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Type 2 diabetes mellitus is accompanied by cognitive impairment and is associated with an increased risk of dementia. Damage to brain structures such as white matter network disruption may underlie this cognitive disturbance. In the present study, 886 non-diabetic and 163 type 2 diabetic participants completed a battery of neuropsychological tests. Among them, 38 diabetic patients and 34 non-diabetic participants that matched the patients for age/sex/education received a magnetic resonance imaging-based diffusion tensor imaging. Then we calculated the topological properties of the white matter network using a graph theoretical method to investigate network efficiency differences between groups. We found that type 2 diabetic patients had inferior performances compared to the non-diabetic controls, in several cognitive domains involving executive function, spatial processing, memory, and attention. We also found that diabetic patients exhibited a disrupted topological organization of the white matter network (including the global network properties, i.e., network strength, global efficiency, local efficiency and shortest path length, and the nodal efficiency of the right rolandic operculum) in the brain. Moreover, those global network properties and the nodal efficiency of the right rolandic operculum both had positive correlations with executive function in the patient group. The results suggest that type 2 diabetes mellitus leads to an alteration in the topological organization of the cortical white matter network and this alteration may account for the observed cognitive decline. [ABSTRACT FROM AUTHOR]

The apolipoprotein E (APOE) ɛ4 allele is the strongest genetic risk factor for Alzheimer's disease (AD). This study aimed to investigate abnormality of white matter integrity and its relationship to cognitive impairments in Chinese non-demented elderly with and without the ɛ4 allele. We assessed cognitive differences using a series of neuropsychological tests and assessed white matter integrity using tract-based spatial statistics to measure mean diffusivity and fractional anisotropy. We determined that there were no statistically significant group differences in any neuropsychological measures. However, APOEɛ4 carriers without cognitive decline exhibited widespread disruption of the white matter tracts in several areas, including the cingulum, fornix, corpus callosum, and corona radiate. Furthermore, a correlation analysis in ɛ4 carriers indicated that disruption of the right fornix stria terminalis and the genu of the corpus callosum were positively associated with cognitive impairment, including memory, executive function, spatial processing, attention, and language. The present study reveals the deleterious effects of the ɛ4 allele on white matter, and this damage may potentially serve as a biomarker in preclinical investigations. Our promising results encourage further investigation using a multidimensional longitudinal approach with larger samples. [ABSTRACT FROM AUTHOR]

Objectives To estimate the prevalence of mild cognitive impairment ( MCI) in Beijing, China, and to explore the potential protective and risk factors for MCI. Design Population-based survey. Setting The Beijing Ageing Brain Rejuvenation Initiative ( BABRI). Participants Participants randomly recruited from BABRI (N = 1,211). Measurements Participants underwent a battery of neuropsychological examinations to determine cognitive function and answered a series of personal questions. The prevalence of MCI and its subtypes were computed using Petersen's criteria. Influencing factors for MCI were estimated based on participant medical history, lifestyle, diet, and leisure activities. Results One thousand twenty (aged >55, mean 63.9 ± 6.6; 36.7% male) subjects completed the neuropsychological tests. The overall prevalence of MCI was 15.7%, with single-domain amnestic, multiple-domain amnestic, and nonamnestic subtype prevalences of 6.4%, 3.7%, and 5.6%, respectively. Eight hundred sixty-four subjects were used for the case-control analysis. Hypertension, diabetes mellitus, and cerebrovascular disease were found to be associated with MCI. Healthy diet and greater involvement in physical, intellectual, and social activities were associated with a lower risk of MCI. Conclusion The prevalence of MCI was compatible with that found in previous published reports, and the information on the epidemiology of MCI, especially risk factors, may help to explore therapeutic strategies and preventive approaches to delay conversion to dementia. [ABSTRACT FROM AUTHOR]

To address the condition that community-based geriatric services for the assessment and promotion of older adults' cognitive ability systemically aimed at delaying or preventing dementia is lacking in China. A community-based model including cognitive assessment and training, geriatric health guidance and long-term support was designed based on a prospective cohort study. Participants (N = 5593) were all from an ongoing cohort study, the Beijing Aging Brain Rejuvenation Initiative (BABRI) study. We conducted receiver operating characteristic, stepwise logistic regression and branch-and-bound algorithm analyses to select the most effective tests from the BABRI neuropsychological test battery. Canonical discriminant analysis was conducted to extract the first canonical variable as a composite index of the tests. In addition, we developed comprehensive surveys and computerized cognitive trainings targeting every cognitive domain. The BABRI brain health system (BABRI-BHS) was designed to include SCREEN, ASSESS, and DIAGNOSE sessions. When distinguishing cognitively impaired older adults from cognitively healthy older adults, the canonical variable extracted from tests in the SCREEN session achieved an area under the curve (AUC) of 0.730 [95% confidence interval (95% CI) 0.671–0.789], with a sensitivity of 0.630 and a specificity of 0.780; in the ASSESS session, the AUC was 0.906 (95% CI 0.894–0.917), the sensitivity was 0.809, and the specificity was 0.854. A stepwise screening pathway is recommended when using the BABRI-BHS in communities to divide older adults into subtypes and to provide targeted interventions and long-term geriatric health guidance. The BABRI-BHS is an effective and efficient geriatric health care solution that is suitable for community-based dementia risk screening, providing stepwise cognitive assessments and helping older adults acquire tailored interventions and guidance conveniently. [ABSTRACT FROM AUTHOR]

Facing considerable challenges associated with aging and dementia, China urgently needs an evidence-based health-care system for prevention and management of dementia. The Beijing Aging Brain Rejuvenation Initiative (BABRI) is a community-based cohort study initiated in 2008 that focuses on asymptomatic stages of dementia, aims to develop community-based prevention strategies for cognitive impairment, and provides a platform for scientific research and clinical trials. Thus far, BABRI has recruited 10,255 participants (aged 50 and over, 60.3% female), 2021 of whom have been followed up at least once at a 2- or 3-year interval. This article presents aims and study design of BABRI; summarizes preliminary behavioral and neuroimaging findings on mild cognitive impairment (MCI) and results of clinical trials on MCI; and discusses issues concerning early prevention in community, MCI diagnosis methods, and applications of database of aging and dementia. BABRI is proposed to build a systematic framework on brain health in old age., (© 2021 the Alzheimer's Association.)

Exploring how risk genes cumulatively impair brain function in preclinical phase (i.e., in cognitively normal elderly) could provide critical insights into the pathophysiology of Alzheimer's disease (AD). Working memory impairment has always been a considerable cognitive deficit in AD, which is likely under complex genetic control. Though, the APOE ɛ4 allele could damage the working memory performance in normal elderly, dissociable results have been reported. This allele may exert specific effects in contexts with other genetic variants. The rs2618516 in the spondin 1 gene (SPON1) has been associated with AD risk and brain structure in the elderly. SPON1 may interact with APOE through processing the amyloid precursor protein and suppressing amyloid-β levels. Using neuropsychological tasks from 710 individuals, we found significant SPON1 × APOE genotype interactions in working memory and executive function performances. Moreover, such interaction was also found in regional brain activations based on functional magnetic resonance imaging data with the n-back working memory task performed in a sub-cohort of 64 subjects. The effects of ɛ4 allele on activation of right inferior frontal gyrus, triangular part (IFGtriang.R) were modulated by rs2618516 in a working memory task. Furthermore, lower IFGtriang.R activation was associated with better cognitive functions. Moreover, the IFGtriang.R activation could mediate the impacts of SPON1 × APOE interactions on working memory performance. These findings suggested the importance of weighing APOE effects on brain activation under the working memory task within the context of the SPON1 genotype., (© 2018 Wiley Periodicals, Inc.)

The apolipoprotein E (APOE) ɛ4 allele is the strongest genetic risk factor for Alzheimer's disease (AD). This study aimed to investigate abnormality of white matter integrity and its relationship to cognitive impairments in Chinese non-demented elderly with and without the ɛ4 allele. We assessed cognitive differences using a series of neuropsychological tests and assessed white matter integrity using tract-based spatial statistics to measure mean diffusivity and fractional anisotropy. We determined that there were no statistically significant group differences in any neuropsychological measures. However, APOEɛ4 carriers without cognitive decline exhibited widespread disruption of the white matter tracts in several areas, including the cingulum, fornix, corpus callosum, and corona radiate. Furthermore, a correlation analysis in ɛ4 carriers indicated that disruption of the right fornix stria terminalis and the genu of the corpus callosum were positively associated with cognitive impairment, including memory, executive function, spatial processing, attention, and language. The present study reveals the deleterious effects of the ɛ4 allele on white matter, and this damage may potentially serve as a biomarker in preclinical investigations. Our promising results encourage further investigation using a multidimensional longitudinal approach with larger samples.