Xiang-Fei Jia

The prevalence of dementia in urban and rural areas of China

The Chinese population has been aging rapidly and the countrys economy has experienced exponential growth during the past three decades. The goal of this study was to estimate the changes in the prevalence of dementia, Alzheimers disease (AD), and vascular dementia (VaD) among elderly Chinese individuals and to analyze differences between urban and rural areas.

Montreal Cognitive Assessment in Detecting Cognitive Impairment in Chinese Elderly Individuals: A Population-Based Study

The Montreal Cognitive Assessment (MoCA) has been proved brief and sensitive to screen for mild cognitive impairment (MCI) and early dementia in some developed countries or areas. However, little MoCA data are available from mainland China. In this study, the MoCA was applied to 8411 Chinese community dwellers aged 65 or older (6283 = cognitively normal [CN], 1687 = MCI, and 441 = dementia). The MoCA norms were established considering significant influential factors. The optimal cutoff points were 13/14 for illiterate individuals, 19/20 for individuals with 1 to 6 years of education, and 24/25 for individuals with 7 or more years of education. With the optimal cutoffs, the sensitivity of the MoCA was 83.8% for all cognitive impairments, 80.5% for MCI and 96.9% for dementia, and the specificity for identifying CN was 82.5%. These indicate that with optimal cutoffs, the MoCA is valid to screen for cognitive impairment in elderly Chinese living in communities.

The prevalence of mild cognitive impairment and its etiological subtypes in elderly Chinese

Epidemiologic studies on mild cognitive impairment (MCI) are limited in China.

The Informant Questionnaire on Cognitive Decline in the Elderly Individuals in Screening Mild Cognitive Impairment With or Without Functional Impairment

The Informant Questionnaire on Cognitive Decline in the Elderly individuals (IQCODE) is a reliable, validated informant-based instrument. Most of the studies well support the validity of the IQCODE in dementia screening, but the sensitivity of the rating scale at the early stage during the course of dementia is limited. In this study, we investigate the utility of the IQCODE for patients with mild cognitive impairment (MCI) and the discriminative power of the IQCODE in patients having MCI with and without functional impairment. The samples included mild Alzheimer disease (AD, N = 280), MCI ([N = 657], further divided into 2 subgroups: patients with MCI having functional impairment [MCI-fi, N = 357] and patients having MCI without functional impairment [MCI-fn, N = 300]), and normal cognition (NC, N = 274). The IQCODE, Mini-Mental State Examination (MMSE), and other neuropsychological tests were administered to all participants. Logistic regression and receiver–operating characteristic (ROC) curves were used to evaluate the diagnostic ability of the IQCODE, compared to the MMSE. The optimal cutoff scores of the IQCODE were 3.19 for the MCI (sensitivity/specificity: 0.979/0.714) and MCI-fn (0.900/0.817), 3.25 for the MCI-fi (0.978/0.701), and 3.31 for mild AD (0.893/0.779), while the MMSE was identical, that is 26, for both MCI and its functional normal and functional impaired subgroups (0.892/0.755, 0.867/0.745, and 0.913/0.745, respectively) and 24 for mild AD (0.807/0.836). The discriminating accuracy of the IQCODE was slightly superior to that of the MMSE but did not reach statistical significance. Our study suggests that the IQCODE might be useful in screening for MCI, with hierarchical scores indicating functional normal or impaired.

Stage-Specific Gender Differences in Cognitive and Neuropsychiatric Manifestations of Vascular Dementia

Studies on gender differences in the clinical manifestations of vascular dementia (VaD) are still lacking. In the present study, gender comparisons of cognitive and neuropsychiatric profiles were conducted separately for mild and moderate-to-severe VaD in a total of 467 patients with VaD. There were no significant gender differences in cognitive manifestations, except that females performed better on immediate verbal recall than males in mild stage. Women were more likely to exhibit delusions (15.5% vs 7.4%), hallucinations (9.5% vs 3.4%), and depression (43.1% vs 27.3%) in mild stage. The predominance of male patients was observed in apathy at moderate-to-severe stage (50.5% vs 34.8%). To conclude, gender differences existed in neuropsychiatric symptoms of VaD and were especially pronounced in mild stage. Delusions, hallucinations, and depression were more prevalent in females in mild VaD, with the male predominance only in apathy in the later stage.

Apolipoprotein E ε4 status modifies the effects of sex hormones on neuropsychiatric symptoms of Alzheimer's disease.

Background: Studies on the associations between sex hormones and multiple neuropsychiatric symptoms of Alzheimer’s disease (AD) are lacking. Apolipoprotein E (APOE) ε4 status may modify the effects of sex hormones on neuropsychiatric symptoms. Methods: A total of 86 male and 87 female AD patients participated in the present study. The adjusted associations between symptoms on the Neuropsychiatric Inventory and serum levels of estradiol (total, bioavailable) and testosterone (total, bioavailable) were analyzed. Results: Agitation/aggression was negatively associated with quartiles of bioavailable estradiol among male patients, and positively associated with testosterone levels among female patients. The modifying effects of APOE genotype only existed in female patients. Those females with higher levels of estradiol and the ε4 allele had higher odds of agitation/aggression. Furthermore, the testosterone × APOE ε4 status interaction was positively associated with hallucinations in female patients. Conclusion: There were sex-specific effects of sex hormones on agitation/aggression in AD. Sex hormones and APOE ε4 status synergistically influence some neuropsychiatric symptoms among female but not male AD patients.

Elevated plasma angiogenesis factors in Alzheimer's disease.

Evidence has shown that aberrant angiogenesis is an integral part of Alzheimers disease (AD). Angiogenesis is a complex process requiring successive activation of a rather large series of factors. The aim of this study was to determine which angiogenesis molecule(s) abnormalities were changed in plasma of AD subjects and whether plasma levels of angiogenesis factors were associated with cognitive function and risk of AD. Discovery-phase antibody arrays were used to detect plasma concentrations of 55 angiogenesis-related factors. Enzyme-linked immunosorbent assays (ELISAs) in a large cohort were further performed to identify the association of plasma angiogenesis factors with AD. We found that plasma angiogenin (ANG) and tissue inhibitor of matrix metalloproteinase-4 (TIMP-4) levels were higher in patients with AD than those in normal subjects. Significantly higher ANG and TIMP-4 were observed in the severe AD group relative to the mild AD. There were different levels of plasma ANG and TIMP-4 compared with vascular dementia and other dementias. Age or gender had no major effects on levels of these proteins. Plasma ANG and TIMP-4 levels tended to be higher in ApoE ε4 carriers compared with non-carriers, but not significantly. A multiple regression analysis after adjusting for covariates revealed correlations between plasma ANG and TIMP-4 and the MMSE and CDR. Higher plasma ANG and TIMP-4 levels were associated with significant AD risk. These results demonstrate that plasma ANG and TIMP-4 may reflect the severity of cognitive function impairment, and higher levels were associated with risk of AD.

Combination of plasma biomarkers and clinical data for the detection of sporadic Alzheimer's disease

Amyloid β and alpha 1-antichymotrypsin (ACT) play an important role in the pathogenesis of sporadic Alzheimers disease (AD). The present study was to investigate whether a combination of plasma biomarkers and clinical data would discriminate AD from vascular dementia, other neurodegenerative dementia and non-demented controls. The study included 112 patients with AD, 85 patients with vascular dementia, 30 patients with other neurodegenerative dementia and 116 age-matched, non-demented controls. Although ACT, Aβ42 and the ratio of Aβ42/Aβ40 had significant differences between AD, vascular dementia, other neurodegenerative dementia and non-demented controls (P<0.001), none of them reached the sensitivity and specificity required for AD biomarkers. The combination of biomarkers and clinical data had higher discriminating power than either alone. Our results indicated that plasma biomarkers of ACT and the ratio of Aβ42/Aβ40 could discriminate AD from non-demented controls, vascular dementia, or other neurodegenerative dementias with higher diagnostic accuracy than clinical data and that if plasma biomarkers were combined with clinical data, the discriminating power was enhanced.

Diagnosis and treatment of dementia in neurology outpatient departments of general hospitals in China

The status of dementia diagnosis and treatment of neurology outpatients in general hospitals in China remains unclear.

Associations between sex hormones and cognitive and neuropsychiatric manifestations in vascular dementia (VaD)

Although numerous studies have been carried out to determine the effects of sex hormones on Alzheimers disease (AD), little is known about the associations between sex hormones and VaD. The aim of this study was to compare serum sex hormone levels between VaD patients and normal controls, and to further determine the link between sex hormones and cognitive and neuropsychiatric manifestations of VaD. Serum levels of total estradiol (TE2), total testosterone (TT), luteinizing hormone (LH), and sex hormone binding globulin (SHBG) were measured in 87 VaD patients and 110 cognitive normal controls. The levels of bioavailable estradiol (BE2) and bioavailable testosterone (BT) were calculated. The VaD patients underwent the tests of global cognitive function, verbal memory, and visuospatial, and executive ability. The Neuropsychiatric Inventory (NPI) was used to assess neuropsychiatric symptoms. Compared to controls, the testosterone and SHBG levels were lower in male VaD patients, and the estradiol levels were higher in female VaD patients. The hormones levels were not correlated with cognitive functions among either male or female VaD patients. There were no associations between hormone levels and neuropsychiatric symptoms among male patients, while the TE2 and TT levels were positively associated with apathy and anxiety, respectively among female patients. Our findings suggested there were sex hormone level changes in VaD patients in comparison with cognitive normal controls. Sex hormones were associated with neuropsychiatric symptoms among female but not male VaD patients.