[Frequency of use of oral vitamin K antagonists in patients with atrial fibrillation and cognitive function disturbances]. / Czestosc stosowania doustnych antagonistów witaminy K u pacjentów z migotaniem przedsionków i zaburzeniami funkcji poznawczych.

UNLABELLED: The incidence of atrial fibrillation (AF) and of thromboembolic complications increases along with age. This is also the case for cognitive function disturbances; therefore their occurrence in patients (pts) with AF may hamper control of anticoagulant therapy and maintenance of therapeutic INR values. The aim of the study was to evaluate the effect of cognitive function disturbances on implementation and monitoring of the treatment with oral vitamin K antagonists (VKA) in patients with AF. The relationship between the level of cognitive function disturbances and the severity of experienced AF symptoms was defined. MATERIAL AND METHODS: The analysis included a group of 93 pts (41 males, 52 females, mean age: 76.8) with a diagnosis of AF and with indications for anticoagulation treatment with VKAs (CHA2DS2VASc > or = 2, HAS-BLED < 3), referred to the Clinic of Internal Diseases and Clinical Pharmacology of the Medical University of Lodz. In a group of pts (n = 46) treated chronically with VKAs, mean INR values at admission to the hospital were calculated and the number of results falling within the therapeutic range of 2-3, by the severity of cognitive disturbances, was analyzed. Cognitive abilities were assessed with the Mini Mental State Examination Scale (MMSE) (MMSE-Mini-mental state examination). The EHRA (European Heart Rhythm Association) classification was used to assess AF-related complaints. RESULTS: The 93 studied subjects were divided into 3 groups: group I with normal cognitive function (MMSE = 24-27) - n = 35; group II with disturbances of cognitive function without dementia (MMSE = 24-26) - n = 35 and group III with dementia (MMSE < 24) - n = 23.66% of pts with normal MMSE result were referred to the hospital because AF-related symptoms and in the group of patients with MMSE < 24 these symptoms were the cause of hospitalization in 23% of pts. Despite the fact that all patients had indications for VKAs, this treatment was not started in 40%, 51.4% and 65% of pts in group I, II and III, respectively. At admission to the hospital, therapeutic level INR values were found only in 34.8% of AF pts. 49% of pts were treated with VKAs in total. In group II, a high percentage of patients (43%) treated with aspirin was found in spite of high thromboembolic risk and no contraindications to VKAs. About 23% of pts with a normal MMSE result and 14% of pts in group II experienced AF-related symptoms preventing them from normal functioning and performing daily activities (EHRA IV). Nobody in group III reported severe AF-related symptoms. CONCLUSIONS: Along with the advancing age, there is an increase of the incidence of persistent and fixed atrial fibrillation, of the risk of thromboembolic complications and of the severity of cognitive function disturbances. Treatment with oral vitamin K antagonists was implemented much less frequently among patients with atrial fibrillation and cognitive function disturbances, as compared to the patients with normal cognitive function. The MMSE test should be routinely performed in patients with atrial fibrillation to monitor the efficacy and safety of the treatment with oral vitamin K antagonists properly. In patients with disturbances of cognitive function, significantly lower reportability of AF-related complaints was shown, as compared to individuals without these disturbances. Patients with normal MMSE result were referred to the hospital because AF-related symptoms, in the group of patients with MMSE < 23 the main reason for hospitalization was the severity of the symptoms heart failure. ECG should be a routine test performed in elderly patients with cognitive function disturbances or with dementia to detect atrial fibrillation.

Assessment of the mean time in the therapeutic INR range and the SAME-TT2R2 score in patients with atrial fibrillation and cognitive impairment.

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.