Von Willebrand factor and ADAMTS13 plasma in older patients with high CHA2DS2-VASc Score with and without atrial fibrillation

Abstract

Objective: Ischemic stroke risk rises with the increasing cardiovascular risk factors in patients with and without AF. How atrial fibrillation (AF) incrementally contributes to the risk for ischemic stroke with increasing age and multiple cardiovascular risk factors is unclear. Von Willebrand factor (vWF) is a biomarker of endothelial dysfunction.

Patients and methods: We suggested that in older patients with high CHA2DS2-VASc Score, the vWF and ADAMTS13 would be comparable between patients with and without AF. Consecutive 196 old patients (≥ 60 years, 45.9% with concomitant AF) with and without non-valve atrial fibrillation were recruited from April 2014 to April 2016. Data on baseline clinical characteristics were recorded at study entry. Plasma ADAMTS13 levels and plasma vWF levels were determined. Statistical analyses were performed using SPSS19.0 statistical software package.

Results: There were significant correlations between plasma vWf levels, ADMATS13 and CHA2DS2- VASc Score in older patients with and without AF (with AF: Spearman, r = 0.215, p < 0.05; without AF: Spearman, r = 0.197, p < 0.05). Results of research indices in our older patients were as follows: vWf 180. 79 ± 28.27 IU/dL in AF and 153.5 ± 35.54 in non AF with p < 0.001, ADAMTS13 431.5 ± 160.33 IU/dL in AF and 536.7 ± 169.96 in non AF with p < 0.05. Results of research indices in our older patients (≥ 75 year) were as follows: vWf 181.4 ± 22.04 in AF and 174.1 ± 29.45 in non AF, and ADMATS-13 412.9 ± 130.76 IU/dL in AF and 451.7 ± 153.18 in non AF. There were no differences (p > 0.05). CHA2DS2-VASc Score can predict stroke risk in old patients without atrial fibrillation. At high CHA2DS2-VASc Score, the levels of vWF and ADAMTS13 have difference in old patients (60-74) with and without AF, but in such older patients, age (≥ 75 year), there were no differences. In elderly patients, atrial fibrillation has a limited effect on VWF, and the age is an important factor affecting the endothelial function.

Conclusions: For elderly patients with a high incidence rate of stroke and thrombosis, we should pay more attention to the thrombotic events, and atrial fibrillation can be used as one of the risk factors involved and improving the risk scoring system of stroke.