The Occurrence and Longitudinal Changes of Cognitive Impairment After Acute Ischemic Stroke

More and more evidence suggests that cognitive impairment (CI) after stroke is closely related to the quality of life of stroke patients. The primary aim of this study is to investigate the occurrence and longitudinal changes of CI at different stages after acute ischemic stroke (AIS) in Chinese patients.

The data of this study come from the impairment of cognition and Sleep after acute ischemic stroke or transient ischemic attack in Chinese patients study (ICONS), a nationwide multicenter prospective registry that recruited consecutive AIS or transient ischemic attack in-hospital patients within 7 days after onset. Patients were followed for Montreal Cognitive Assessment (MoCA) scale at 2-week (2w), 3 months (3m) and 12 months (12m). CI was defined as MoCA score≦22. No cognitive impairment (NCI) was defined as MoCA score>22.

A total of 2432 AIS patients were enrolled in this study. Overall, 72.94% of patients were male and the average age was 60.95 years. Median National Institutes of Health Stroke Scale score was 3. The occurrence rate of CI was 52.38%, 35.55% and 34.16% at 2w, 3m and 12m. Among patients with CI at 2w and 3m, 39.9% and 27.9% of patients returned to NCI at next follow-up point. At 3m and 12m follow-up, there were also 9.6% and 12.7% new CI patients. The two cognitive items with the highest abnormal rate were "Delayed recall" (89.35%, 83.33% and 82.80%) and "Visuospatial/executive" (78.91%, 73.42% and 70.08%). The cognitive item with the highest percentage of improved patients was "Orientation" (60.91-76.68%), and the cognitive item with the lowest percentage of improved patients was "Language" (35.85-44.50%).

CI had a relatively high occurrence at 2w to 12m after AIS. CI at 3m and 12m was significantly lower than that at 2w after stroke. The occurrence of abnormalities and recovery probability for different cognitive items also differed greatly.