The Study Of The Characteristics Of Cognitive Impairment After Acute Mild-to-Moderate Ischemic Stroke And The Role Of SAA And A β In Cognitive Impairment

Objective:This study investigated the characteristics of cognitive function changes of different infarct locations among patients after acute mild-to-moderate ischemic stroke, and examined the relationship between serum amyloid A protein (SAA), β-amyloid (Aβ) and cognitive performance to explore the role of SAA or Aβ in prediction of cognitive impairment after acute mild-to-moderate ischemic stroke, so as to provide theoretical basis for preventing and treating vascular cognitive dysfunction after stroke in clinical.Methods:1. one hundred and five cases of acute mild-to-moderate ischemic stroke within fourteen days and thirty control cases meeting the standard set were enrolled, and they were tested by Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MOCA). First of all, compare the general information and cognitive assessment between the acute stroke group and the control group. Secondly, according to the infarct locations, patients were grouped with or without such infarct locations:the right hemisphere, the left hemisphere, the frontal lobe, the parietal lobe, the temporal lobe, the occipital lobe, brainstem, cerebellum, the basal ganglia region and thalamus, and the characteristics of cognitive changes were analyzed.2. Spearman’s correlation analysis was used to show the associations between SAA, Aβ and all influencing factors, including a 2-macroglobulin (a2-MG), age, sex, education level, smoking and other cerebrovascular risk factors. Regressions analyses were performed to determine the relationships between SAA and cognitive domains (time and place orientation, immediate memory, computing power, short memory, language, graphics execution) in MMSE or cognitive domains (visual space and execution, naming, memory, attention, calculation, language, abstract and orientation), controlling for the influencing factors. The same analyses were also applied to Aβ.Results:1. There are 41 cases (43.8%) whose MMSE score were< 27 in patients with acute mild-to-moderate ischemic stroke. The MMSE and MOCA scores of the acute stroke group are both significantly lower than those of the control group (All.P<0.01), and the significantly impaired cognitive domains included orientation, short memory, language and attention (All P<0.01). Among the one hundred and five patients with acute ischemic stroke, fifty-one cases were of the right hemisphere infarction and forty cases were of the left hemisphere infarction, while the basal ganglia infarction comes to the third place with the case number of thirty-one. The mean total scores of MMSE and MOCA suggested that patients with acute mild-to-moderate ischemic stroke suffered cognitive dysfunction. Patients with infarct locations in the right hemisphere, the left hemisphere, the frontal lobe, the parietal lobe, the temporal lobe, or the basal ganglia region suffered a more obvious decline in cognitive function than patients without those infarct locations. Executive function was the most impaired domain in patients with infarction in left hemisphere (P=0.027). The cognitive functions of language, naming, attention, and time orientation were significantly impaired in patients with the frontal infarction (All P<0.05). The domains of memory, language, attention, and visual space and executive ability were damaged more apparently among patients with the parietal infarction (P<0.05). The function of attention was obviously impaired in the infarction of temporal lobe (P=0.045). Patients with infarctions in the basal ganglia region suffered an obvious decline in language function (All P<0.05).2. All patients after acute mild-to-moderate stroke have a mild cognitive impairment. Patients with less than 6 years of education had lower mean total scores of MMSE and MOCA than those of patients with 6 or more years of education. There was a positive correlation between SAA anda2-MG as the spearman’s correlation coefficient was 0.285 (P<0.01). Generalized liner regression analyses between SAA and cognitive domains in MMSE showed that SAA was associated with the orientation of time and place, even after controlling for relevant confounding factors; SAA was associated with computing power only in modle 3 (after controlling for age, sex, education and a2-MG). However, SAA was found to have no relationship with cognitive domains in MOCA. Generalized liner regression analyses between Aβ and cognitive domains in MMSE showed that A β was negatively associated with short memory after controlling for age, sex, education levels andα2-MG; after controlling for all factors Aβ was found to have no relationship with cognitive impairment. In addition, generalized liner regression analyses between Aβ and cognitive domains in MOCA showed that there were no significant relationship between Aβ and cognitive impairment.Conclusion:1. Most of the acute mild-to-moderate ischemic stroke patients suffered cognitive dysfunction and the incidence was up to 43.8%. The characteristics of cognitive changes differed as the infarct locations were different. It suggests that making an early and specific cognitive rehabilitation scheme for patients is of great importance.2. This study also found that SAA was likely to be related to cognitive deficits, especially the orientation and calculation in MMSE among the patients after acute mild-to-moderate ischemic stroke. But additional research is required to confirm the role of SAA and to elucidate the pathopysiology of such relationship.