Cognitive function in patients with non valvular atrial fibrillation: correlation to markers of thrombogenesis

ABSTRACT

There is increasing evidence that non valvular atrial fibrillation NVAF is associated with an increased risk of asymptomatic or silent cerebral infarctions. An important question is whether these infarction are truly asymptomatic and whether anti-thrombotic treatment could be beneficial in those patients. In this study we examined components of cognitive function [Event Related Potentials "ERP[s]" P300 and Wechsler Adult Intelligence Scale "WAIS"] and markers of thrombogenesis [fibrinogen, fibrinopeptide A "FPA". platelet aggregation, platelet factor 4 "PF-4" and beta-thromboglobulin "beta T.G"] in 20 neurologically asymptomatic NVAF patients comparing them to a well matched group in sinus rhythm. In addition, parameters of cognitive function components were correlated to those of thrombogenesis in the group of AF patients. NVAF patients had significantly prolonged latency and significantly reduced amplitude of P300 component of ERPs in AF Vs sinus rhythm group respectively and significantly reduced verbal intelligence quotient [VIQ] component of [WAIS] Vs sinus rhythm group P< 0.006. In addition, NVAF patients had significantly elevated levels of fibrinogen [p< 0.01], FPA [p<0.001], significant platelet aggregation is response to 2 ug/ml collagen [p< 0.001] and 1 ug/ml collagen [P< 0.001] and significantly elevated levels of PF-4 [P< 0.01] and beta T. G [P< 0.001] compared to the group in sinus rhythm respectively. In the NVAF group, there was positive association between P300 latency of ERPs components and each of FPA and PF-4 with high P< 0.1 and marginal P= 0.05 significance respectively and significant inverse correlation between all parameters of WAIS components and those of thrombogenesis except for the relation of performance intelligence quotient [PIQ] to each of FPA and beta T.G levels. These results may aid in identifying those patients at high risk of developing dementia and may help decision making when anti thrombotic therapy is being considered in NVAF patients. We recommend cognitive