Is mini mental state examination helpful for CHA2DS2-VASc score?

Abstract

Introduction: Atrial fibrillation is an important and independent risk factor for cerebrovascular diseases and vascular dementia. There is increasing evidence that atrial fibrillation is associated with an elevated risk of asymptomatic or silent cerebral infarction and as a result may confer an increased risk of progressive cognitive impairment. Aims: To determine whether atrial fibrillation (AF) in stroke-free patients is associated with impaired cognition and structural abnormalities of the brain and to determine the correlation between thromboembolic risk and the cognitive impairment. Methods: 218 patients with non-valvular atrial fibrillation and no history of stroke, and transient ischaemic attacks were consecutively examined. All cases underwent physical examination, blood chemistry, urinalysis, chest radiography, ECG, Doppler echocardiography. To investigate the cognitive status, subjects underwent the neuro -psychological rating scale Mini Mental State Examination (MMSE). Patients with an MMSE score of <24 were considered to have severe cognitive impairment. Results: The subjects (218) (mean age 70.1±0.65 years; 59% Women) were stratified according to ECG features into 3 groups: (I) those with de novo AF (n=6; 2.8%), (II) those with paroxysmal atrial fibrillation (ie, history of >1 episode of arrhythmia lasting <48 hours) (n=40; 18.4%), and (III) those with chronic AF (ie, arrhythmia lasting >6 months) (n=172; 78.9%). Cognitive status as assessed by MMSE was found to be significantly different in the 3 groups: group I- 28.1±1.9; group II - 25.9±2.9; and group III- 24.9±2.9 (P<0.01). Thromboembolic risk (according to CHA2DS2-VASc) was similar between groups (3.1±0.6 in chronic AF vs. 2.9±0.8 in paroxysmal AF and 1.9±0.2 in de novo AF, p=0.05). There was a significant association between thromboembolic risk and the presence of cognitive disturbances (MMSE<26) (8.7% low risk, 21.4% moderate risk, and 48% high risk, p<0.05). Brain CT has shown lacunar changes or multiple cerebral ischemic areas in 52% of patients with cognitive disturbances. Among 56 patients with CHA2DS2-VASc score =1 twelve of them (21.4%) have had MMSE - 26/30, with lacunar or ischemic changes in 3/12 (25%). Conclusions: Cognitive dysfunction is common in patients with chronic atrial fibrillation. The MMSE additionally to CHA2DS2-VASc could help to identify patients with atrial fibrillation who need oral anticoagulation and those who need extra efforts to maintain effective optimal anticoagulation and improve outcomes.