Functional MRI-Specific Alterations in Executive Control Network in Mild Cognitive Impairment: An ALE Meta-Analysis

Background: Mild cognitive impairment (MCI) is considered to be a transitional state between normal aging and Alzheimer's dementia (AD). Recent studies have indicated that executive function (EF) declines during MCI. However, only a limited number of studies have investigated the neural basis of EF deficits in MCI. Herein, we investigate the changes of regional brain spontaneous activity and functional connectivity (FC) of the executive control network (ECN) between high EF and low EF groups.Methods: According to EF composite score (ADNI-EF) from the Alzheimer's Disease Neuroimaging Initiative (ADNI), we divided MCI into two groups, including the MCI-highEF group and MCI-lowEF group. Resting-state functional MRI was utilized to investigate the fractional amplitude of low-frequency fluctuation (fALFF) and ECN functional connectivity across 23 healthy controls (HC), 11 MCI-highEF, and 14 MCI-lowEF participants. Moreover, a partial correlation analysis was carried out to examine the relationship between altered fALFF or connectivity of the ECN and the ADNI-EF.Results: Compared to HC, the MCI-highEF participants demonstrated increased fALFF in the left superior temporal gyrus (STG), as well as decreased fALFF in the right precentral gyrus, right postcentral gyrus, and left middle frontal gyrus (MFG). The MCI-lowEF participants demonstrated increased fALFF in the cerebellar vermis and decreased fALFF in the left MFG. Additionally, compared to HC, the MCI-highEF participants indicated no significant difference in connectivity of the ECN. Furthermore, the MCI-lowEF participants showed increased ECN FC in the left cuneus and left MFG, as well as decreased ECN functional connectivity in the right parahippocampal gyrus (PHG). Notably, the altered fALFF in the left MFG was positively correlated to ADNI-EF, while the altered fALFF in cerebellar vermis is negatively correlated with ADNI-EF across the two MCI groups and the HC group. Altered ECN functional connectivity in the right PHG is negatively correlated to ADNI-EF, while altered ECN functional connectivity in the left cuneus is negatively correlated to ADNI-EF across the three groups.Conclusions: Our current study demonstrates the presence of different patterns of regional brain spontaneous activity and ECN FC in the MCI-highEF group and MCI-lowEF group. Furthermore, the ECN FC of the MCI-highEF group was not disrupted, which may contribute to retained EF in MCI.

Download Full-text

White Matter Hyperintensity Load Drives Differential Grey Matter Changes in Mild Cognitive Impairment

10.21203/rs.3.rs-131979/v1 ◽

2020 ◽

Author(s):

Ashwati Vipin ◽

Benjamin Yi Xin Wong ◽

Dilip Kumar ◽

Audrey Low ◽

Kok Pin Ng ◽

...

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

White Matter ◽

Executive Control ◽

Grey Matter ◽

White Matter Hyperintensities ◽

White Matter Hyperintensity ◽

Grey Matter Volume ◽

Executive Control Network ◽

Matter Volume

Abstract Background: Small-vessel cerebrovascular disease often represented as white matter hyperintensities on magnetic resonance imaging, is considered an important risk factor for progression to dementia. Grey matter volume alterations in Alzheimer’s disease-specific regions comprising the default mode network and executive control network are also key features of early Alzheimer’s disease. However, the relationship between increasing white matter hyperintensity load and grey matter volume needs further examination in the cognitively normal and mild cognitive impairment. Here, we examined the load-dependent influence of white matter hyperintensities on grey matter volume and cognition in the cognitively normal and mild cognitive impairment stages.Methods: Magnetic resonance imaging data from 93 mild cognitive impairment and 90 cognitively normal subjects were studied and white matter hyperintensity load was categorized into low, medium and high terciles. We examined how differing loads of white matter hyperintensities related to whole-brain voxel-wise and regional grey matter volume in the default mode network and executive control network. We further investigated how regional grey matter volume moderated the relationship between white matter hyperintensities and cognition at differing white matter hyperintensity loads.Results: We found differential load-dependent effects of white matter hyperintensity burden on voxel-wise and regional grey matter atrophy in only mild cognitive impairment subjects. At low load, white matter hyperintensity load was positively related to grey matter volume in the executive control network but at high load, white matter hyperintensity load was negatively related to grey matter volume across both the executive control and default mode networks and no relationship was observed at medium white matter hyperintensity load. Additionally, negative associations between white matter hyperintensities and domains of memory and executive function were moderated by regional grey matter volume. Conclusions: Our results demonstrate dynamic relationships between white matter hyperintensity load, grey matter volume and cognition in the mild cognitive impairment stage. Interventions to slow the progression of white matter hyperintensities, instituted when white matter hyperintensity load is low could potentially prevent further cognitive decline.

Download Full-text

Supplemental Material for Risk of Progression to Alzheimer’s Disease for Different Neuropsychological Mild Cognitive Impairment Subtypes: A Hierarchical Meta-Analysis of Longitudinal Studies

Psychology and Aging ◽

10.1037/pag0000294.supp ◽

2018 ◽

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Longitudinal Studies ◽

Meta Analysis ◽

Risk Of Progression

Download Full-text

Prevalence of mild cognitive impairment in patients with hypertension: a systematic review and meta-analysis

Hypertension Research ◽

10.1038/s41440-021-00704-3 ◽

2021 ◽

Author(s):

Jiawei Qin ◽

Zexiang He ◽

Lijian Wu ◽

Wanting Wang ◽

Qiuxiang Lin ◽

...

Keyword(s):

Systematic Review ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Meta Analysis

Download Full-text

The Prevalence of Mild Cognitive Impairment among Chinese People: A Meta-Analysis

Neuroepidemiology ◽

10.1159/000512597 ◽

2021 ◽

Vol 55 (2) ◽

pp. 79-91

Author(s):

Yan Deng ◽

Siqi Zhao ◽

Guangwen Cheng ◽

Jiajia Yang ◽

Benchao Li ◽

...

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Diagnostic Criteria ◽

Meta Analysis ◽

Random Effect ◽

Random Effect Model ◽

Internal Validity ◽

Screening Tools ◽

Chinese Elderly ◽

Pooled Prevalence

Background: Mild cognitive impairment (MCI) induced the majority number of dementia patients. The prevalence of MCI in China varied across studies with different screening tools and diagnostic criteria. Objective: A systematic review and meta-analysis was conducted to estimate the pooled MCI prevalence among the population aged 55 years and older in China. Methods: PubMed, EMBASE, CNKI, Wanfang, CQVIP, and CBMdisc were searched for studies on prevalence of MCI among Chinese elderly between January 1, 1980, and February 10, 2020. The quality assessment was conducted via external validity, internal validity, and informativity, the pooled prevalence was calculated through the random-effect model, and the homogeneity was evaluated by Cochran’s Q test and I2. Results: Fifty-three studies with 123,766 subjects were included. The pooled prevalence of MCI among Chinese elderly was 15.4% (95% CI: 13.5–17.4%). Subgroup analyses indicated that the prevalence calculated with different screening tools was 20.2% (95% CI: 15.1–25.9%) for Montreal Cognitive Assessment (MoCA) and 13.0% (95% CI: 10.7–15.5%) for Mini-Mental State Examination (MMSE). According to different diagnostic criteria, the prevalence was 14.8% (95% CI: 12.2–17.6%) for Petersen criteria, 15.0% (95% CI: 12.7–17.5%) for DSM-IV, and 21.2% (95% CI: 17.5–25.2%) for Chinese Expert Consensus on Cognitive Impairment (CECCI). Besides, women, older adults, illiterate people, rural residents, and those who lived with unhealthy lifestyles and morbidity showed higher prevalence. Conclusions: The prevalence of MCI in China was 15.4%, which varied by demographics, lifestyles, morbidity, screening tools, and diagnostic criteria. In further studies, screening tools and diagnosis criteria should be considered when estimating MCI prevalence.

Download Full-text