the study population and the presence of clinical stroke. The underlying pathways linking AF to cognitive phenotypes may involve systemic inflammation, cerebral hypoperfusion, and cerebral small vessel disease and microemboli. However, current evidence is insufficient to support the potential benefits of AF treatment in reducing risk of cognitive decline and dementia. Summary:Current epidemiologic research suggests that AF contributes to cognitive decline and dementia, independent of a history of stroke. Further work is warranted to elucidate the potential mechanisms underlying this association, and more well-designed studies are needed to explore the possible cognitive benefits of different therapeutic options in patients with AF.
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.
Project description:Background: A potential evidence from previous epidemiological studies remains conflicting findings regarding the association between atrial fibrillation (AF) and dementia risk. We, therefore, carried out a meta-analysis of relevant studies to investigate the magnitude of the association between AF and dementia risk. Methods: We performed a systematic literature search of PubMed, EMBASE, and Google Scholar for potential studies between January 1, 1990, and December 31, 2018, with no restriction on the publication language. All potential studies were independently assessed by two reviewers. We only included observational studies that calculated the odds ratio (OR)/hazards ratio (HR) for dementia associated with atrial fibrillation. We first assessed the heterogeneity among study-specific HRs using the Q statistic and I 2 statistic. We then used the random-effects model to obtain the overall HR and its 95% CI for all studies. We also tested and corrected for publication bias by funnel plot-based methods. The quality of each study was assessed with the Newcastle Ottawa Scale. Results: A total of 16 studies with 2,415,356 individuals, and approximately 200,653 cases of incidence dementia were included in this study. Patients with AF had a greater risk of incidence dementia than those without AF (random-effect hazard ratio HR: 1.36, 95% CI: 1.23-1.51, p < 0.0001; I 2 = 83.58). Funnel plot and Egger test did not reveal significant publication bias. However, limitations of the study included high heterogeneity and varying degrees of confounder adjustment across individual studies. Conclusion: This study serves as added evidence supporting the hypothesis that AF is associated with an increased risk of dementia. More studies are needed to establish whether optimal treatment of AF can reduce or mitigate the risk of dementia.
Project description:BackgroundAssociations between napping and incident atrial fibrillation (AF) remain unknown, and few studies have accounted for dynamic transitions between AF and dementia.ObjectivesThe purpose of this study was to evaluate associations between napping with incident AF and the dynamic transitions of AF and dementia, as well as the mediation pathway of left ventricular (LV) size and function.MethodsA total of 476,588 participants from UK Biobank were included. Napping frequency and other sleep behaviors were evaluated. Incident AF, dementia, and mortality were ascertained via linkage to external registry databases. LV size and function indices were obtained from cardiovascular magnetic resonance imaging phenotypes. A multistate survival analysis was conducted to examine daytime napping in relation to dynamic transitions. Weighed AF genetic risk score was calculated.ResultsFrequent daytime napping, compared to never/rarely napping, was associated with a 1.17-fold AF risk (HR: 1.17; 95% CI: 1.12-1.22), which persisted after controlling for other sleep behaviors. Genetic predisposition significantly modified associations between napping and AF (P for interaction <0.001), with stronger associations observed in those of low and moderate genetic risk. LV ejection fraction significantly mediated 26.2% (95% CI: 4.2%-74.1%) of associations between napping and AF. Frequent napping was also associated with a 1.27-fold risk of transition from AF to comorbidity of AF and dementia.ConclusionsOur findings highlight the potential importance of screening for napping in view of the association with incident AF and dementia. Routine evaluations of the LV ejection fraction could be warranted to timely identify early indications of AF onset among habitual nappers.
Project description:ObjectiveThe aim of this study was to investigate the association between oral anticoagulant type (direct oral anticoagulants (DOACs) vs vitamin K antagonists (VKAs)) and incident dementia or mild cognitive impairment (MCI) among patients with newly diagnosed atrial fibrillation (AF).MethodsUsing linked electronic health record (EHR) data from the Clinical Practice Research Datalink in the UK, we conducted a historical cohort study among first-time oral anticoagulant users with incident non-valvular AF diagnosed from 2012 to 2018. We compared the incidence of (1) clinically coded dementia and (2) MCI between patients prescribed VKAs and DOACs using Cox proportional hazards regression models, with age as the underlying timescale, accounting for calendar time and time on treatment, sociodemographic and lifestyle factors, clinical comorbidities and medications.ResultsOf 39 200 first-time oral anticoagulant users (44.6% female, median age 76 years, IQR 68-83), 20 687 (53%) were prescribed a VKA and 18 513 (47%) a DOAC at baseline. Overall, 1258 patients (3.2%) had GP-recorded incident dementia, incidence rate 16.5 per 1000 person-years. DOAC treatment for AF was associated with a 16% reduction in dementia diagnosis compared with VKA treatment in the whole cohort (adjusted HR 0.84, 95% CI: 0.73 to 0.98) and with a 26% reduction in incident MCI (adjusted HR 0.74, 95% CI: 0.65 to 0.84). Findings were similar across various sensitivity analyses.ConclusionsIncident EHR-recorded dementia and MCI were less common among patients prescribed DOACs for new AF compared with those prescribed VKAs.
Project description:To determine whether atrial fibrillation (AF) is associated with risk of incident dementia or Alzheimer's disease (AD), beyond its effect on stroke.Prospective cohort study.An integrated healthcare delivery system.A population-based sample of 3,045 community-dwelling adults aged 65 and older without dementia or clinical stroke followed from 1994 to 2008.AF was identified from health plan electronic data using International Classification of Diseases, Ninth Revision, codes from inpatient and outpatient encounters. Covariates came from self-report, study measures, and health plan data. Participants were screened every 2 years using the Cognitive Abilities Screening Instrument (range 0-100), with detailed neuropsychological and clinical assessment of those scoring less than 86. A multidisciplinary consensus committee determined diagnoses of all-cause dementia and possible or probable AD using standard research criteria.AF was present in 132 (4.3%) participants at baseline and was diagnosed in 370 (12.2%) more over a mean of 6.8 years of follow-up; 572 participants (18.8%) developed dementia (449 with AD). The adjusted hazard ratio associated with AF was 1.38 (95% confidence interval (CI)=1.10-1.73) for all-cause dementia and 1.50 (95% CI=1.16-1.94) for possible or probable AD. Results were similar for participants with and without clinically recognized stroke during follow-up and in sensitivity analyses examining only probable AD.AF is associated with higher risk of developing AD and dementia. Future studies should examine whether specific treatments, including optimal anticoagulation, can decrease this risk.
Project description:Background and objectives: Atrial fibrillation (AF) and dementia are growing causes of morbidity and mortality, representing relevant medical and socioeconomic burdens. In this study, based on data from the Global Burden of Disease Injuries and Risk Factors Study (GBD) 2019, we focused on AF and dementia distribution and investigated the potential correlation between the two epidemiological trends. Materials and Methods: Crude and age-standardized incidence, prevalence, mortality rate, and disability-adjusted life years (DALYs) lost, derived from GBD 2019, were reported for AF and dementia. Global features were also stratified by high and low sociodemographic-index (SDI) countries. Granger test analysis was performed to investigate the correlation between AF and dementia incidence time trends. Results: From 1990 to 2019 crude worldwide incidence and prevalence showed a dramatic increase for both conditions (from 43.24 to 61.01 and from 528.72 to 771.51 per 100,000 individuals for AF, respectively; from 54.60 to 93.52 and from 369.88 to 667.2 per 100,000 individuals for dementia, respectively). In the same timeframe, crude mortality rate doubled for AF and dementia (from 2.19 to 4.08, and from 10.49 to 20.98 per 100,000 individuals, respectively). Age-standardized estimate showed a substantial stability over the years, highlighting the key role of the progressively aging population. Crude estimates of all of the investigated metrics are greater in high SDI countries for both conditions. This association was still valid for age-standardized metrics, albeit by a reduced magnitude, suggesting the presence of higher risk factor burden in these countries. Finally, according to Granger test, we found a significant association between the historical trends of AF and dementia incidence (p = 0.004). Conclusions: AF and dementia burden progressively increased in the last three decades. Given the potential association between these two conditions, further clinical data assessing this relationship is needed.
Project description:OBJECTIVE:Levothyroxine treatment is common among older adults as is atrial fibrillation (AF), yet less is known about its potential effects on the development of dementia. METHODS:The study population included all adults with diagnosed AF (n = 156,104) aged ≥ 45 years in Sweden without an earlier recorded diagnosis of dementia. Individuals with a dispensed prescription of levothyroxine on two or more occasions between July 1 2005 and December 31 2006 in Sweden were considered exposed (n = 12,978; 8.3%), and were compared to all other patients with AF without this treatment. Cox regression with hazard ratios (HRs) and 95% confidence interval (95% CI), with outcome defined as dementia of all causes between January 1, 2007 and December 31, 2015, was used in the analysis. Adjustments were made for socio-demographic factors (age, immigration status, marital status, educational level, neighborhood socioeconomic status), co-morbidity (cardiovascular disease, obesity, diabetes, COPD, depression, anxiety and alcohol related diagnoses), and cardiovascular medications. RESULTS:During follow-up, a total of 9054 patients with AF were diagnosed with dementia (5.8%). We found no significant association of levothyroxine treatment and incident dementia, fully adjusted HR 1.03 (95% CI 0.96-1.11), neither among men and women, nor in different age-groups or subgroups of dementia. CONCLUSION:We found no significant association of levothyroxine treatment and incident dementia among patients with AF, which contrasts some earlier findings.
Project description:The aim of this study is to perform transcriptome analysis on mouse left atrium tissue after long-term ibrutinib treatment or cardiac CSK knockout, in order to compared the enriched gene clusters.
Project description:This study will report the incidence of atrial fibrillation after elective colorectal cancer resection in the over 65 age group. This will be used to validate a risk model for the development of post-operative atrial fibrillation.
Eligible patients will undergo electrocardiogram based screening for atrial fibrillation, as well as brain natriuretic peptide tests prior to surgery. They will undergo 24 hour holter monitor prior to surgery, and at 30 and 90 days following surgery.
The primary outcome will be occurrence of atrial fibrillation within 90 days of surgery. Secondary outcomes include quality of life change, use of hospital services for atrial fibrillation, and complications of atrial fibrillation. This will be used to validate the pre-existing model for prediction of atrial fibrillation.