vitamin-k-semiquinone-radical and Cognitive-Dysfunction

The prevalence of atrial fibrillation (AF) is increasing as the population ages. AF treatment-related complications also increase markedly in older adults (defined as ≥75 years of age for this review). The older AF population has a high risk of stroke, bleeding, and death. Syncope and fall-related injuries are the most common reasons for nonprescription of oral anticoagulation (OAC), and are more common in older adults when OACs are used with antiarrhythmic drugs. Digoxin may be useful for rate control, but associations with increased mortality limit its use. Beyond rate and rhythm control considerations, stroke prophylaxis is critical to AF management, and the benefits of direct OACs, compared with warfarin, extend to older adults. Invasive procedures such as AF catheter ablation, pacemaker implantation/atrioventricular junction ablation, and left atrial appendage occlusion may be useful in appropriately selected cases. However, older adults have generally been under-represented in clinical trials.

Topics: Accidental Falls; Aged; Alcohol Drinking; Anti-Arrhythmia Agents; Anticoagulants; Atrial Appendage; Atrial Fibrillation; Catheter Ablation; Cognitive Dysfunction; Coronary Artery Disease; Cost-Benefit Analysis; Decision Making, Shared; Dementia; Diabetes Mellitus; Dual Anti-Platelet Therapy; Exercise; Frailty; Heart Failure; Humans; Hypertension; Overweight; Polypharmacy; Primary Prevention; Risk Assessment; Secondary Prevention; Sleep Apnea, Obstructive; Stroke; Vitamin K; Weight Loss

Atrial fibrillation (AF) is a common cardiac rhythm disturbance and is associated with a 5-fold increased risk of stroke. The most important risk factors for stroke in patients with AF are previous stroke and age ≥ 75 years. Canadian guidelines recommend anticoagulant therapy for patients with AF who are older than the age of 65 years, but the elderly often remain undertreated, primarily because of concerns regarding bleeding. Non-vitamin K oral anticoagulants appear to be safer, at least as efficacious, and more convenient than warfarin, and are a cost-effective alternative for elderly patients with AF. We review the evidence for the use of antithrombotic agents for stroke prevention in elderly patients (age ≥ 75 years) with nonvalvular AF.

Topics: Accidental Falls; Aged; Anticoagulants; Atrial Fibrillation; Cognitive Dysfunction; Coronary Artery Disease; Fibrinolytic Agents; Hemorrhage; Humans; Platelet Aggregation Inhibitors; Polypharmacy; Renal Insufficiency; Risk Assessment; Stroke; Vitamin K

The association between use of non-vitamin K antagonist oral anticoagulants (NOACs) with cognitive impairment in atrial fibrillation (AF) remains unknown.. An electronic search of Medline, Embase, Cochrane Library databases and ClinicalTrials.gov Website will be performed for randomized controlled trials (RCTs) that reported cognitive impairment events and observational nationwide database studies that reported adjusted hazard ratio (HR) in AF patients with NOACs. The primacy outcome will be a composite of any forms of cognitive impairment. HRs and their 95% confidence intervals (95% CI) will be calculated by using fixed- and random-effects models. Subgroup analyses will be undertaken based on individual NOACs, study types and follow-up duration.. This study will provide evidence of the association between use of NOACs and risk of cognitive impairment in patients with AF by pooling the results of RCTs and real-world studies.. The results will bring about vigorous evidence in this topic and provide optimal anticoagulation strategy in AF patients at high risk of cognitive disorder.. Ethical approval is not applicable for this study.. CRD42018103849.

Topics: Aged; Anticoagulants; Atrial Fibrillation; Blood Coagulation; Cognitive Dysfunction; Female; Humans; Male; Middle Aged; Randomized Controlled Trials as Topic; Risk Factors; Systematic Reviews as Topic; Vitamin K

INTRODUCTION    Most patients with atrial fibrillation (AF) are elderly and may have an increased risk of cognitive disorders. Low mean values of the therapeutic international normalized ratio (INR) range (TTR) (≤60%) are associated with increased risk of stroke, vascular events, and bleeding complications. OBJECTIVES    The aim of the study was to evaluate the efficacy of long-term anticoagulant therapy in patients treated with vitamin K antagonists (VKAs), depending on their cognitive functions. In addition, we used the SAMe-TT2R2 risk score to predict the risk of ineffective anticoagulation. PATIENTS AND METHODS The analysis comprised 154 patients (68 men and 86 women; mean age, 76 ±10 years) with AF and indications for long-term therapy with VKA (CHA2DS2-VASc score ≥1, HAS-BLED score <3). Cognitive functions were evaluated using the Mini-Mental State Examination (MMSE) score. The efficacy of VKA therapy was determined by the TTR values from the preceding 6 months of treatment. We used the SAMe-TT2R2 score to identify patients who were likely to have poor INR control. RESULTS    Depending on the number of MMSE points, patients treated with VKAs were divided into 2 groups: patients with normal cognitive functions (MMSE score ≥27; n = 62) and those with cognitive impairment (MMSE score <27; n = 42). Despite the fact that all patients had indications for anticoagulant therapy, 50 patients (32%) received no VKAs on admission. The mean TTR value exceeded 60% in 61% of patients with an MMSE score of 27 points or higher, whereas mean TTR value was 28% in patients with an MMSE score of less than 27 (P <0.0001). Patients with a SAMe-TT2R2 score of 0 to 1 had higher TTR values than those with a SAMe-TT2R2 score of 2 or higher (r = -0.24; P <0.05 ). The cognitive status was significantly more impaired in patients with persistent and permanent AF compared with patients with paroxysmal AF (MMSE score, 25.8 ±3.7 vs 28.6 ±2; P <0.0001). CONCLUSIONS    Cognitive disorders in patients with AF significantly reduce the efficacy of VKA therapy. The decision to administer VKA treatment should be based not only on the CHA2DS2-VASc and HAS-BLED scores, but also on the SAMe-TT2R2 score and the evaluation of the patient's cognitive functions.

Topics: Aged; Aged, 80 and over; Anticoagulants; Atrial Fibrillation; Blood Coagulation; Cognitive Dysfunction; Female; Humans; International Normalized Ratio; Male; Middle Aged; Predictive Value of Tests; Stroke; Treatment Outcome; Vitamin K