Objective: Few data are available on the prevalence of cognitive impairment no dementia (CIND) in rural China. The aim of this study was to estimate the prevalence of CIND in individuals aged 60 years and older in a large rural community, and to analyze the associated risk factors. Methods: A two-phase, door-to-door epidemiological study was used for residents aged 60 years and older in Ji County, a rural county near Tianjin in Northern China. In phase 1 of the study, the Mini-Mental State Examination and Clinical Dementia Rating were administered for screening purposes. In phase 2, the subjects who screened positive were further examined by neurologists. A total of 5,744 individuals underwent the home visit interview, where demographic variables and comorbidities were recorded; 5,550 individuals completed the two phases. CIND was diagnosed by the Aging, Demographics and Memory Study on CIND criteria. The odds ratio (OR) for each risk factor was calculated by logistic regression analysis. Results: The prevalence of CIND among those aged 60 years and older was 23.3%. The prevalence of CIND was lower among those with a higher level of education or social involvement. CIND was more prevalent in females, older individuals, those with a past history of stroke, and those living without a partner. Significant risk factors were found by multivariate analyses: past history of stroke (OR = 1.889; 95% CI: 1.437-2.483); being female (OR = 1.546; 95% CI: 1.305-1.832); and having no partner (divorced, widowed or single; OR = 1.250; 95% CI: 1.042-1.499). In turn, level of education (OR = 0.560; 95% CI: 0.460-0.681) and engagement in social activities (OR = 0.339; 95% CI: 0.258-0.404) were protective factors. Conclusions: This is the first large-scale community-based epidemiological study assessing the prevalence of cognitive loss in the rural Chinese population. The total prevalence of CIND observed was 23.3%, which was higher than in other studies in Western and Asian countries. Living without a partner, female gender and previous stroke increased the risk of CIND, whereas a higher level of education and engagement in social activities reduced the risk of CIND.

Introduction: Currently, there is still clinical overlap between dementia with Lewy bodies (DLB) and Alzheimer's disease (AD) patients, which may affect the accuracy of the early diagnosis of DLB. For better diagnosis and prognosis, further exploration of local cortical atrophy patterns and white matter lesions is needed.Methods: We reviewed the outpatient medical records of 97 DLB patients and 173 AD patients from January 2018 to September 2020 along with 30 matched outpatient clinic normal elderly people. MRI visual rating scales, including medial temporal lobe atrophy (MTA), global cortical atrophy-frontal subscale (GCA-F), posterior atrophy (PA), Fazekas scale, Evans Index and cerebral microbleeds were evaluated and analyzed in DLB and AD patients with different severities and normal controls.Results: Overall, patients with DLB had higher scores on all visual rating scales than the normal controls. Meanwhile, compared with AD, DLB had lower MTA scores in the mild to moderate groups (both p ≤ 0.001), but the GCA-F and PA scores were similar (all p > 0.05). The Fazekas scores in the moderate to severe DLB group were lower than those in the AD group (p = 0.024 and p = 0.027, respectively). In addition, the diagnostic performance and sensitivity of multiple imaging indicators for DLB were better than that of MTA alone (the combination of MTA, GCA-F, PA, Fazekas visual rating scales, AUC = 0.756, 95%CI: 0.700–0.813, sensitivity = 0.647, specificity = 0.804 and MTA visual rating scale, AUC = 0.726, 95%CI: 0.667–0.785, sensitivity = 0.497, specificity = 0.876, respectively).Conclusion: The medial temporal lobe of DLB patients was relatively preserved, the frontal and parietal lobes were similarly atrophied to AD patients, and the white matter hyperintensity was lighter than that in AD patients. Combined multiple visual rating scales may provide a novel idea for the diagnosis of early DLB.

Background: Research on sex ratios of Lewy body dementia is controversial, established in small samples, and rarely focused on prodromal stage. The objective is to investigate the clinical sex ratios (men/women) and their associations with clinical features among individuals with mild cognitive impairment with Lewy bodies (MCI-LB), dementia with Lewy bodies (DLB), Parkinson’s disease with mild cognitive impairment (PD-MCI), and Parkinson’s disease with dementia (PDD) in China. Methods: We conducted a multicenter cohort study, including 1038 individuals with probable MCI-LB, DLB, PD-MCI, or PDD diagnosis from 22 memory clinics in China from January 2018 to March 2022, and recorded their demographic and clinical data by reviewing medical records. Descriptive and regression analyses were used to calculate the sex ratio (men/women), and its associations with demographic and clinical data. Results: In this study, men comprised 35.14% (men/women sex ratio = 0.54) for MCI-LB, 46.72% (men/women sex ratio = 0.88) for DLB, 63.56% (men/women sex ratio = 1.74) for PD-MCI, and 52.40% (men/women sex ratio = 1.10) for PDD. Sex ratios roughly increased with age. Men had more parkinsonism (p = 0.000) and less fluctuating cognition (p = 0.024) in MCI-LB, and those with PD-MCI had more RBD (p = 0.001). Women with PD-MCI had lower MMSE scores (β ± standard error = − 1.24 ± 0.58, p = 0.04), more irritability (0.95 ± 0.46, p = 0.04) and fluctuating cognition (− 3.41 ± 1.31, p = 0.01), and less parkinsonism (− 2.10 ± 0.97, p = 0.03) than men after adjusting for demographic and cardiometabolic conditions. Conclusion: There were more women in DLB and MCI-LB, and more men in PD-MCI and PDD. The sex distribution, demographic, and clinical characteristics differed, which strengthened the independence and heterogeneity of the four diseases, and indicated sex-sensitive strategies for management of dementia necessary.

Aims: To estimate the proportions of specific hypometabolic patterns and their association with neuropsychiatric symptoms (NPS) in patients with cognitive impairment (CI).Methods: This multicenter study with 1037 consecutive patients was conducted from December 2012 to December 2019. ¹⁸F‐FDG PET and clinical/demographic information, NPS assessments were recorded and analyzed to explore the associations between hypometabolic patterns and clinical features by correlation analysis and multivariable logistic regression models.Results: Patients with clinical Alzheimer's disease (AD, 81.6%, 605/741) and dementia with Lewy bodies (67.9%, 19/28) mostly had AD‐pattern hypometabolism, and 76/137 (55.5%) of patients with frontotemporal lobar degeneration showed frontal and anterior temporal pattern (FT‐P) hypometabolism. Besides corticobasal degeneration, patients with behavioral variant frontotemporal dementia (36/58), semantic dementia (7/10), progressive non‐fluent aphasia (6/9), frontotemporal lobar degeneration and amyotrophic lateral sclerosis (3/5), and progressive supranuclear palsy (21/37) also mostly showed FT‐P hypometabolism. The proportion of FT‐P hypometabolism was associated with the presence of hallucinations (R = 0.171, p = 0.04), anxiety (R = 0.182, p = 0.03), and appetite and eating abnormalities (R = 0.200, p = 0.01) in AD.Conclusion: Specific hypometabolic patterns in FDG‐PET are associated with NPS and beneficial for the early identification and management of NPS in patients with CI.

Emerging evidence indicates that globus pallidus (GP) function can be modulated by orexin-A in movement disorders, while its role in Alzheimer’s disease (AD) and dementia with Lewy bodies (DLB) remains unclear. We have ever found the increased blood-brain barrier (BBB) permeability in GP and plasma orexin-A level were respectively correlated with plasma amyloid-β (Aβ) levels in AD and DLB. However, the interplay among these factors and their underlying mechanisms is poorly understood. In this study, we measured plasma orexin-A, Aβ1–40, and Aβ1–42 levels, along with BBB permeability in GP via dynamic contrast-enhanced MRI, in 20 healthy controls (HC), 25 patients with AD, and 16 patients with DLB from December 2020 to April 2022. Demographic, clinical, and neuropsychological data were collected. The mediation analysis models were used to calculate the mediating effect of Aβ on the associations between orexin-A and BBB permeability in GP (reflected by Ktrans or Vp values). Patients with AD had significantly higher plasma orexin-A than DLB (p = 0.047) and HC (p < 0.001), while DLB showed elevated Aβ1–40 and Aβ1–42 versus AD and HC (all p < 0.05). HC had higher Vp values of right GP than AD (p = 0.037). Patients with AD displayed higher Ktrans for left GP and average left-right Ktrans than both HC and DLB (all p < 0.05). Ktrans and Vp values for GP correlated with MoCA, CDR, HAMD, and NPI scores in patients with AD and DLB, and with plasma orexin-A, Aβ1–40, and Aβ1–42 in HC. After adjusting for confounders, Aβ1–40 (Beta = -0.864, p = 0.021) and Aβ1–42 (Beta = -0.875, p = 0.039) partially mediated the link between orexin-A and Ktrans for left GP in HC. Aβ1–40 (Beta = -1.845, p = 0.042) partially mediated the link between orexin-A and Ktrans for right GP in DLB. No significant mediation was found in AD or across all participants. This study elucidates the clinical role of BBB permeability in GP in AD and DLB, highlights the partial mediating effect of Aβ on the association between orexin-A and BBB leakage. These findings provide mechanistic insights into BBB dysfunction during aging and neurodegeneration.