Cytokine Response, Tract-Specific Fractional Anisotropy, and Brain Morphometry in Post-Stroke Cognitive Impairment

Abstract

Background: Post-stroke cognitive impairment is a clinically heterogeneous condition and its types have a different course and prognosis. The aim of the present study is to address the roles of inflammation, white matter pathology, and brain atrophy in different neuropsychological types of cognitive impairment in the acute period of ischemic stroke.

Methods: In 92 patients, we performed an assessment of the cognitive status and measured concentrations of cytokines (interleukin [IL]-1β, IL-6, tumor necrosis factor-alpha, IL-10) in liquor and serum, as well as a number of magnetic resonance imaging (MRI) morphometric parameters and fractional anisotropy. The control group consisted of 14 individuals without cerebrovascular disease.

Results: All patients had a higher level of IL-10 in serum than the control group. Patients with dysexecutive cognitive impairment had a higher concentration of IL-1β and IL-10 in liquor, IL-6 level in serum, and a lower fractional anisotropy of the ipsilateral thalamus than patients with normal cognition. Patients with mixed cognitive impairment were characterized by a lower fractional anisotropy of contralateral fronto-occipital fasciculus, compared with patients with dysexecutive cognitive impairment. Patients with both dysexecutive and mixed cognitive deficit had a wide area of leukoaraiosis and a reduced fractional anisotropy of the contralateral cingulum, compared with patients without cognitive impairment. Also, we found numerous correlations between cognitive status and levels of cytokines, MRI morphometric parameters, and fractional anisotropy of certain regions of the brain.

Conclusions: The concentrations of cytokines in serum and cerebrospinal fluid studied in combination with MRI morphometric parameters and fractional anisotropy appear to be informative biomarkers of clinical types of post-stroke cognitive impairment.

Keywords: Stroke; cognitive impairment; cytokines; fractional anisotropy; neuroinflammation.