Objective: To explore the characteristics of cognitive impairment of cerebral ischemia in adults to provide rationales for proper diagnosis and targeted treatment.
Methods: A battery of standardized neuropsychological tests including mini-mental state examination (MMSE) and memory and executive screening (MES) was administered in a cohort of consecutive patients with cerebral ischemia. According to the screening results, they were divided into 3 subgroups of vascular dementia (VaD), vascular mild cognitive impairment (VaMCI) and non-vascular cognitive impairment (VCI). The general profiles of 3 subgroups were compared and the characteristics of VaMCI subgroup examined. Then the relationship between the composition of cognitive impairment and the type of ischemia (stroke and transient ischemic attack) was analyzed.
Results: Fifty-six patients and 48 healthy subjects (normal control group) matched with regards to age, gender and education were recruited. Compared to normal control group, there was a decline in the scores of MMSE [(25.0 ± 5.6) vs (28.0 ± 1.4); t = 2.695, P = 0.007] and MES [(67 ± 21) vs (84 ± 7); z = 3.860, P = 0.000] in case group. There were 33 cases (58.9%) of VCI in case group, including 11 (19.6%) in VaD subgroup, 22 (39.3%) in VaMCI subgroup and 23 (41.1%) in non-VCI subgroup. And the rate of VaD/VaMCI was 1/2. The percentage of males (36.4% vs 78.3%; χ(2) = 5.720, P = 0.017) and education [(8 ± 3) vs (12 ± 4); P = 0.010] of VaD subgroup were significantly lower than that of non-VCI subgroup; the education of VaMCI subgroup was significantly lower than that of non-VCI subgroup [(7 ± 3) vs (12 ± 4); P = 0.001]; a positive correlation existed between scores of MMSE/MES and cognitive impairment. The neuropsychological tests were both sensitive and specific.In VaMCI subgroup, 22 cases (100%) presented with a deficit of at least 1 certain executive function/attention index, 21(95.5%) with at least 1 certain memory index, 17(77.3%) with at least 1 certain language index and 16(72.7%) with at least 1 certain visuospatial function index; all VaMCI cases presented with comprehensive cognitive impairment: 11 (50%) in 4 domains, 10 (45%) in 3 domains and 1 (5%) in 2 domains.No significant difference existed among 3 subgroups with regard to type of ischemia (χ(2) = 1.111, P = 0.574). In the case group, 30 patients suffered stroke and 17 (56.7%) had an onset of VCI with a rate of VaMCI/VCI at 58.8%; transient ischemic attack occurred in 26 patients and 16 (61.5%) suffered VCI with a rate of VaMCI/VCI at 75.0%.
Conclusion: Our study not only profiles the prevalence and peculiarity of cognitive impairment in patients with cerebral ischemia, but also provides concrete rationales for further diagnosis and classification of VCI.