Is female sex a risk factor for stroke and thromboembolism in patients with atrial fibrillation? A systematic review and meta-analysis

Ischaemic stroke in women with atrial fibrillation: temporal trends and clinical implications

BACKGROUND AND AIMS

Female sex has been linked with higher risk of ischaemic stroke (IS) in atrial fibrillation (AF), but no prior study has examined temporal trends in the IS risk associated with female sex.

METHODS

The registry-linkage Finnish AntiCoagulation in Atrial Fibrillation (FinACAF) study included all patients with AF in Finland from 2007 to 2018. Ischaemic stroke rates and rate ratios were computed.

RESULTS

Overall, 229 565 patients with new-onset AF were identified (50.0% women; mean age 72.7 years). The crude IS incidence was higher in women than in men across the entire study period (21.1 vs. 14.9 events per 1000 patient-years, P < .001), and the incidence decreased both in men and women. In 2007-08, female sex was independently associated with a 20%-30% higher IS rate in the adjusted analyses, but this association attenuated and became statistically non-significant by the end of the observation period. Similar trends were observed when time with and without oral anticoagulant (OAC) treatment was analysed, as well as when only time without OAC use was considered. The decrease in IS rate was driven by patients with high IS risk, whereas in patients with low or moderate IS risk, female sex was not associated with a higher IS rate.

CONCLUSIONS

The association between female sex and IS rate has decreased and become non-significant over the course of the study period from 2007 to 2018, suggesting that female sex could be omitted as a factor when estimating expected IS rates and the need for OAC therapy in patients with AF.

Sex as a Risk Factor for Atrial Fibrillation-Related Stroke

Stroke prevention is crucial for the management of patients with atrial fibrillation (AF), and several risk factors have been identified, which increase the risk of AF-related stroke. Among these factors, female sex has been repeatedly associated with AF-related stroke risk; nonetheless, trends toward lower use of oral anticoagulant in women with AF were also reported. In this clinical focus, we discuss about the role of female sex as a risk factor for AF-related stroke, and reflect on the clinical implications of its inclusion among the risk factors for thromboembolic risk stratification in patients with AF.

Large regional variation in cardiac closure procedures to prevent ischemic stroke in Switzerland a population-based small area analysis

BACKGROUND

Percutaneous closure of a patent foramen ovale (PFO) or the left atrial appendage (LAA) are controversial procedures to prevent stroke but often used in clinical practice. We assessed the regional variation of these interventions and explored potential determinants of such a variation.

METHODS

We conducted a population-based analysis using patient discharge data from all Swiss hospitals from 2013-2018. We derived hospital service areas (HSAs) using patient flows for PFO and LAA closure. We calculated age-standardized mean procedure rates and variation indices (extremal quotient [EQ] and systematic component of variation [SCV]). SCV values >5.4 indicate a high and >10 a very high variation. Because the evidence on the efficacy of PFO closure may differ in patients aged <60 years and ≥60 years, age-stratified analyses were performed. We assessed the influence of potential determinants of variation using multilevel regression models with incremental adjustment for demographics, cultural/socioeconomic, health, and supply factors.

RESULTS

Overall, 2574 PFO and 2081 LAA closures from 10 HSAs were analyzed. The fully adjusted PFO and LAA closure rates varied from 3 to 8 and from 1 to 9 procedures per 100,000 persons per year across HSAs, respectively. The regional variation was high with respect to overall PFO closures (EQ 3.0, SCV 8.3) and very high in patients aged ≥60 years (EQ 4.0, SCV 12.3). The variation in LAA closures was very high (EQ 16.2, SCV 32.1). In multivariate analysis, women had a 28% lower PFO and a 59% lower LAA closure rate than men. French/Italian language areas had a 63% lower LAA closure rate than Swiss German speaking regions and areas with a higher proportion of privately insured patients had a 86% higher LAA closure rate. After full adjustment, 44.2% of the variance in PFO closure and 30.3% in LAA closure remained unexplained.

CONCLUSIONS

We found a high to very high regional variation in PFO closure and LAA closure rates within Switzerland. Several factors, including sex, language area, and insurance status, were associated with procedure rates. Overall, 30-45% of the regional procedure variation remained unexplained and most probably represents differing physician practices.

Temporal trends of gender disparities in oral anticoagulant use in patients with atrial fibrillation

AIMS

To investigate sex-specific temporal trends in the initiation of oral anticoagulant (OAC) therapy among patients diagnosed with atrial fibrillation (AF) in Finland between 2007 and 2018.

METHODS

The registry-linkage Finnish AntiCoagulation in Atrial Fibrillation (FinACAF) Study included all patients with incident AF in Finland from 2007 to 2018. The primary outcome was the initiation of any OAC therapy.

RESULTS

We identified 229,565 patients with new-onset AF (50.0% women; mean age 72.7 years). The initiation of OAC therapy increased continuously during the observation period. While women were more likely to receive OAC therapy overall, after adjusting for age, stroke risk factors and other confounding factors, female sex was associated with a marginally lower initiation of OACs (unadjusted and adjusted hazard ratios comparing women to men: 1.08 (1.07-1.10) and 0.97 (0.96-0.98), respectively). Importantly, the gender disparities in OAC use attenuated and reached parity by the end of the observation period. Furthermore, when only patients eligible for OAC therapy according to the contemporary guidelines were included in the analyses, the gender inequalities in OAC initiation appeared minimal. Implementation of direct OACs for stroke prevention was slightly slower among women.

CONCLUSION

This nationwide retrospective cohort study covering all patients with incident AF in Finland from 2007 to 2018 observed that although female sex was initially associated with a lower initiation of OAC therapy, the sex-related disparities resolved over the course of the study period.

Sex Differences in Atrial Fibrillation and Associated Complications in Hypertensive Patients with Left Ventricular Hypertrophy: The LIFE Study

BACKGROUND

There is no consensus on whether biological differences account for the higher risk of stroke seen in females compared to males with atrial fibrillation (AF).

METHODS

Capitalizing on The Losartan Intervention for Endpoint study, a multicenter randomized clinical trial randomizing 9,193 patients and followed for at least four years, we aimed to identify sex differences in the risk of stroke in the presence of AF in patients with hypertension and left ventricular hypertrophy (LVH).

RESULTS

342 Patients had a history of AF, and 669 developed new-onset AF. History of AF and new-onset AF were more prevalent among males (5.0% vs. 2.9% and 3.0% vs. 0.9%) in patients aged 55-63 years, but the relative difference decreased with age. Females with new-onset AF tended to have a higher risk of stroke than males (HR 1.52 [95% CI 0.95-2.43]). However, females with a history of AF did not have a higher risk than males (HR 0.88 [95% CI 0.5-1.6]). In patients with new-onset AF, the relative higher stroke risk in females increased with age. Among patients with a history of AF, stroke risk was comparable and increased with age in both sexes.

CONCLUSIONS

Among patients with hypertension and LVH, females with new-onset AF had a higher risk of stroke than males, especially in patients above 64 years. However, the risk did not differ between the sexes among patients with a history of AF.

Female "Paradox" in Atrial Fibrillation-Role of Left Truncation Due to Competing Risks

Female sex in patients with atrial fibrillation (AF) is a controversial and paradoxical risk factor for stroke-controversial because it increases the risk of stroke only among older women of some ethnicities and paradoxical because it appears to contradict male predominance in cardiovascular diseases. However, the underlying mechanism remains unclear. We conducted simulations to examine the hypothesis that this sex difference is generated non-causally through left truncation due to competing risks (CR) such as coronary artery diseases, which occur more frequently among men than among women and share common unobserved causes with stroke. We modeled the hazards of stroke and CR with correlated heterogeneous risk. We assumed that some people died of CR before AF diagnosis and calculated the hazard ratio of female sex in the left-truncated AF population. In this situation, female sex became a risk factor for stroke in the absence of causal roles. The hazard ratio was attenuated in young populations without left truncation and in populations with low CR and high stroke incidence, which is consistent with real-world observations. This study demonstrated that spurious risk factors can be identified through left truncation due to correlated CR. Female sex in patients with AF may be a paradoxical risk factor for stroke.

Mortality on DOACs Versus on Vitamin K Antagonists in Atrial Fibrillation: Analysis of the Hungarian Health Insurance Fund Database

PURPOSE

Limited real-world data are available on the survival of patients treated with vitamin K antagonists (VKAs) versus with direct oral anticoagulants (DOACs) for nonvalvular atrial fibrillation (AF). In this nationwide registry, we analyzed the mortality risk of patients with nonvalvular AF taking DOACs versus VKAs, with a special attention to the early treatment period.

METHODS

The Hungarian National Health Insurance Fund (NHIF) database was searched to identify patients treated with VKA or DOAC as a thromboembolic prophylaxis for nonvalvular AF between 2011 and 2016. The overall and the early (0-3, 4-6, and 7-12 months) mortality risks with the 2 types of anticoagulation were compared. A total of 144,394 patients with AF treated with either a VKA (n = 129,925) or a DOAC (n = 14,469) were enrolled.

FINDINGS

A 28% improvement in 3-year survival with DOAC treatment compared with VKA treatment was shown. Mortality reduction with DOACs was consistent across different subgroups. However, younger patients (30-59 years old) initiated on DOAC therapy had the greatest RRR (53%) in mortality. Furthermore, DOAC treatment also yielded a benefit of greater magnitude (HR = 0.55; 95% CI, 0.40-0.77, P = 0.001) in the lower (0-1) CHA₂DS₂-VASc score segment and in those with fewer (0-1) bleeding risk factors (HR = 0.50, CI 0.34-0.73, P = 0.001). The RRR in mortality with DOACs was 33% within the first 3 months, and 6% in the second year.

IMPLICATIONS

Thromboembolic prophylaxis with DOACs in this study yielded significantly lower mortality compared with VKA treatment in patients with nonvalvular AF. The largest benefit was shown in the early period after treatment initiation, as well as in younger patients, those with a lower CHA₂DS₂-VASc score, and those with fewer bleeding risk factors.

R2CHA2DS2-VA predicts the cardiovascular risk after carotid endarterectomy

OBJECTIVE

R2CHA2DS2-VA score has been used to predict short and long-term outcomes in many cardiovascular diseases. This study aims to validate the R2CHA2DS2-VA score as a long-term major adverse cardiovascular events (MACE) predictor after CEA. Secondary outcomes were also assessed regarding the incidence of all-cause mortality, acute myocardial infarction (AMI), major adverse limb events (MALE), and acute heart failure (AHF).

METHODS

From January 2012 to December 2021, patients (n= 205) from a Portuguese tertiary care and referral center that underwent CEA with regional anesthesia (RA) for carotid stenosis were selected from a previously collected prospective database, and a post-hoc analysis was performed. Demographics and comorbidities were registered. Clinical adverse events were assessed 30-days after the procedure and in the subsequent long-term surveillance period. Statistical analysis was performed by the Kaplan-Meier method and Cox proportional hazards regression.

RESULTS

Of the patients enrolled, 78.5% were males with a mean age of 70.44 ± 8.9 years. Higher scores of R2CHA2DS2-VA were associated with long-term MACE (adjusted Hazard Ratio (aHR) 1.390; 95% Confidence Interval (CI) 1.173-1.647) and mortality (aHR 1.295; 95% CI 1.08-1.545) CONCLUSIONS: This study demonstrated the potential of the R2CHA2DS2-VA score to predict long-term outcomes such as AMI, AHF, MACE, and all-cause mortality in a population of patients submitted to carotid endarterectomy.

Ethnodemographic characterization of stroke incidence and burden of disease in hospital discharge records in Ecuador

Introduction

Stroke is the second most common cause of death and disability-adjusted life years (DALYs) globally. However, the incidence and impact of stroke by ethnicity and gender is frequently distinct. This is particularly the case in Ecuador where geographic and economic marginalization are often correlated with ethnic marginalization and the extent to which females lack the same opportunities as their male counterparts. The aim of this paper is to investigate the differential impacts in terms of stroke diagnosis and burden of disease by ethnicity and gender, using hospital discharge records over the years 2015-2020.

Methods

This paper calculates stroke incidence, and fatality rates using hospital discharge and death records over the years 2015-2020. The DALY package in R was employed to calculate the Disability Adjusted Life Years lost due to stroke in Ecuador.

Results

The results show that while the incidence rate of stroke in males (64.96 per 100,000 persons-year) is higher than that for females on average (57.84 per 100,000 persons-year), males accounted for 52.41% of all stroke cases and 53% of all surviving cases. Thus, hospital data suggests that females had a higher death rate when compared to males. Case fatality rates also differed significantly by ethnicity. The highest fatality rate corresponded to the Montubio ethnic group (87.65%), followed by Afrodescendants (67.21%). The estimated burden of disease of stroke calculated using Ecuadorian hospital records (2015-2020) varied from 1,468 to 2,991 DALY per 1,000 population on average.

Discussion

Differences in the burden of disease by ethnic group are likely to reflect differential access to care by region and socio-economic group, both of which are frequently correlated with ethnic composition in Ecuador. Equitable access to health services remains an important challenge in the country. The gender discrepancy in fatality rates suggests that there is a need for targeted educational campaigns to identify stroke signs early, especially in the female population.

Gender Differences in Atrial Fibrillation: From the Thromboembolic Risk to the Anticoagulant Treatment Response

Atrial fibrillation (AF) is the most common cardiac arrhythmia associated with an increased thromboembolic risk. The impact of the female sex as an independent risk factor for thromboembolic events in AF is still debated. Background and Objectives: The aim of this review is to evaluate the gender-related differences in cardioembolic risk and response to anticoagulants among AF patients. Materials and Methods: The PubMed database is used to review the reports about gender differences and thromboembolic risk in atrial fibrillation. Results: Non-vitamin K oral anticoagulants (NOACs) represent the gold standard for thromboembolic risk prevention in patients with non-valvular atrial fibrillation (NVAF). Despite a similar rate of stroke and systemic embolism (SE) among men and women in NOACs or vitamin K antagonists (VKAs) treatment, the use of NOACs in AF women is associated with a lower risk of intracranial bleeding, major bleeding, and all-cause mortality than in men. Conclusions: The female sex can be defined as a stroke risk modifier rather than a stroke risk factor since it mainly increases the thromboembolic risk in the presence of other risk factors. Further studies about the efficacy and safety profile of NOACs according to sex are needed to support clinicians in performing the most appropriate and tailored anticoagulant therapy, either in male or female AF patients.

Validation of CHA2DS2 VASc Score Predictability of Stroke and Systemic Embolization in a Middle Eastern Population with AF: The Jordan Atrial Fibrillation (JoFib) Study

Background and Purpose

CHA2DS2-VASc score is one of the most widely used scoring systems to assess the risk of systemic embolization and stroke in patients suffering from atrial fibrillation (Afib); furthermore, it is important in guiding their treatment. This study aimed to evaluate the predictivity of this score in the Jordanian population, build a deeper understanding of patients' demographic and risk factors, and assess the usefulness of anticoagulation as a preventive measure.

Methods

A total of 2020 patients with Afib registered in the Jordanian Atrial Fibrillation (JoFib) registry were enrolled in this study. All patients were followed up for 1 year to assess their susceptibility to develop cerebrovascular accident (CVA) and systemic embolism (SE). The association between CHA2DS2-VASc score and risk of development of stroke or systemic embolization was analyzed based on bivariate and adjusted multivariate analyses. The ROC curve was used to assess the predictivity of the CHA2DS2-VASc score.

Results

The mean age of the study population was 67.8 years; 45.8% were males, and 81.8% were on anticoagulants. And, 71.8% had a CHA2DS2-VASc score of ≥3. During the follow-up period of 1 year; 69 developed new CVA (mean age, 72.8 years), and 9 developed SE. A total of 276 patients died; 18 patients died (6.5% out of all deceased)% from CVA. A moderate predictive power of the CHA2DS2-VASc score was demonstrated through ROC curve analysis with C statistics of 0.689 CI (0.634 to 0.744) for predicting the development of SE or CVA at 1 year.

Conclusion

CHA2DS2-VASc showed a moderate predictivity of stroke, SE, and all-cause mortality at 1 year. The study suggested disregarding gender differences in deciding to initiate anticoagulant therapy.

Vascular Cognitive Impairment: A Little Bit of Good News for Women or Bad News for Men?

In a recent issue of the Journal of Alzheimer's Disease, Zinman et al. investigated the role of sex in the risk of cognitive impairment in 5,969 patients with a stroke or transient ischemic attacks. Using a short validated clinical screening tool, they noted that men had a 34% higher risk of screening positive for post-stroke cognitive impairment after adjusting for age, education, and stroke severity compared to women. This study highlights that more large, prospective, and multicenter studies are needed to evaluate sex-specific changes after a stroke since sex differences exist in many aspects of stroke presentation and management.

Stroke Prevention in Atrial Fibrillation

PURPOSE OF REVIEW

Atrial fibrillation is associated with a significant increase in stroke and systemic embolism. This review explores the areas of stroke prevention.

RECENT FINDINGS

In the last decade, NOAC has overtaken warfarin as the anticoagulant of choice for stroke prevention in AF. For patients unable to take anticoagulation, LAA closure has proven to be a valid option. The use of digital devices has led to widespread consumer-directed AF screening. It remains to be determined if all device detect AF pose the same amount of risk as recent studies have shown that short and infrequent episodes of AF may not benefit from anticoagulation. Stroke prevention is paramount in the management of AF. In this review we describe the risk factors contributing to stroke, recent advances in antithrombotic therapies, and the increasing role of digital health in guiding AF detection and stroke prevention.

Racial, ethnic, and sex disparities in atrial fibrillation management: rate and rhythm control

BACKGROUND

Atrial fibrillation (AF) affects around 6 million Americans. AF management involves pharmacologic therapy and/or interventional procedures to control rate and rhythm, as well as anticoagulation for stroke prevention. Different populations may respond differently to distinct management strategies. This review will describe disparities in rate and rhythm control and their impact on outcomes among women and historically underrepresented racial and/or ethnic groups.

METHODS

This is a narrative review exploring the topic of sex and racial and/or ethnic disparities in rate and rhythm management of AF. We describe basic terminology, summarize AF epidemiology, discuss diversity in clinical research, and review landmark clinical trials.

RESULTS

Despite having higher rates of traditional AF risk factors, Black and Hispanic adults have lower risk of AF than non-Hispanic White (NHW) patients, although those with AF experience more severe symptoms and report lower quality-of-life scores than NHW patients with AF. NHW patients receive antiarrhythmic drugs, cardioversions, and invasive therapies more frequently than Black and Hispanic patients. Women have lower rates of AF than men, but experience more severe symptoms, heart failure, stroke, and death after AF diagnosis. Women and people from diverse racial and ethnic backgrounds are inadequately represented in AF trials; prevalence findings may be a result of underdetection.

CONCLUSION

Race, ethnicity, and gender are social determinants of health that may impact the prevalence, evolution, and management of AF. This impact reflects differences in biology as well as disparities in treatment and representation in clinical trials.

Sex-Related Differences in Clinical Outcomes in Patients with Atrial Fibrillation and Coronary Artery Disease: A Sub-Study of the MISOAC-AF Randomized Controlled Trial

BACKGROUND

There is limited "real-world" data on the prognostic role of gender in comorbid atrial fibrillation (AF) and coronary artery disease (CAD).

METHODS

In this post-hoc analysis of the MISOAC-AF randomized trial (NCT: 02941978), consecutive patients with AF and CAD who were discharged from the cardiology ward between 2015 and 2018 were included. Multivariable Cox-regression analysis was performed for all-cause mortality and cardiovascular (CV) mortality. Competing-risk analysis was performed for the outcomes of stroke or systemic embolism, major bleeding, AF- or heart failure (HF)-related hospitalization, adjusted for the competing risk of all-cause death.

RESULTS

Of 1098 patients with AF, 461 patients with comorbid CAD were analyzed. Women were older and more likely to have a history of diabetes mellitus and valvular heart disease, while men were more likely to have a history of smoking or myocardial infarction. Over a median follow-up of 31 months, 143 (43.4%) men and 71 (53.7%) women died. Women were at a higher risk for all-cause mortality (adjusted hazard ration [aHR] 1.65; 95% confidence interval [CI] 1.14-2.38) and stroke or systemic embolism (aHR 3.52; 95% CI 1.46-8.49) compared to men. The risks of CV mortality, major bleeding, AF-related hospitalization, and HF-related hospitalization were similar between genders.

CONCLUSIONS

In recently hospitalized patients with AF and comorbid CAD, the female gender was independently associated with increased all-cause mortality and thromboembolic events.

Temporal Trends and Sex Differences in Patients with Cardiac Amyloidosis and Heart Failure with Preserved Ejection Fraction: Retrospective analysis of 22,015 Admissions from the National Inpatient Sample

Cardiac amyloidosis (CA) often goes unrecognized as a cause of heart failure with preserved ejection fraction (HFpEF). There is paucity of contemporary data evaluating the trends of CA diagnosis and associated sex differences. Adult heart failure hospitalizations were identified from the National Inpatient Sample between 2016 and 2019. Hospitalizations with heart failure other than HFpEF were excluded. Hospitalizations with a diagnosis of CA were identified. A Linear regression was utilized to calculate the trend of CA diagnosis over time. A multivariate logistic regressions analysis was performed to analyze sex differences. There was an increasing trend of CA from 1.2 to 2.3 per 1000 HFpEF admission in the first quarter of 2016 to the fourth quarter of 2019 (P_trend <0.001). In females, as compared to males, there was an increased risk of AIS (6% vs 3%, aOR: 1.68[1.24-2.27], P=0.001) and major bleeding events (10% vs 5%, aOR: 1.97[1.53-2.52], P<0.001). No difference was observed in the in-hospital mortality outcome (8% vs 7%, aOR: 1.2[0.95-1.53], P=0.12) between both groups. Our real-world contemporary analysis showed an increase in CA diagnosis from 2016 to 2019. Despite similar in-hospital mortality, females were associated with higher AIS and major bleeding events rates. Further prospective studies are needed to validate these results.

Sex differences in neurovascular disorders

Neurovascular disorders is a heterogenous group of diseases, including one of the most time critical disorders in emergency medicine; stroke. Sex differences are extensively described in neurovascular disorders, ranging from differences in symptom presentation, risk factors, treatment and outcomes. For example, women with stroke, more often present with generalized weakness, reduced consciousness and headache than men. Furthermore, there are differences in risk factors, outcomes and in the effect of secondary prevention. Women have a higher risk of cerebral venous thrombosis and developing cerebral aneurysms. In general, women have been underrepresented in trials on neurovascular disorders. This chapter provides an extensive overview of sex differences in stroke in general and in the differences specially seen in ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage and in cerebral venous thrombosis.

Effects of Interleukin-17A on the Early Stages of Arterial Thrombosis in Mice

PURPOSE

Interleukin (IL)-17A has been suggested to play a role in the growth and organization of thrombi. We examined whether IL-17A plays a role in the early stages of thrombosis and whether there are sex differences in the effects of IL-17A.

MATERIALS AND METHODS

We performed a blinded, randomized, placebo-controlled study to compare time to thrombotic occlusion and sex differences therein between mice treated with IL-17A and those treated with saline using a ferric chloride-induced model. We also assessed thrombus histology, blood coagulation, and plasma levels of coagulation factors.

RESULTS

Time to occlusion values did not differ between the IL-17A group and the control group (94.6±86.9 sec vs. 121.0±84.4 sec, p=0.238). However, it was significantly shorter in the IL-17A group of female mice (74.6±57.2 sec vs. 130.0±76.2 sec, p=0.032). In rotational thromboelastometry, the IL-17A group exhibited increased maximum clot firmness (71.3±4.5 mm vs. 66.7±4.7 mm, p=0.038) and greater amplitude at 30 min (69.7±5.2 mm vs. 64.5±5.3 mm, p=0.040) than the control group. In Western blotting, the IL-17A group showed higher levels of coagulation factor XIII (2.2±1.5 vs. 1.0±0.9, p=0.008), monocyte chemoattractant protein-1 (1.6±0.6 vs. 1.0±0.4, p=0.023), and tissue factor (1.5±0.6 vs. 1.0±0.5, p=0.003).

CONCLUSION

IL-17A plays a role in the initial st ages of arterial thrombosis in mice. Coagulation factors and monocyte chemoattractant protein-1 may be associated with IL-17A-mediated thrombosis.

Sex-Related Differences in Left Atrial Low-Voltage Areas According to CHA2DS2-VA Scores among Patients with Atrial Fibrillation

(1) Background: We hypothesized that female sex would have a differential impact on left atrial (LA) low-voltage areas (LVAs) according to CHA2DS2-VA scores. (2) Methods: This study included 553 patients who underwent radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF). LVAs were defined as regions with bipolar peak-to-peak voltages of <0.5 mV. The proportion of LVAs was calculated by dividing the total LVA by the LA surface area. (3) Results: There was no sex-related difference in LA LVAs among patients with a CHA2DS2-VA scores ≤ 2. The proportion of LVAs was significantly higher in females among patients with CHA2DS2-VA scores of 3 or 4 (10.1 (4.7−15.1)% vs. 15.8 (9.2−32.1)%; p = 0.027). Female sex was significantly associated with extensive LVAs (LVA proportion ≥ 30%). Females had odd ratios of 27.82 (95% confidence interval (CI) 3.33−756.8, p = 0.01), and 1.53 (95% CI 0.81−2.83, p = 0.184) for extensive LAVs in patients with CHA2DS2-VA scores ≥ 3 and CHA2DS2-VA scores < 3, respectively. In the multiple regression model, female patients with a CHA2DS2-VA ≥3 were significantly associated with a higher proportion of LVAs (β = 8.52, p = 0.039). (4) Conclusions: Female sex was significantly associated with extensive LVAs, particularly when their CHA2DS2-VA scores were ≥3. This result suggests that female sex has a differential effect on the extent of LVAs based on the presence of additional risk factors.

Validation of the CHA2DS2-VA Score (Excluding Female Sex) in Nonvalvular Atrial Fibrillation Patients: A Nationwide Population-Based Study

Sex (i.e., female sex) confers one point for the CHA2DS2-VASc score. For this reason, females with atrial fibrillation (AF) always have a CHA2DS2-VASc score of at least 1. To compare the CHA2DS2-VA (excluding female sex) and CHA2DS2-VASc scores in Korean AF patients using the Korean National Health Insurance Service database, we analyzed the risk of ischemic stroke in nonvalvular AF patients between 2013 and 2017. The predictive values of the CHA2DS2-VA and CHA2DS2-VASc scores for ischemic stroke were evaluated using the C-statistic and net reclassification improvement (NRI). The primary outcome was the occurrence of ischemic stroke. A total of 185,637 patients with AF (49.7% women) were included in this study. The mean ages were 66.5 years for females and 64.9 years for males. The incidence of ischemic stroke in male patients was similar to females (3.63%/year vs. 3.72%/year, p = 0.273, respectively). In addition, no sex difference was apparent for stroke risk in AF patients stratified by risk factor component and age group. In the C-statistic analysis, the predictive ability of the CHA2DS2-VA score for ischemic stroke was similar to the CHA2DS2-VASc score. Additionally, CHA2DS2-VA performed better for predicting ischemic stroke in AF patients with risk scores of ≥2 (AUC 0.701 vs. 0.689, z = 4.596, p < 0.001) or those aged ≥75 years (AUC 0.715 vs. 0.701, z = 4.957, p < 0.001). In Korean AF patients, female sex is not a specific risk factor that contributes to the development of ischemic stroke. The CHA2DS2-VA score, which excludes female sex, may be a more suitable risk score for guiding anticoagulation decisions in Korean AF patients.

Arrhythmias in Female Patients: Incidence, Presentation and Management

There is a growing appreciation for differences in epidemiology, treatment, and outcomes of cardiovascular conditions by sex. Historically, cardiovascular clinical trials have under-represented females, but findings have nonetheless been applied to clinical care in a sex-agnostic manner. Thus, much of the collective knowledge about sex-specific cardiovascular outcomes result from post hoc and secondary analyses. In some cases, these investigations have revealed important sex-based differences with implications for optimizing care for female patients with arrhythmias. This review explores the available evidence related to cardiac arrhythmia care among females, with emphasis on areas in which important sex differences are known or suggested. Considerations related to improving female enrollment in clinical trials as a way to establish more robust clinical evidence for the treatment of females are discussed. Areas of remaining evidence gaps are provided, and recommendations for areas of future research and specific action items are suggested. The overarching goal is to improve appreciation for sex-based differences in cardiac arrhythmia care as 1 component of a comprehensive plan to optimize arrhythmia care for all patients.

Effect of leukopenia induced by cyclophosphamide on the initial stage of arterial thrombosis in mice

INTRODUCTION

Leukocytes are found in organizing thrombi and are associated with thrombus growth. However, their role in the initial stage of thrombus formation is not well known. We investigated the role of leukocytes in the early stage of arterial thrombosis by inducing leukopenia.

METHODS

In this double-blind, randomized, placebo-controlled study, 72 Institute of Cancer Research mice were randomly treated with intraperitoneal 100 mg/kg cyclophosphamide or normal saline. The primary outcome was time to occlusion after FeCl3 treatment. We also compared thrombus size, histological composition, and association with peripheral blood cell counts between cyclophosphamide and control groups.

RESULTS

Cyclophosphamide treatment significantly decreased leukocyte counts by 82.8% compared to placebo (P < 0.001). The time to occlusion was significantly longer in the cyclophosphamide group (3.31 ± 1.59 min) than in the control group (2.30 ± 1.14 min; P = 0.003). The immunoreactivity for Ly6G-positive cells, intracellular histone H3, and released histone H3 in thrombi was significantly reduced in the cyclophosphamide group by 92.8%, 50.2%, and 34.3%, respectively. Time to occlusion had a moderate negative correlation with leukocyte count in peripheral blood (r = -0.326, P = 0.022) in the entire group.

CONCLUSIONS

Cyclophosphamide-induced leukopenia attenuated thrombus formation during the early stage of arterial thrombosis. Our findings suggest the potential role of leukocytes in the initial stage of arterial thrombosis.

Family History of Stroke is Associated with Greater Prevalence of Certain Risk Factors and Self-Reported Stroke Symptoms

OBJECTIVES

Family history of stroke increases stroke risk, however mechanisms underlying this association remain unclear. We investigated whether family history of stroke is related to increased prevalence of stroke risk factors, unhealthy behaviors and self-reported stroke symptoms in middle-aged adults.

MATERIALS AND METHODS

In a cross-sectional study conducted from November 2018 to January 2021 in 100 primary care facilities in Poland we evaluated adults aged 40-65 years (n = 2207, women 57.4%, median age 55 years) for stroke risk factors, healthy behaviors, family history of stroke, self-reported stroke symptoms and stroke knowledge using structured questionnaires. Patients were categorized based on family history of stroke defined as ≥1 first-degree relative with documented stroke.

RESULTS

Family history of stroke was reported by 571 (25.9%) individuals who were older (median age 56 vs. 54 years, p = 0.00001) and after adjustment for age more frequently suffered from hypertension (61.5% vs. 53.7%, p = 0.024) and prior transient ischemic attack (2.1% vs. 0.9%, p = 0.019), but not other risk factors. However, they were less obese (34.5% vs. 39.1%, p = 0.03). Women, but not men, with family history of stroke (n = 339, 26.8%) had greater prevalence of atrial fibrillation (7.4% vs. 3.9%, p = 0.037). Family history of stroke was associated with higher prevalence of any self-reported stroke symptom (32.9% vs. 23.2%, p < 0.00001), but not with unhealthy dietary behaviors or low level of knowledge about stroke.

CONCLUSIONS

Family history of stroke is associated with greater prevalence of certain risk factors and self-reported stroke symptoms, which indicates the need for closer surveillance of middle-aged individuals at risk.

Influence of gender on the clinical outcomes of Asian non-valvular atrial fibrillation patients: insights from the prospective multicentre COOL-AF registry

OBJECTIVE

To determine the effect of gender on clinical outcomes of Asian non-valvular atrial fibrillation patients.

DESIGN

This is a cohort study.

SETTING

27 university and regional hospitals in Thailand.

PARTICIPANTS

Patients with non-valvular atrial fibrillation.

PRIMARY AND SECONDARY OUTCOMES MEASURES

The clinical outcomes were ischaemic stroke/transient ischaemic attack (TIA), major bleeding, intracerebral haemorrhage (ICH), heart failure and death. Follow-up data were recorded every 6 months until 3 years. Differences in clinical outcomes between males and females were determined. Multivariate analysis was performed to assess the effect of gender on clinical outcomes. Survival analysis and log-rank test were performed to determine the time-dependent effect of clinical outcomes, and the difference between males and females. Effect of oral anticoagulant (OAC) on outcomes and net clinical benefit of OAC was assessed. The analysis was performed both for the whole dataset and propensity score matching with multiple imputation.

RESULTS

A total of 3402 patients (mean age: 67.4±11.3 years; 58.2% male) were included. Average follow-up duration 25.7±10.6 months (7192.6 persons-year). Rate of ischaemic stroke/TIA, major bleeding, ICH, heart failure and death were 1.43 (1.17-1.74), 2.11 (1.79-2.48), 0.70 (0.52-0.92), 3.03 (2.64-3.46) and 3.77 (3.33-4.25) per 100 person-years. Females had increased risk for ischaemic stroke/TIA and heart failure and males had increased risk for major bleeding and ICH. Ischaemic stroke/TIA risk in females and major bleeding and ICH risk in males remained even after correction for age, comorbid conditions and anticoagulation treatment. OAC reduced the risk of ischaemic stroke/TIA in males and females, and markedly increased the risk of major bleeding and ICH in males.

CONCLUSIONS

Females had a higher risk of ischaemic stroke/TIA and heart failure, and a lower risk of major bleeding and ICH compared with males. OAC reduced risk of ischaemic stroke/TIA in females, and markedly increased risk of major bleeding and ICH in males.

Sex Difference in the Risk of Dementia in Patients with Atrial Fibrillation

Atrial fibrillation (AF) is one of the risk factors for dementia. Female sex is an inconsistent risk factor for dementia after adjusting for age in the general population, and there lacks research on its impact in developing dementia in patients with AF. This paper aims to investigate whether female sex is a risk factor for dementia in AF patients. Data of patients with newly diagnosed AF between 2001–2013 were retrieved from Taiwan’s National Health Insurance Research Database. Exclusion criteria were: patients with incomplete demographic data, age < 20 years, rheumatic heart disease, hyperthyroidism, past valvular heart surgery, and a history of dementia. Propensity score matching (PSM) between sexes was performed, including comorbidities, medications and index date stratified by age. The primary outcome was a new diagnosis of dementia at follow-up. A total of 117,517 men and 156,705 women were eligible for analysis. After 1:1 PSM, both 100,065 men and women (aged 72.5 ± 12.5 years) were included for analysis. Dementia risk varied with age in women compared with men. The difference was negligible for ≤55 years (sub distribution HR (SHR) = 0.89, 95% CI 0.73–1.07), but increased between 56–65 years (SHR = 1.13, 95% CI 1.02–1.25), 66–75 years (SHR = 1.14, 95% CI 1.09–1.20), 75–85 years (SHR = 1.11, 95% CI 1.07–1.15) and >85 years (SHR 1.10, 95% CI 1.04–1.16) for females. This study establishes that female sex increases the risk of developing dementia compared to male sex in AF patients aged >56 years. However, the impact of female sex on dementia in AF patients differs between dementia types.

Women and atrial fibrillation

Atrial fibrillation (AF) remains a growing problem in the United States and worldwide, imposing a high individual and health system burden, including increased resource consumption due to repeated hospitalizations, stroke, dementia, heart failure, and death. This comprehensive review summarizes the most recent data on sex-related differences in risks associated with AF. Women with AF have increased risk of stroke and death compared to men, and possible reasons for this disparity are explored. Women also continue to have worse symptoms and quality of life, and poorer outcomes with stroke prevention, as well as with rate and rhythm control management strategies. Many current rhythm control treatment strategies for AF, including cardioversion and ablation, are used less frequently in women as compared to men, whereas women are more likely to be treated with rate control strategies or antiarrhythmic drugs. Sex differences should be considered in treating women with AF to improve outcomes and women and men should be offered the same interventions for AF. We need to improve the evidence base to understand if variation in utilization of rate and rhythm control management between men and women represents health inequities or appropriate clinical judgement.

Stroke in the adult Qatari population (Q-stroke) a hospital-based retrospective cohort study

BACKGROUND

Studies assessing the burden of stroke in Qataris are limited. We aim to study stroke in the Qatari population.

METHODS

A retrospective review was undertaken of all Qatari adults presenting with stroke to Hamad Medical Corporation over a 5-year period. Descriptive statistics were used to summarize demographic and all other clinical characteristics of the patients. The primary outcome was the incidence of stroke in the Qatari patients. Comparison was made between the sexes.

RESULTS

862 patients were included, with 58.9% being male. The average incidence of stroke over the 5-year period was 92.04 per 100,000 adult Qatari population. The mean age of the cohort was 64.3±14.4 years, (range 19-105 years). The mean age of first ever cerebrovascular event was 63.2±14.5 years. The diagnosis was ischemic stroke in (73.7%), transient ischemic attack in (13.8%), intracerebral hemorrhage (ICH) in (11.6%), subarachnoid hemorrhage in (0.7%) and (0.2%) cerebral venous sinus thrombosis. Small vessel disease was the most common cause of ischemic stroke accounting for (46.5%), followed by large artery atherosclerosis (24.5%). Hypertension (82.7%) and diabetes (71.6%) were particularly prevalent in this cohort. Females were older (65.8±14.1 vs 63.4±14.5 years), had more hypertension and diabetes and more disability or death at 90 days (p<0.05) compared to Qatari males.

CONCLUSION

Stroke occurs at a significantly lower age in Qataris compared to the western population. This study has uncovered sex differences that need to be studied further.

Impact of gender: Rivaroxaban for patients with atrial fibrillation in the XANTUS real-world prospective study

BACKGROUND

The XANTUS study (NCT01606995) demonstrated low rates of stroke and major bleeding in patients with atrial fibrillation (AF) receiving rivaroxaban in clinical practice for the prevention of thromboembolic events (N = 6784).

HYPOTHESIS

Because previous real-world studies have not reported gender-dependent responses to rivaroxaban treatment, this sub-analysis of the XANTUS study investigated the effect of gender on outcomes.

METHODS

The centrally adjudicated outcomes were compared between genders. Primary outcomes were major bleeding and all-cause death. Secondary outcomes included symptomatic thromboembolic events. Multivariable Cox regression analysis was performed to assess the effect of risk factors on outcomes between genders.

RESULTS

A total of 2765 female and 4016 male patients were included in the analysis. Baseline characteristics were generally similar. No nominally significant interaction between gender and risk factors for the study outcomes was observed. Rates of major bleeding, all-cause death and symptomatic thromboembolic events in patients with non-valvular AF receiving rivaroxaban for stroke prevention were similar in men and women; no significant differences in risk factors for these outcomes were observed between genders.

CONCLUSIONS

Further research is needed to better characterize the relative importance of different risk factors on outcomes in men vs women and to determine whether gender differences exist in patients treated with non-vitamin K antagonist oral anticoagulants.

Influence of sex on long-term prognosis in patients with atrial fibrillation treated with oral anticoagulants. Results from the prospective, nationwide FANTASIIA study

BACKGROUND

While many risk factors for Atrial Fibrillation (AF) have been identified, there are important differences in their relative impact between sexes. The aim of our study was to investigate the influence of sex as a long-term predictor of adverse events in "real world" AF patients treated with direct oral anticoagulants.

METHODS

The FANTASIIA registry is a prospective, national and multicentric study including outpatients with anticoagulated AF patients. Baseline characteristics and adverse events at 3 years of follow-up were collected and classified by sex. Cox multivariate analysis was performed to investigate the role of sex in major events and composite outcomes.

RESULTS

A total of 1956 patients were included in the study. 43.9% of them were women, with a mean age of 73.8 ± 9.4 years (women were older 76.5 ± 7.9 vs 71.7 ± 10.1, p<0.001). Women had higher rate of cardiovascular risk factors and higher mean of CHA₂DS₂-VASc (4.4 ± 1.4 vs 3.7 ± 1.6, p<0.001) and HAS-BLED (2.1 ± 1.0 vs 1.9 ± 1.1, p<0.001) than men. After 3 years of follow-up, rates of major events were similar in both groups with limit difference for all-cause mortality (4.4%/year in women vs 5.6%/year in men; p = 0.056). However, all the composite events were more frequent in women. We observed in the non-adjusted adverse events lower rate of all-cause mortality (HR 0.62, 95%CI 0.47-0.81; p<0.001), composite 1 outcomes (HR 0.80, 95%CI 0.65-0.98; p = 0.029) and composite 2 (HR 0.77, 95%CI 0.64-0.94; p = 0.010) in women compared with men. In multivariate Cox regression analysis observed that female sex was an independently protector factor for all-cause mortality and for the composite outcomes 1 and 2.

CONCLUSIONS

In this "real world" study of anticoagulated AF patients, women could have a protective role against development of adverse events, mainly on all-cause mortality and combined events.

Sex Differences in Disease Profiles, Management, and Outcomes Among People with Atrial Fibrillation After Ischemic Stroke: Aggregated and Individual Participant Data Meta-Analyses

Objectives: To examine sex differences in disease profiles, management, and survival at 1 and 5 years after ischemic stroke (IS) among people with atrial fibrillation (AF).

Methods: We performed a systematic literature search of reports of AF at IS onset according to sex. We undertook an individual participant data meta-analysis (IPDMA) of nine population-based stroke incidence studies conducted in Australasia, Europe, and South America (1993–2014). Poisson regression was used to estimate women:men mortality rate ratios (MRRs). Study-specific MRRs were combined using random effects meta-analysis.

Results: In our meta-analysis based on aggregated data from 101 studies, the pooled AF prevalence was 23% (95% confidence interval [CI]: 22%–25%) in women and 17% (15%–18%) in men. Our IPDMA is of 1,862 IS-AF cases, with women (79.2 ± 9.1, years) being older than men (76.5 ± 9.5, years). Crude pooled mortality rate was greater for women than for men (1-year MRR 1.24; 1.01–1.51; 5-year 1.12; 1.03–1.22). However, the sex difference was greatly attenuated after accounting for age, prestroke function, and stroke severity (1-year 1.09; 0.97–1.22; 5-year 0.98; 0.84–1.16). Women were less likely to have anticoagulant prescription at discharge (odds ratio [OR] 0.94; 95% CI: 0.89–0.98) than men when pooling IPDMA and aggregated data.

Conclusions: AF was more prevalent after IS among women than among men. Among IS-AF cases, women were less likely to receive anticoagulant agents at discharge; however, greater mortality rate in women was mostly attributable to prestroke factors. Further information needs to be collected in population-based studies to understand the reasons for lower treatment of AF in women.

Female Sex as a Thromboembolic Risk Factor in the Era of Nonvitamin K Antagonist Oral Anticoagulants

Sex-specific differences have been definitively demonstrated in cardiovascular (CV) diseases. These differences can also impact on the effects of CV therapies. Female sex is recognized as an independent predictor of thromboembolic risk, particularly in older patients. Most of strokes are due to atrial fibrillation (AF). Women affected by AF have higher stroke risk compared to men. The introduction of novel oral anticoagulants (NOACs) for long-term anticoagulation completely changed the anticoagulant therapeutic approach and follow-up of patients affected by nonvalvular atrial fibrillation (NVAF). CHA2DS2-VASc stroke risk scoring in use in the current international guidelines attributes 1 point to “female sex”. Besides, no anticoagulation is indicated for AF female patients without other risk factors. Interestingly, NOACs seem to normalize the differences between males and females both in terms of safety and efficacy, whereas residual higher stroke risk and systemic embolism persist in AF women treated with vitamin K antagonist anticoagulants VKA with optimal time in therapeutic range. Based on the CHA2DS2-VASc score, NOACs represent the preferred choice in NVAF patients. Moreover, complete evaluation of apparently lower risk factor along with concomitant clinical conditions in AF patients appears mandatory, particularly for female patients, in order to achieve the most appropriate anticoagulant treatment, either in male or in female patients. The present review was performed to review sex differences in AF-related thromboembolic risk reported in the literature and possibly highlight current knowledge gaps in prevention and management that need further research.

Sex-related differences in prevalence, treatment and outcomes in patients with atrial fibrillation

To analyze sex-related differences about AF prevalence, use of OAC and outcomes focusing on the older age classes. We used administrative data of the Lombardy Region, describing period prevalence, use of OAC and outcomes from 2002 to 2014 for all patients diagnosed with AF. AF prevalence over the 2002-2014 period was higher in males than in females (2.7% vs. 2.1%, p < 0.001), increasing with age. From 2003 to 2014, not treated AF patients decreased mostly in males (from 40.3 to 33.7% with respect to 43.7-39.8% in females). Age-stratified adjusted logistic regression analysis found that females were more likely treated with OAC when < 65 years in 2003 (OR 1.51, 95% CI 1.35-1.69) and in 2014 (OR 1.32, 95% CI 1.13-1.53); contrariwise, were less likely treated with OAC when age ≥ 75 years, in 2003 (OR 0.92, 95% CI 0.86-0.98) and in 2014 (OR 0.77, 95% CI 0.72-0.81).Adjusted Cox regression analysis confirmed that female AF patients had a higher risk of stroke (HR 1.18, 95% CI 1.14-1.21) and a lower risk of major bleeding (HR 0.83, 95% CI 0.80-0.86), while, had a lower risk for all-cause death (HR 0.82, 95% CI 0.80-0.83). AF prevalence was higher in male than in female patients, while thromboembolic risk was higher in female. Older female patients were under-treated with OAC particularly in recent years. Over long-term follow-up, female had a higher risk of stroke and a lower risk of major bleeding and all-cause death.

The Tasmanian Atrial Fibrillation Study (TAFS): Differences in Stroke Prevention According to Sex

Background: There are limited Australian data on sex differences in oral anticoagulant (OAC) prescribing in atrial fibrillation (AF) and ongoing debate regarding the optimal approach to stroke risk assessment and OAC prescribing in female patients with AF. Objective: The purpose of this study was to investigate sex differences in the prescribing of OACs in patients with AF stratified by stroke risk and in the rate of adverse outcomes. Methods: A retrospective analysis of patients admitted to the Royal Hobart Hospital (Tasmania, Australia) with nonvalvular AF between January 2011 and July 2015 was conducted. Rates of antithrombotic prescribing according to sex and stroke risk were assessed along with a multivariate analysis for predictors of OAC prescribing. Rates of thromboembolism, bleeding, and all-cause mortality were assessed according to sex. Results: A total of 2090 patients were included (44.7% female). Women with a CHA2DS2-VA score ≥2 were less likely to receive an OAC compared with men (56.7% vs 62.2%, P = 0.023). Female sex was an independent negative predictor of OAC prescribing (adjusted odds ratio = 0.83; 95% CI = 0.69-0.99; P = 0.041). There were no sex differences in the incidence rates of thromboembolism, bleeding, or all-cause mortality in patients newly commenced on antithrombotic therapy. Conclusion and Relevance: Female patients with a high stroke risk were less likely to receive guideline-recommended treatment. This study provides new information on prescribing trends within the Australian setting and highlights the opportunity to improve the management of female patients with AF and 1 or more additional stroke risk factors.

Sex Differences in Severity of Stroke in the INSTRUCT Study: a Meta-Analysis of Individual Participant Data

Background

Women have worse outcomes after stroke than men, and this may be partly explained by stroke severity. We examined factors contributing to sex differences in severity of acute stroke assessed by the National Institutes of Health Stroke Scale.

Methods and Results

We pooled individual participant data with National Institutes of Health Stroke Scale assessment (N=6343) from 8 population‐based stroke incidence studies (1996–2014), forming part of INSTRUCT (International Stroke Outcomes Study). Information on sociodemographics, stroke‐related clinical factors, comorbidities, and pre‐stroke function were obtained. Within each study, relative risk regression using log‐binominal modeling was used to estimate the female:male relative risk (RR) of more severe stroke (National Institutes of Health Stroke Scale>7) stratified by stroke type (ischemic stroke and intracerebral hemorrhage). Study‐specific unadjusted and adjusted RRs, controlling for confounding variables, were pooled using random‐effects meta‐analysis. National Institutes of Health Stroke Scale data were recorded in 5326 (96%) of 5570 cases with ischemic stroke and 773 (90%) of 855 participants with intracerebral hemorrhage. The pooled unadjusted female:male RR for severe ischemic stroke was 1.35 (95% CI 1.24–1.46). The sex difference in severity was attenuated after adjustment for age, pre‐stroke dependency, and atrial fibrillation but remained statistically significant (pooled RR_adjusted 1.20, 95% CI 1.10–1.30). There was no sex difference in severity for intracerebral hemorrhage (RR_crude 1.08, 95% CI 0.97–1.21; RR_adjusted 1.08, 95% CI 0.96–1.20).

Conclusions

Although women presented with more severe ischemic stroke than men, much although not all of the difference was explained by pre‐stroke factors. Sex differences could potentially be ameliorated by strategies to improve pre‐stroke health in the elderly, the majority of whom are women. Further research on the potential biological origin of sex differences in stroke severity may also be warranted.

Left Atrial Phasic Function in Patients with Hypertension and Recurrent Atrial Fibrillation: Gender Differences of the Relationship with Diastolic Dysfunction and Central Aortic Pressure

Aim. To evaluate gender-related differences of left atrial (LA) phasic function and structural remodeling in conjunction with the parameters of left ventricular (LV) diastolic dysfunction and central aortic pressure in patients with hypertension and recurrent atrial fibrillation (AF).

Material and methods. The comparative study included 30 men and 37 women with non-valvular AF, hypertension and LV hypertrophy. Conventional echocardiographic measures were extended with LA measures, including its volume in three phases, LAemptying fraction (LAEF), passive and active ejection fraction. The parameters of central aortic pressure were estimated by applanation tonometry method.

Results. No difference was observed between LA and LV structural parameters in men and women. However, in women LAEF (39 [28;50] vs 50 [42;55]%; p=0.02) and E/E’(9.7 [7.8;12] vs 7.1 [5.6;8.6]; p=0.001) were worse than in men. Active LA ejection fraction was higher in women (31 [21;42] vs 24 [19;31]%; p=0.04), whereas passive one – in men (12 [10;14] vs 33 [23;38]%; p<0.001), respectively. Men and women had comparable heart rate (HR), central and peripheral systolic and diastolic pressure, pulse wave velocity (PWV), but women had higher augmentation index (AI) values [33 [28;39] vs 23 [21;28]%; p<0.001], even adjusted by HR (AI 75) (34 [27;39] vs 26 [20;29]%; p<0.001). Only in men PWV weakly correlated with AI 75 (r=0.44; p=0.02 versus r=-0.11; p=0.51, respectively for men and women; intergroup differences: z=2.26; p=0.012). In a multivariate regression analysis in men LAEF was significantly associated with height, weight, E’, E/E’ and glomerular filtration rate (GFR), whereas in women – with E’ and AI 75.

Conclusion. Patients of different genders with recurrent AF and hypertension have comparable LA structuralremodeling. However, women characterized by a more pronounced decrease in LAEF and impaired LV diastolic function than men. In women as distinct from men LV filling is predominantly due to LA systole. In a multivariate regression analysis in men LAEF was significantly associated with height, weight, E’, E/E’ and GFR, whereas in women – with E’ and AI 75. 

Identification of Markers Associated With Development of Stroke in "Clinically Low-Risk" Atrial Fibrillation Patients

Background

Stroke and thromboembolic events may still occur in “clinically low‐risk” atrial fibrillation (AF) patients as categorized by CHA₂DS₂‐VASc score. Our aim was to assess the proportion of “clinically low‐risk” patients using a nongender CHA₂DS₂‐VASc (ie, CHA₂DS₂‐VA) score of 0 to 1 among patients who experienced AF‐associated stroke and to identify markers associated with stroke in “clinically low‐risk” patients.

Methods and Results

We retrospectively recruited nonvalvular AF patients who experienced embolic stroke between 2013 and 2016 from 9 institutes in Korea. AF patients with CHA₂DS₂‐VA score of 0 to 1 at the time of stroke were analyzed and compared with “clinically low‐risk” AF patients without stroke. A total of 3033 subjects with AF‐associated stroke were recruited. Of these, 583 patients (19.2%) had CHA₂DS₂‐VA score of 0 to 1. On multivariate analysis, age (≥60 years), N‐terminal pro B‐type natriuretic peptide (≥300 pg/mL), creatinine clearance (<50 mL/min), and left atrial dimension (≥45 mm) were independently associated with stroke. With the combined application of these 4 factors (collectively, ABCD score) to the “clinically low‐risk” patients, the c‐index was 0.858 (95% CI 0.838–0.877; P<0.001).

Conclusions

The present study suggests a new insight into how additional use of markers can further refine stroke risk differentiation among AF patients initially classified as “clinically low‐risk.”

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT03147911.

Gender Differences in Arrhythmias: Focused on Atrial Fibrillation

There are significant differences in clinical presentation and treatment of atrial fibrillation (AF) between women and men. The primary goal of AF management is to restore sinus rhythm and to prevent various complications, including stroke and heart failure. In many areas of AF, such as prevalence, clinical manifestations, morbidity, risk factors, pathophysiology, treatment strategies, and complications, gender-specific variability is observed and needs to be further addressed by large-scale population researches or randomized clinical trials, which help to promote the customization of AF treatment programs, hence to maximize the success rate of AF therapy in both sexes. This review highlights our current understanding of these gender differences in AF and how these differences affect treatment decisions on AF.

National trends in hospital admission, case fatality, and sex differences in atrial fibrillation-related strokes

BACKGROUND AND AIM

Atrial fibrillation is associated with increased risk of ischemic stroke and its global prevalence is increasing. We aimed to describe the contemporary temporal trends in hospital admissions, case fatality rate, as well as sex differences in atrial fibrillation-related stroke in Canada.

METHODS

We conducted a retrospective cohort study using Canadian national administrative data to identify admissions to hospital for stroke with comorbid atrial fibrillation between 1 April 2007 and 31 March 2016. We determined temporal trends in the crude and the age- and sex-standardized admission and case fatality rates. We also evaluated for any sex differences in these outcomes.

RESULTS

There were 222,100 admissions to hospital for ischemic (n = 182,990) or hemorrhagic (n = 39,110) stroke. Comorbid atrial fibrillation was present in 20.2% of admissions for ischemic strokes and 10.1% for hemorrhagic strokes. Over the study period, the age-sex adjusted proportion of admissions with atrial fibrillation increased from 16.3% to 20.5% (p = 0.02) for ischemic stroke and was stable for hemorrhagic stroke. In-hospital case fatality rate decreased for ischemic stroke with and without comorbid atrial fibrillation. Women aged 65 years and older with ischemic stroke were more likely to have comorbid atrial fibrillation compared to men, while this association was reversed in younger women. There were no sex differences in the case fatality rate for people with atrial fibrillation-related ischemic stroke.

CONCLUSION

Atrial fibrillation is present in an increasing proportion of people hospitalized in Canada with ischemic stroke and disproportionately affects older women. Renewed focus is needed on atrial fibrillation-related stroke prevention with particular attention to sex disparities.

The risk of stroke and associated risk factors in a health examination population: A cross-sectional study

Health examination is an important method for early detection of people with different risk of stroke. This study estimates the risk of stroke and identify risk factors for people who underwent health examinations at the Health Examination Center at West China Hospital, Sichuan University from July 2014 to February 2018.A total of 31,464 people were recruited in this study and divided into 3 groups (low risk, moderate risk, and high risk) according to risk of stroke. We explored possible factors associated with the risk of stroke by using multivariable stepwise logistic regression analysis.Among the participants, 17,959 were at low risk, 11,825 were at moderate risk, and 1680 were at high risk. Age, smoking, alcohol consumption, body mass index, uric acid, diastolic pressure, systolic pressure, triglycerides, low-density lipoprotein cholesterol, glucose, and brachial-ankle pulse wave velocity (baPWV) were independent significant risk factors for stroke, whereas high-density lipoprotein cholesterol was an independent protective factor for stroke. Interestingly, with increasing age, the percentage of people at moderate or high risk of stroke was increased. The percentages of people at moderate and high risk of stroke were also increased with respect to the stages of baPWV.This study showed that >40% of the participants were at moderate or high risk of stroke, especially the older participants. Several factors were related to the risk of stroke, especially baPWV. Some preventive action may be adopted early, and more attention can be paid to the health examination population.

Female sex as a risk factor for ischaemic stroke varies with age in patients with atrial fibrillation

Objectives

Female sex is an inconsistent ischaemic stroke risk factor in patients with atrial fibrillation (AF). We hypothesised that the ischaemic stroke risk varies with age among women compared with men.

Methods

We retrieved the patients with newly diagnosed AF during 2001–2013 from Taiwan’s National Health Insurance Research Database. Patients with missing information, age <20 years, history of valvular heart disease and surgery, rheumatic heart disease, hyperthyroidism or anticoagulation and/or antiplatelet use were excluded. Propensity score matching (PSM) included patient comorbidities, medications and index date stratified by age and sex groups. Primary outcome was defined as ischaemic stroke at follow-up.

Results

After exclusion criteria, 87 369 men and 71 853 women remained for analysis (aged 73.1±14.4 years). After 1:1 PSM, we included 59 583 men (aged 73.5±13.7 years) and 59 583 women (aged 73.4±13.8 years) for analysis. We also stratified patients by age. The ischaemic stroke risk varied with age in women compared with men: lower in the ≤55 years (subdistribution HR (SHR)=0.75, 95% CI 0.62 to 0.90) and 56–65 years (SHR=0.87, 95% CI 0.78 to 0.98) groups, neutral in the 66–75 years group (SHR=1.01, 95% CI 0.94 to 1.08) and adverse in the >75 years group (SHR=1.14, 95% CI 1.09 to 1.19).

Conclusions

The female/male ischaemic stroke risk ratio varied with age. Only women aged >75 years had a higher risk, whereas women aged <65 years had a lower risk compared with men. These findings challenge the ‘sex category’ component of the CHA2DS2-VASc score, used to make decision regarding anticoagulation treatment in AF patients.

Women Who Have Ischemic Strokes Have a Higher Burden of Left Atrial Fibrosis Than Men

Background and Purpose- Women with atrial fibrillation (AF) have a higher risk of stroke than men who have AF. Atrial fibrosis is a marker of atrial disease that precedes the appearance of AF increasing the risk of ischemic stroke. We aimed to determine whether female sex is independently associated with left atrial fibrosis in stroke patients. Methods- We prospectively included a consecutive sample of ischemic stroke patients aged over 50 years of age. Late gadolinium enhancement cardiac magnetic resonance imaging was performed to quantify the severity of left atrial fibrosis and the wall pattern of its distribution. A multivariable linear regression analysis was performed to determine whether female sex was independently associated with left atrial fibrosis after adjusting for potential confounders namely AF and age. Results- One hundred twenty-four patients were deemed eligible; 117 patients were included (7 were excluded because of cardiomyopathy identified by cardiac magnetic resonance imaging). All had usable cardiac magnetic resonance imaging data. Fifty-three patients (45.3%) were women. Women were older and were less frequently treated with angiotensin-converting-enzyme inhibitors. Ninety-one patients had any degree of atrial fibrosis. Women had a higher percentage of atrial fibrosis than men-median (interquartile range)-18% (17) versus 10% (20). In a multivariable linear regression model adjusted for demographics, medications, AF, comorbidities, and cardiac parameters, female sex was found to be independently associated with left atrial fibrosis. Women were found to have more 4.70% of left atrial fibrosis than men (95% CI, 0.70-8.71%; P=0.02) after controlling for confounders. Conclusions- Female sex was found to be independently associated with left atrial fibrosis after controlling for confounders such as AF and age. Further studies are needed to understand if this contributes to the increased stroke risk related to AF in women compared with men.

Risk of ischemic stroke and utility of CHA2 DS2 -VASc score in women and men with atrial fibrillation

Background

The magnitude of increased risk of stroke in women with atrial fibrillation (AF) remains uncertain.

Hypothesis

We investigated the risk of ischemic stroke and death in women and men with AF, and the risk associated with individual non‐sex CHA₂DS₂‐VASc risk factors.

Methods

Retrospective cohort study of 231 077 (48.1% women) nonselected patients with AF not receiving oral anticoagulation from 2006 to 2014. Data from cross‐linked national Swedish registers. The outcome was the first occurrence of ischemic stroke or death. Median age was 82 and 75 years in women and men, respectively. Mean follow‐up was 2.5 years.

Results

Hazard ratios, adjusted for non‐sex CHA₂DS₂‐VASc risk factors, for women vs men were 1.53, 95% CI: 1.49‐1.58 for ischemic stroke and 1.24, 95% CI: 1.22‐1.26 for death, respectively. When divided into age groups the differences in ischemic stroke rates between women and men were attenuated. In patients with only one non‐sex CHA₂DS₂‐VASc risk factor allotted 1 point, ischemic stroke rates per 100 person‐years were 1.22 in women (n = 9838) and 1.02 in men (n = 15 609), respectively, P < .006. In both women and men, age of 65 to 74 years was associated with higher ischemic stroke risk compared to other non‐sex CHA₂DS₂‐VASc risk factors allotted 1 point.

Conclusions

The risk of ischemic stroke was 1.5‐fold higher in women compared to men but this association appears to be the result of confounding by age. In the low risk end, the CHA₂DS₂‐VASc risk score underestimates the ischemic stroke risk conferred by age 65 to 74 years, while it overestimates the risk conferred by female sex.

Is anticoagulant therapy always indicated in "medium-risk" patients with first diagnosed atrial fibrillation? Insights from a real world, 10-year observational study

BACKGROUND

The choice of antithrombotic prophylaxis in the so-called "medium-risk" patients (i.e., CHA₂DS₂-VASc score = 1 in males or 2 in females) is one of the major enigmatic issues in clinical management of atrial fibrillation (AF).

METHODS

We retrospectively evaluated 30-day and 1-year thromboembolic events in all consecutive medium-risk patients visited for first diagnosed AF in the local Emergency Department during a 10-year period. The main aim was to establish whether anticoagulant or antiplatelet therapy was effective to lower the thromboembolic risk in patients receiving these drugs. Bleeding events, related to anticoagulant or antiplatelet therapy, was defined as secondary end point.

RESULTS

The final study population consisted of 6389 (3640 males and 2749 females) patients for whom a complete dataset regarding targeted follow-up was available. Patients were then subdivided into two subgroups, according to performance of cardioversion and spontaneous sinus rhythm restoring. In both genders, no significant difference in thromboembolic or bleeding events was noted between patients who underwent cardioversion and were discharged with oral anticoagulant therapy or antiplatelet treatment versus those who were not treated with antithrombotic drugs. Moreover, no difference was also observed in thromboembolic or hemorrhagic event rate between low risk and "medium-risk" patients.

CONCLUSIONS

The results of this study suggest that anticoagulant or antiplatelet therapy would not produce clinical benefits in "medium-risk" AF patients.