Influence of Severity and Stroke Localization on the Development of Vascular Dementia and Impairment of Certain Cognitive Functions
Background: The clinical manifestations of cerebrovascular diseases (CVD) depend on the localization of the damaged region in the brain. Cognitive functions are often impaired following a stroke. Initially, CVD was referred to as atherosclerotic dementia, and was distinguished from senile dementia. Objective: The aim of this study was to examine how stroke severity and localization influence the development of vascular dementia (VD) and to identify which cognitive functions are impaired in certain types of VD. Methods: This prospective study included patients with acute stroke who were hospitalized at the Department of Neurology Tuzla, Bosnia and Herzegovina, over a one-year period. Patients were divided into the following groups: dementia of strategic infarct (DSI), cortical dementia (CD), subcortical dementia (SCD), haemorrhagic dementia (HD) and non-demented patient (NDP). Stroke localization, side and number of lesions were analyzed. Results: A total of 274 stroke patients were analyzed, of whom 190 (69%) were diagnosed with some type of VD. The odds ratio (OR) for the occurrence of dementia per point increase in NIHSS on admission was 1.131 (95% CI; 1.056 – 1.210). CD was more common in patients with right hemisphere lesions (p<0.000), whereas SCD was more frequent in those with bihemispheric lesions (p<0.0001). All assessed cognitive functions were significantly associated with CD and SCD (p<0.000). Visual perceptual (p=0.007) and visual constructive (p=0.016) functions were significantly impaired in patients with DSI. Executive functions were significantly impaired in all demented patients (p<0.0001). Conclusion: Stroke localization has a significant impact on the development of vascular dementia. All analyzed cognitive functions are significantly impaired in cortical and subcortical dementia. Visual perceptual and visual constructive functions are particularly impaired in patients with dementia of strategic infarct.