Risk factors for ischemic stroke in patients with non-valvular atrial fibrillation and therapeutic international normalized ratio range

Prevalence and Risk Factors of Stroke in Patients with Nonvalvular Atrial Fibrillation: A Case-Control Study

OBJECTIVE

To analyze the prevalence and influencing factors of stroke in patients with nonvalvular atrial fibrillation (SIPWNVAF), and to provide a reference basis for the prevention and control of stroke.

METHODS

Data were obtained from the China National Stroke Screening Survey. From January 2016 to December 2023, a total of 15,471 permanent residents aged ≥40 years in Yinchuan were screened. Patients with nonvalvular atrial fibrillation who had their first stroke were selected as the stroke group (86 patients), and patients with nonvalvular atrial fibrillation who had never had a stroke as the control group (477 patients).

RESULTS

In 563 residents, the crude prevalence of SIPWNVAF was 15.28%, and the standardized prevalence was 9.33%. The multivariable logistic regression analysis revealed that age (odds ratio [OR]: 1.42; 95% confidence interval [CI]: 1.17-1.71), smoking (OR: 2.10; 95% CI: 1.46-3.01), drinking (OR: 2.00; 95% CI: 1.28-3.13), lack of exercise (OR: 2.18; 95% CI: 1.18-4.03), family history of stroke (OR: 4.39; 95% CI: 1.82-10.57), hypertension (OR: 1.94; 95% CI: 1.03-3.63), diabetes (OR: 3.10; 95% CI: 1.37-7.05), dyslipidemia (OR: 2.15; 95% CI: 1.16-3.99), homocysteine ≥15 μmol/L (OR: 2.13; 95% CI: 1.14-3.97), and carotid atherosclerosis (OR: 2.86; 95% CI: 1.53-5.37) were independent risk factors, but educational level (OR: 0.31; 95% CI: 0.17-0.58) was a protective factor for SIPWNVAF.

CONCLUSIONS

The stroke group is significantly more burdened by other independent common risk factors for stroke.

Limitations in Contemporary Pharmacological Stroke Prevention Therapies in Atrial Fibrillation: A Descriptive Literature Review

The most common arrhythmia, atrial fibrillation (AF), increases with age and is associated with a 5-fold increased risk of stroke. Although lifelong oral anticoagulation (OAC) is strongly recommended for stroke prevention in patients with AF and CHA2DS2-VASc ≥ 2 only 50-60% of patients in Western countries belonging to this group are treated with oral anticoagulants, and less than half of these adhere to therapy over time. Before 2010, the numerous limitations associated with vitamin K antagonists (VKAs) were considered to be the reason behind OAC underuse; however, the approval of direct oral anticoagulants (DOACs) that require once- or twice-daily intake, no regular blood tests and fewer drug-food interactions has resulted in only modest improvements in OAC use and adherence.

Evaluation of Blood Biomarkers and Parameters for the Prediction of Stroke Survivors' Functional Outcome upon Discharge Utilizing Explainable Machine Learning

Despite therapeutic advancements, stroke remains a leading cause of death and long-term disability. The quality of current stroke prognostic models varies considerably, whereas prediction models of post-stroke disability and mortality are restricted by the sample size, the range of clinical and risk factors and the clinical applicability in general. Accurate prognostication can ease post-stroke discharge planning and help healthcare practitioners individualize aggressive treatment or palliative care, based on projected life expectancy and clinical course. In this study, we aimed to develop an explainable machine learning methodology to predict functional outcomes of stroke patients at discharge, using the Modified Rankin Scale (mRS) as a binary classification problem. We identified 35 parameters from the admission, the first 72 h, as well as the medical history of stroke patients, and used them to train the model. We divided the patients into two classes in two approaches: "Independent" vs. "Non-Independent" and "Non-Disability" vs. "Disability". Using various classifiers, we found that the best models in both approaches had an upward trend, with respect to the selected biomarkers, and achieved a maximum accuracy of 88.57% and 89.29%, respectively. The common features in both approaches included: age, hemispheric stroke localization, stroke localization based on blood supply, development of respiratory infection, National Institutes of Health Stroke Scale (NIHSS) upon admission and systolic blood pressure levels upon admission. Intubation and C-reactive protein (CRP) levels upon admission are additional features for the first approach and Erythrocyte Sedimentation Rate (ESR) levels upon admission for the second. Our results suggest that the said factors may be important predictors of functional outcomes in stroke patients.

Prothrombin Time-International Normalized Ratio Predicts the Outcome of Atrial Fibrillation Patients Taking Rivaroxaban

Background: Although direct oral anticoagulants (DOACs) for patients with atrial fibrillation (AF) are considered to be safe, over or under anticoagulation and increased bleeding or thromboembolic risk are still considered individually. We aimed to investigate whether there is an association between prothrombin time and international normalized ratio (PT-INR) or activated partial thromboplastin time (aPTT) ratio, and the risks of ischemic stroke/systemic embolism (IS/SE) and major bleeding among AF patients taking rivaroxaban or dabigatran. Methods: This multi-center cohort study in Taiwan included 3192 AF patients taking rivaroxaban and 958 patients taking dabigatran for stroke prevention where data about PT-INR and aPTT were available. Results: For patients treated with rivaroxaban, a higher INR level was not associated with a higher risk of major bleeding compared to an INR level < 1.1. The risk of IS/SE was lower for patients having an INR ≥ 1.5 compared to those with an INR < 1.1 (aHR:0.57; [95%CI: 0.37−0.87]; p = 0.01). On-label dosing of rivaroxaban and use of digoxin were independent factors associated with an INR ≥ 1.5 after taking rivaroxaban. For patients taking dabigatran, a higher aPTT ratio was not associated with a higher risk of major bleeding. The risk of IS/SE was lower for patients having an aPTT ratio of 1.1−1.2 and 1.3−1.4 than those with an aPTT ratio < 1.1. Conclusions: In AF patients, rivaroxaban with an INR ≥ 1.5 was associated with a lower risk of IS/SE. PT-INR or aPTT ratios were not associated with bleeding events for rivaroxaban or dabigatran. INR may help predict the outcome of AF patients who take rivaroxaban.

Admission Severity of Atrial-Fibrillation-Related Acute Ischemic Stroke in Patients under Anticoagulation Treatment: A Systematic Review and Meta-Analysis

Background: In non-valvular-associated atrial fibrillation (AF), direct oral anticoagulants (DOAC) are as effective as vitamin K antagonists (VKA) for the prevention of acute ischemic stroke (AIS). DOAC are associated with decreased risk and severity of intracranial hemorrhage. It is unknown if different pre-admission anticoagulants impact the prognosis of AF related AIS (AF-AIS). We sought to analyze the literature to assess the association between pre-admission anticoagulation (VKA or DOAC) and admission severity of AF-AIS. Methods: A Systematic literature search (PubMed and ScienceDirect) between January 2011 to April 2021 was undertaken to identify studies describing the outcome of AF-AIS. Results: A total of 128 articles were identified. Of 9493 patients, 1767 were on DOAC, 919 were on therapeutical VKA, 792 were on non-therapeutical VKA and 6015 were not anticoagulated. In comparison to patients without anticoagulation, patients with therapeutical VKA and under DOAC presented with less severe stroke (MD −1.69; 95% CI [−2.71, −0.66], p = 0.001 and MD −2.96; 95% Cl [−3.75, −2.18], p < 0.00001, respectively). Patients with non-therapeutical VKA presented with more severe stroke (MD 1.28; 95% Cl [0.45, 2.12], p = 0.003). Conclusions: In AF-AIS, patients under therapeutical VKA or DOAC have reduced stroke severity on admission in comparison to patients without any anticoagulation, with higher magnitude of protection for DOAC.

Left Atrial Strain Helps Identifying the Cardioembolic Risk in Transient Ischemic Attacks Patients with Silent Paroxysmal Atrial Fibrillation

Purpose

Patients with transient ischemic attacks often present asymptomatic and paroxysmal atrial fibrillation. Since atrial fibrillation initiates in the atria, we aimed to identify whether the abnormalities in left atrial structure and function could identify the cardioembolic etiology of the transient ischemic attacks in patients at sinus rhythm.

Patients and Methods

A total of 190 patients over 50 years old with sinus rhythm discharged after a transient ischemic attack were included in the study and divided into two groups according to the presence (group I) or absence (group II) of documented paroxysmal atrial fibrillation. The documentation of paroxysmal atrial fibrillation was based on the examination of medical registers. Cardiac ultrasound assessment was performed at a minimum of 14 days after the onset of the transient ischemic attack, to avoid assessment of atrial stunning.

Results

The group I patients were older, more frequent women, with a history of stroke or transient ischemic attack and a higher CHA2DS2-VASc score. They also presented larger left atrial volumes, lower left atrial emptying fraction, and significantly impaired left atrial deformation patterns. Multivariate logistic regression identified three variables that were independently associated with paroxysmal atrial fibrillation: age, left atrial reservoir strain, and left atrial emptying fraction (P < 0.0001). The cut-off levels for the variables were age > 55 years, reservoir strain < −17%, and emptying fraction < 51%.

Conclusion

The present study demonstrates that the LA strain is independently associated with paroxysmal atrial fibrillation in transient ischemic attack patients and might be of great help in identifying their cardioembolic etiology and preventing subsequent strokes by the initiation of anticoagulant therapy.

The Effect of Transcranial Direct Current Stimulation and Functional Electrical Stimulation on the Lower Limb Function of Stroke Patients

Objective: This study aimed to research the effect of transcranial direct current stimulation (tDCS) and functional electrical stimulation (FES) on the lower limb function of post-convalescent stroke patients.

Methods: A total of 122 patients in the stroke recovery stage who suffered from leg dysfunction were randomly divided into two groups: a tDCS group (n = 61) and a FES group (n = 61). All patients received same routine rehabilitation and equal treatment quality, the tDCS group was treated with tDCS, while the FES group received FES. The lower limb Fugl-Meyer assessment (FMA), modified Barthel index (MBI), functional ambulatory category (FAC), and somatosensory evoked potential (SEP) were used to assess the patients at three different stages: prior to treatment, 4 weeks after treatment, and 8 weeks after treatment.

Results: The assessment scores for FMA, MBI, and FAC for the lower extremities after treatment (P > 0.05) were compared with those before treatment. The FMA, MBI, and FAC scores of the tDCS group were significantly higher than those of the FES group in all three stages (P < 0.05). The FMA, MBI, and FAC assessment scores of both groups were significantly higher after 4 weeks of treatment than that before treatment, and the scores after 8 weeks of treatment were significantly higher than those after 4 weeks after treatment (P < 0.05). The P40, N45 latencies decreased and the P40, N45 amplitudes increased, but there was no significant difference before treatment and after treatment (P >0.05), and there was no significant difference of the tDCS and FES groups before treatment and after treatment.

Conclusion: In conclusion, FMA, MBI, and FAC indicate that both tDCS and FES can significantly promote the recovery of a patient’s leg motor function and tDCS is more effective than FES in the stroke recovery stage. The application value of SEP in stroke patients remains to be further studied.

Pre-Stroke Statin Therapy Improves In-Hospital Prognosis Following Acute Ischemic Stroke Associated with Well-Controlled Nonvalvular Atrial Fibrillation

Many studies have confirmed the positive effect of statins in the secondary prevention of ischemic stroke. Although several studies have concluded that statins may also be beneficial in patients with atrial fibrillation-related stroke, the results of those studies are inconclusive. Therefore, the aim of this study was to analyze the effect of pre-stroke statin therapy on atrial fibrillation-related stroke among patients with a well-controlled atrial fibrillation. This retrospective multicenter analysis comprised 2309 patients with acute stroke, with a total of 533 patients meeting the inclusion criteria. The results showed a significantly lower neurological deficit on the National Institutes of Health Stroke Scale at hospital admission and discharge in the group of atrial fibrillation-related stroke patients who took statins before hospitalization compared with those who did not (p < 0.001). In addition, in-hospital mortality was significantly higher in the atrial fibrillation-related stroke patients not taking statins before hospitalization than in those who did (p < 0.001). Based on the results of our previous research and this current study, we postulate that the addition of a statin to the oral anticoagulants may be helpful in the primary prevention of atrial fibrillation-related stroke.

Atrial fibrillation risk factors in patients with ischemic stroke

INTRODUCTION

Atrial fibrillation (AF) is the most common heart arrhythmia. The condition is known to increase the risk of ischemic stroke (IS). Classical risk factors for the development of AF include advanced age, hypertension, diabetes mellitus, coronary heart disease and lipid metabolism disorders. Importantly, these are also recognized risk factors for ischemic stroke. Therefore, the purpose of this study was to investigate AF risk factors in patients with IS.

MATERIAL AND METHODS

This is single-centre retrospective study which included 696 patients with acute ischemic stroke and nonvalvular atrial fibrillation and 1678 patients with acute ischemic stroke without atrial fibrillation.

RESULTS

In this study we found - based on a univariable and multivariable logistic regression model - that compared to the patients with IS without AF, the group of patients which suffered from IS with nonvalvular atrial fibrillation (NVAF) had a higher proportion of patients who smoked cigarettes (OR = 15.742, p < 0.01; OR = 41.1, p < 0.01), had hypertension (OR = 5.161, p < 0.01; OR = 5.666, p < 0.01), history of previous stroke (OR = 3.951, p < 0.01; OR = 4.792, p < 0.01), dyslipidemia (OR = 2.312, p < 0.01; OR = 1.592, p < 0.01), coronary heart disease (OR = 2.306, p < 0.01; OR = 1.988, p < 0.01), a greater proportion of female patients (OR = 1.717, p < 0.01; OR = 2.095, p < 0.01), higher incidence of diabetes mellitus (OR = 1.341, p < 0.01; OR = 1.261, p = 0.106) and more patients in old age (OR = 1.084, p < 0.01; OR = 1.101, p < 0.01).

CONCLUSIONS

Our study demonstrates a need for thorough and systematic monitoring of post-ischemic stroke patients in whom AF has not been detected and who display other important risk factors. Regardless of the stroke, these factors may be responsible for development of AF.

Obesity Paradox and 12 Month Outcome in Patients with Atrial Fibrillation

BACKGROUND AND AIM

Obesity increases the risk of atrial fibrillation (AF) while it may impact the outcome of patients with AF. The clinical implications of this relationship are not completely clear. We aimed to analyze the association of traditional anthropometric measures of excessive adiposity with 12 month case fatality rate (CFR) in patients with AF.

METHODS

This was a multicenter, longitudinal, observational study on adults with documented AF, excluding records of AF secondary to reversible causes. Anthropometric variables were registered at baseline, and a central committee validated the 12 month outcomes.

RESULTS

We studied 1193 patients (median age: 69.14 years, 55.2% women). At baseline, rhythm control was established for 476 (39.9%) subjects, while frequency control was offered to 717 (60.1%) participants. The 12 month all-cause CFR was 8.9%. A high basal body mass index (BMI), waist-to-height ratio (WHtR) and waist circumference (WC) were associated with lower CFR in bivariate analyses. In a Cox-proportional hazards model, variables associated with 12 month all-cause CFR were BMI categories (HR: 0.736, 95% CI: 0.584-0.928), chronic heart failure (HR: 1.738, 95% CI: 1.127-2.680), chronic kidney disease (HR: 2.269, 95% CI: 1.162-4.429) and carotid stenosis >50% (HR: 5.342, 95% CI: 1.661-17.181).

CONCLUSION

The risk of death at one year in patients with AF is inversely associated with a high BMI and directly associated with the presence of chronic kidney disease, carotid stenosis, and chronic heart failure in this cohort of patients with AF. The causes and implications of this apparent obesity paradox should be addressed in the future.

LDL-C/HDL-C is associated with ischaemic stroke in patients with non-valvular atrial fibrillation: a case-control study

BACKGROUND

This study explored the relationships between the low-/high-density lipoprotein cholesterol ratio (LDL-C/HDL-C) and other clinical indicators and ischaemic stroke (IS) in patients with non-valvular atrial fibrillation (NVAF) in Xinjiang. The findings could provide a theoretical and therapeutic basis for NVAF patients.

METHODS

NVAF patients who were admitted to 10 medical centres across Xinjiang were divided into stroke (798 patients) and control (2671 patients) groups according to the occurrence of first acute IS. Univariate and multivariate logistic regression analysis were used to examine the independent risk factors for IS in NVAF patients. Factor analysis and principal component regression analysis were used to analyse the main factors influencing IS. Receiver operating characteristic (ROC) curve analysis was used to evaluate the discriminatory ability of LDL-C/HDL-C for predicting the occurrence of IS.

RESULTS

The stroke group had an average age of 71.64 ± 9.96 years and included 305 females (38.22%). The control group had a mean age of 67.30 ± 12.01 years and included 825 females (30.89%). Multivariate logistic regression showed that the risk of IS in the highest LDL-C/HDL-C quartile (≥2.73) was 16.23-fold that of the lowest quartile (< 1.22); IS risk was 2.27-fold higher in obese patients than in normal-weight subjects; IS risk was 3.15-fold higher in smoking patients than in non-smoking patients. The area under the ROC curve of LDL-C/HDL-C was 0.76, the optimal critical value was 2.33, the sensitivity was 63.53%, and the specificity was 76.34%. Principal component regression analysis showed that LDL-C/HDL-C, age, smoking, drinking, LDL-C and hypertension were risk factors for IS in NVAF patients.

CONCLUSIONS

LDL-C/HDL-C > 1.22, smoking, BMI ≥24 kg/m² and CHA₂DS₂-VASc score were independent risk factors for IS in NVAF patients; LDL-C/HDL-C was the main risk factor.

Discriminating factors excluding patients from a catheter-based left atrial appendage closure and an outcome analysis of non-intervened and intervened patients

Introduction

The catheter-based left atrial appendage closure (LAAC) has evolved as an alternative to oral anticoagulation (OAC) among non-valvular atrial fibrillation (AF) patients in whom long-term OAC is contraindicated. In daily practice, however, a sizeable number of patients who have been referred for an LAAC do not receive this intervention. This study aimed primarily to investigate the factors deterring the practice of an LAAC in referred AF patients, and secondarily to compare the complication rates of intervened patients with those who had refused the intervention within 1 year.

Material and methods

This retrospective single-centre study includes 200 patients. After a thoroughly conducted clinical selection process, 161 of these patients (80.5%) were excluded from receiving an LAAC intervention.

Results

An analysis comparing these patients to those receiving an LAAC reveales that a higher proportion of intervened patients had suffered a prior gastrointestinal bleeding (48.7 vs. 28.0%; p = 0.013) as well as a haemorrhagic stroke (12.8 vs. 2.5%; p = 0.015), and was not anticoagulated at the time of presentation (35.9 vs. 14.9%; p = 0.006). The main reason for not conducting the procedure was patient refusal (62.1%) followed by multimorbidity (16.8%). The annual rate of ischaemic strokes and bleedings among patients refusing the intervention was 2.1% and 29.5%, respectively, and this was not statistically different from the intervened patients (each p > 0.05).

Conclusions

The reasons why patients did not undergo the catheter-based LAAC were mainly reluctance for the procedure and multimorbidity. Furthermore, it could be assumed that the potential benefit of the LAAC may not be realised within the first year.

Cerebrovascular accidents differ between patients with atrial flutter and patients with atrial fibrillation

INTRODUCTION

Few studies have explored the potential impact of atrial flutter (AFl) on ischaemic stroke (IS) outcome. The aim of the present study was to compare the clinical course of IS in patients with AFl and patients with atrial fibrillation (AF).

MATERIAL AND METHODS

A retrospective analysis of patients consecutively admitted to a tertiary care centre between 2013 and 2015 due to IS or transient ischaemic attack with permanent AFl or permanent or persistent AF was performed.

RESULTS

The study groups consisted of 528 patients, including 490 (92.8%) patients with AF and 38 (7.2%) patients with AFl. The mean age and prestroke CHA2DS2-VASc scores were similar between the patients with AFl and those with AF. Most IS cases in the AF group were classified as cardioembolic strokes (74.9% vs. 39.5% in AFl, p < 0.01), and lacunar strokes were the most common in the AFl group (47.4% vs. 14.3% in AF, p < 0.01). The multivariable analysis revealed that the presence of AF (OR = 8.6, 95% CI: 1.2-57, p = 0.02), lacunar stroke (OR = 0.1, 95% CI: 0.03-0.31, p < 0.001), baseline Rankin scale score (OR = 16.6, 95% CI: 9.8-28), lack of prestroke therapeutic anticoagulation (OR = 6.1, 95% CI: 1.1-33), diabetes (OR = 2.9, 95% CI: 1.3-6.5, p < 0.01), chronic heart failure (OR = 14.2, 95% CI: 5.8-34, p < 0.001), and current smoking (OR = 0.92, 95% CI: 0.39-0.99, p < 0.01) were significantly associated with the stroke outcome.

CONCLUSIONS

Disabling or fatal IS was observed less often in patients with AFl than in patients with AF. This finding can possibly be explained by the more frequent occurrence of lacunar strokes in the AFl group compared with that in the AF group.