The prevalence of mild cognitive impairment about elderly population in China: a meta-analysis

Development and validation of a risk prediction model for mild cognitive impairment in elderly patients with type 2 diabetes mellitus

BACKGROUND

The prevalence of mild cognitive impairment (MCI) is steadily increasing among elderly people with type 2 diabetes (T2DM). This study aimed to create and validate a predictive model based on a nomogram.

METHODS

This cross-sectional study collected sociodemographic characteristics, T2DM-related factors, depression, and levels of social support from 530 older adults with T2DM. We used LASSO regression and multifactorial logistic regression to determine the predictors of the model. The performance of the nomogram was evaluated using calibration curves, receiver operating characteristics (ROC), and decision curve analysis (DCA).

RESULTS

The nomogram comprised age, smoking, physical activity, social support, depression, living alone, and glycosylated hemoglobin. The AUC for the training and validation sets were 0.914 and 0.859. The DCA showed good clinical applicability.

CONCLUSIONS

This predictive nomogram has satisfactory accuracy and discrimination. Therefore, the nomogram can be intuitively and easily used to detect MCI in elderly adults with T2DM.

Association between drinking water sources and cognitive functioning in Chinese older adults residing in rural areas

OBJECTIVES

To explore the association between drinking water sources and cognitive functioning among older adults residing in rural China.

METHODS

Data were extracted from the 2008-2018 Chinese Longitudinal Healthy Longevity Survey. Drinking water sources were categorized according to whether purification measures were employed. The Chinese version of the Mini-Mental State Examination was used for cognitive functioning assessment, and the score of <24 was considered as having cognitive dysfunction. Cox regression analyses were conducted to derive hazard ratios (HRs) and 95% confidence intervals (CIs) for the effects of various drinking water sources, changes in such sources, and its interaction with exercise on cognition dysfunction.

RESULTS

We included 2304 respondents aged 79.67 ± 10.02 years; of them, 1084 (44.49%) were men. Our adjusted model revealed that respondents consistently drinking tap water were 21% less likely to experience cognitive dysfunction compared with those drinking untreated water (HR = 0.79, 95% CI: 0.70-0.90). Respondents transitioning from natural to tap water showed were 33% less likely to experience cognitive dysfunction (HR = 0.67, 95% CI: 0.58-0.78). Moreover, the HR (95% CI) for the interaction between drinking tap water and exercising was 0.86 (0.75-1.00) when compared with that between drinking untreated water and not exercising. All results adjusted for age, occupation, exercise, and body mass index.

CONCLUSIONS

Prolonged tap water consumption and switching from untreated water to tap water were associated with a decreased risk of cognitive dysfunction in older individuals. Additionally, exercising and drinking tap water was synergistically associated with the low incidence of cognitive dysfunction. These findings demonstrate the importance of prioritizing drinking water health in rural areas, indicating that purified tap water can enhance cognitive function among older adults.

From Gut to Brain: Uncovering Potential Serum Biomarkers Connecting Inflammatory Bowel Diseases to Neurodegenerative Diseases

Inflammatory bowel diseases (IBDs) are characterized by chronic gastrointestinal inflammation due to abnormal immune responses to gut microflora. The gut-brain axis is disrupted in IBDs, leading to neurobiological imbalances and affective symptoms. Systemic inflammation in IBDs affects the brain's inflammatory response system, hormonal axis, and blood-brain barrier integrity, influencing the gut microbiota. This review aims to explore the association between dysregulations in the gut-brain axis, serum biomarkers, and the development of cognitive disorders. Studies suggest a potential association between IBDs and the development of neurodegeneration. The mechanisms include systemic inflammation, nutritional deficiency, GBA dysfunction, and the effect of genetics and comorbidities. The objective is to identify potential correlations and propose future research directions to understand the impact of altered microbiomes and intestinal barrier functions on neurodegeneration. Serum levels of vitamins, inflammatory and neuronal damage biomarkers, and neuronal growth factors have been investigated for their potential to predict the development of neurodegenerative diseases, but current results are inconclusive and require more studies.

Data-driven clustering approach to identify novel clusters of high cognitive impairment risk among Chinese community-dwelling elderly people with normal cognition: A national cohort study

Background

Cognitive impairment is a highly heterogeneous disorder that necessitates further investigation into the distinct characteristics of populations at varying risk levels of cognitive impairment. Using a large-scale registry cohort of elderly individuals, we applied a data-driven approach to identify novel clusters based on diverse sociodemographic features.

Methods

A prospective cohort of 6398 elderly people from the Chinese Longitudinal Healthy Longevity Survey, followed between 2008-14, was used to develop and validate the model. Participants were aged ≥60 years, community-dwelling, and the Chinese version of the Mini-Mental State Examination (MMSE) score ≥18 were included. Sixty-nine sociodemographic features were included in the analysis. The total population was divided into two-thirds for the derivation cohort (n = 4265) and one-third for the validation cohort (n = 2133). In the derivation cohort, an unsupervised Gaussian mixture model was applied to categorise participants into distinct clusters. A classifier was developed based on the most important 10 factors and was applied to categorise participants into their corresponding clusters in a validation cohort. The difference in the three-year risk of cognitive impairment was compared across the clusters.

Results

We identified four clusters with distinct features in the derivation cohort. Cluster 1 was associated with the worst life independence, longest sleep duration, and the oldest age. Cluster 2 demonstrated the highest loneliness, characterised by non-marital status and living alone. Cluster 3 was characterised by the lowest sense of loneliness and the highest proportions in marital status and family co-residence. Cluster 4 demonstrated heightened engagement in exercise and leisure activity, along with independent decision-making, hygiene, and a diverse diet. In comparison to Cluster 4, Cluster 1 exhibited the highest three-year cognitive impairment risk (adjusted odds ratio (aOR) = 3.31; 95% confidence interval (CI) = 1.81-6.05), followed by Cluster 2 and Cluster 3 after adjustment for baseline MMSE, residence, sex, age, years of education, drinking, smoking, hypertension, diabetes, heart disease and stroke or cardiovascular diseases.

Conclusions

A data-driven approach can be instrumental in identifying individuals at high risk of cognitive impairment among cognitively normal elderly populations. Based on various sociodemographic features, these clusters can suggest individualised intervention plans.

The impact of diet quality on cognitive ability of Chinese older adults: evidence from the China Health and Nutrition Survey (CHNS)

BACKGROUND

Numerous studies have demonstrated a positive correlation between diet quality and cognitive performance, indicating that improving diet quality may be beneficial in preventing cognitive decline in older adults. However, few study has investigated the causal relationship between diet quality and cognitive performance. The purpose of this study is to evaluate the causal effects of diet quality on cognitive performance in Chinese adults aged 55 years and older. Particularly, we utilize the Chinese Diet Quality Index (CHEI), a dietary assessment tool tailored for Chinese populations, as a proxy for older adults' diet quality.

METHODS

Data were obtained from the China Health and Nutrition Survey (CHNS) ([Formula: see text], [Formula: see text]55 years old) conducted in 2004 and 2006. Cognitive function was tested by a subset of items from the Telephone Interview for Cognitive Status-Modified (TICS-m). Data on dietary intake was retrieved from three consecutive 24 hour recalls by participants and its quality was assessed by the 17-items Chinese Healthy Eating Index (CHEI). An Instrumental Variable technique was used to deal with the potential endogeneity of dietary quality. The instrumental variable used in our study is the community mean of CHEI.

RESULTS

After adjusting for socio-demographic factors (age, gender, education, per capita household income), lifestyle habits (smoking, alcohol consumption, physical activity, BMI), and chronic diseases (hypertension, diabetes), our findings revealed that improving diet quality had a significant positive effect on cognitive performance ([Formula: see text]), particularly in females aged 55-65 years ([Formula: see text]) and females with primary education and below ([Formula: see text]).

CONCLUSION

Our study suggests that improving diet quality and adhering to the Dietary Guidelines for Chinese may enhance cognitive performance in Chinese adults aged 55 years and older.

Atorvastatin mitigates memory deficits and brain monocyte infiltration in chronic hypercholesterolemia

Mild cognitive impairment (MCI) is a common symptom observed in people over 60 years old and is found to be aggravated by hypercholesterolemia. Severe neuroinflammation induced by BBB dysfunction and monocyte infiltration might be responsible for neuron damage and cognitive impairment. Atorvastatin is a lipid-lowering drug that is widely applied for the treatment of cardiovascular diseases. However, the potential function of Atorvastatin in hypercholesterolemia-induced MCI remains uncertain. Our research will explore the potential therapeutic function of Atorvastatin in memory deficits induced by chronic hypercholesterolemia. ApoE-/- mice were utilized to mimic the state of chronic hypercholesterolemia and were divided into four groups. Animals in the WT and ApoE-/-groups were orally administered with normal saline, while WT mice in the Atorvastatin group and ApoE-/- mice in the ApoE-/-+ Atorvastatin group were orally administered with 10 mg/kg/day Atorvastatin. Markedly increased plasma cholesterol levels reduced RI in the long-term memory test and the spatial short-term memory test, declined mobility in the open field test, and downregulated PSD-95 and BDNF were observed in ApoE-/- mice, all of which were signally reversed by Atorvastatin. Moreover, the percentages of brain Ly6Chi CD45+ cells and CD3+ CD45+ cells, as well as the blood Ly6Chi CD45+ cells, plasma IL-12/IL-23 levels and IL-17 level were found notably increased in ApoE-/- mice, all of which were largely repressed by Atorvastatin. Lastly, the increased BBB permeability, decreased ZO-1 and occludin levels, and reduced KLF2 level were markedly abolished by Atorvastatin. Collectively, Atorvastatin mitigated memory deficits and brain monocyte infiltration in ApoE-/- mice.

Serum Vitamin D3 Concentration, Sleep, and Cognitive Impairment among Older Adults in China

BACKGROUND

Cognitive decline in older adults has become one of the critical challenges to global health. This study aims to examine both cross-sectional and longitudinal associations of levels of serum 25-hydroxyvitamin D3 (25(OH)D3) (briefed as VD3) concentration and sleep quality/duration, especially their interactions, with risk of cognitive impairment among older adults in China.

METHODS

We utilized a special subsample of adults aged 65-105 years (individuals = 3412, observations = 4816) from eight provinces in China derived from the 2011/2012 and 2014 waves of the Chinese Longitudinal Healthy Longevity Survey. Cognitive impairment was measured by the Mini-Mental State Examination scale. Sleep quality was classified as good versus fair/poor, and sleep duration was classified into short (<7 h), normal (≥7 but <9 h), and long (≥9 h). The VD3 concentration was divided into three levels: deficiency (VD3 < 25 nmol/L), insufficiency (25 nmol/L ≤ VD3 < 50 nmol/L), and sufficiency (VD3 ≥ 50 nmol/L). A wide set of covariates that include demographics, socioeconomic status, family support, health practice, and health conditions was adjusted for robust findings. Multilevel random intercept logit regression models were used to examine the cross-sectional associations between VD3, sleep, and cognitive impairment, whereas logit regression models were applied to investigate the longitudinal associations.

RESULTS

In the cross-sectional analyses, when all covariates were adjusted, VD3 sufficiency was significantly associated with a 33% lower risk of cognitive impairment compared with VD3 deficiency; good sleep quality was associated with 34% lower odds of cognitive impairment compared with fair/poor sleep quality; sleep hours were not associated with cognitive impairment, although a long sleep duration (≥9 h) was associated with 30% higher odds of being cognitively impaired when baseline health was not controlled. Interaction analyses reveal that VD3 sufficiency could help to additionally reduce the risk of cognitive impairment for good sleep quality and normal sleep hours. In the longitudinal analyses, the association of VD3 sufficiency remains significant, whereas sleep quality and sleep duration were not significant associates.

CONCLUSIONS

Good sleep quality, normal sleep hours, and VD3 sufficiency are positively associated with good cognitive function. VD3 sufficiency could enhance the associations between sleep and cognitive impairment.

The neutrophil-to-lymphocyte ratio is associated with mild cognitive impairment in community-dwelling older women aged over 70 years: a population-based cross-sectional study

Background

The neutrophil-to-lymphocyte ratio (NLR) is a marker of inflammation that can be obtained quickly, conveniently, and cheaply from blood samples. However, there is no research to explore the effects of sex and age on the relationship between the NLR and mild cognitive impairment (MCI) in community-dwelling older adults.

Methods

A total of 3,126 individuals aged over 60 years in Shanghai were recruited for face-to-face interviews, and blood samples were collected. MCI was assessed by the Mini-Mental State Examination (MMSE) and the Instrumental Activities of Daily Living (IADL) scale, and neutrophil count and lymphocyte counts were measured in fasting blood samples. The NLR was calculated by dividing the absolute neutrophil count by the absolute lymphocyte count.

Results

In females, the NLR in the MCI group was significantly higher than that in the cognitively normal group (2.13 ± 0.94 vs. 1.85 ± 0.83, p < 0.001) but not in men. Logistic regression showed that a higher NLR was an independent risk factor for MCI in women [odds ratio (OR) = 1.33; 95% confidence interval (CI) = 1.14-1.55]. In addition, the elevated NLR quartile was associated with an increased risk of MCI, especially in women older than 70 years (p value for trend = 0.012).

Conclusion

Compared with males, female MCI patients had a significantly higher NLR than cognitively normal controls. In addition, elevated NLR was found to be significantly associated with MCI risk in women older than 70 years. Therefore, elderly Chinese women with a higher NLR value may be the target population for effective prevention of MCI.

Sex differences in the association between sarcopenia and mild cognitive impairment in the older Korean population

BACKGROUND

A link between sarcopenia and cognitive function has been proposed and is supported by several investigations. Nevertheless, the sex-linked relationship between these two diseases has been scarcely investigated. This cross-sectional study investigated sex differences in the association between sarcopenia and mild cognitive impairment.

METHODS

We included all 286 participants aged 60 years or older with MCI who visited the Department of Neurology at Veterans Health Service Medical Center in South Korea from January to December 2021. The diagnosis of MCI was confirmed by two neurologists based on the participants' neuropsychological test scores. Diagnosis of sarcopenia was based on the algorithm of Asian Working Group for Sarcopenia (AWGS) 2019 including bioelectrical impedance analysis and handgrip strength, and cognitive function was assessed using Seoul Neuropsychological Screening Battery Core (SNSB-C) test.

RESULTS

Among the 286 participants, 171 and 112 were men and women. After adjustment for potential covariates including APOE genotype, in women participants, there were significant associations between diagnosis of sarcopenia and MCI (OR = 4.72, 95%CI [1.39-15.97]), while there was no significant relationship in men participants. In eight subdomains of SNSB-C, we also found that women participants with sarcopenia demonstrated a significant memory decline (OR = 3.21, 95%CI [1.01-10.19]) as compared with the reference women group without sarcopenia after adjusting all covariates mentioned above. No significant association between any SNSB-C subdomain and MCI was demonstrated in men participants.

CONCLUSIONS

We demonstrated that there was a different relationship between sarcopenia and MCI by sex and that sarcopenia may affect the cognitive subdomain differently by sex. These results imply that, with regard to cognitive function, maintaining muscle function and muscle mass might be more crucial for women than for men.

The factors associated with cognitive function among community-dwelling older adults in Taiwan

BACKGROUND

This research aimed to investigate the associations of anthropometric measurements, physiological parameters, chronic disease comorbidities, and social and lifestyle factors with cognitive function amongst community-dwelling older adults in Taiwan.

METHODS

This was an observational, cross-sectional study involving 4,578 participants at least 65 years old, recruited between January 2008 and December 2018 from the Annual Geriatric Health Examinations Program. Cognitive function was assessed using the short portable mental state questionnaire (SPMSQ). Multivariable logistic regression was done to analyze the factors associated with cognitive impairment.

RESULTS

Among the 4,578 participants, 103 people (2.3%) with cognitive impairment were identified. Associated factors were age (odds ratio (OR) = 1.16, 95% confidence interval (CI) = 1.13,1.20), male gender (OR = 0.39, 95% CI = 0.21,0.72), diabetes mellitus (DM) (OR = 1.70, 95% CI = 1.03, 2.82), hyperlipidemia (OR = 0.47, 95% CI = 0.25, 0.89), exercise (OR = 0.44, 95% CI = 0.34, 0.56), albumin (OR = 0.37, 95% CI = 0.15, 0.88), and high-density lipoprotein (HDL) (OR = 0.98, 95% CI = 0.97, 1.00). Whereas waistline, alcohol intake in recent six months, and hemoglobin was not significantly associated with cognitive impairment (all p > 0.05).

CONCLUSIONS

Our findings suggested that people with older age and a history of DM had a higher risk of cognitive impairment. Male gender, a history of hyperlipidemia, exercise, a high albumin level, and a high HDL level seemed to be associated with a lower risk of cognitive impairment amongst older adults.

Association between sarcopenia and cognitive function in older Chinese adults: Evidence from the China health and retirement longitudinal study

Background

Sarcopenia and cognitive impairment are the most common causes of disability in the aging population. The potential role of sarcopenia in the development of cognitive impairment remains poorly understood. A cross-sectional analysis was performed using nationally representative data to evaluate associations between sarcopenia and cognition in China.

Methods

We included 2,391 participants (35.63% female) who were at least 60 years of age in 2015 from the China Health and Retirement Longitudinal Study (CHARLS). Muscle strength, appendicular skeletal mass (ASM), and physical performance measurements, were measured to diagnose sarcopenia according to the Asian Working Group for Sarcopenia 2019 (AWGS2019). Cognitive function was assessed by 10 items in the Telephone Interview for Cognitive Status (TICS-10), delayed word recall, and graph drawing. Based on cognitive score tertiles, data were divided into three groups. Multiple linear and logistic regression models were used to assess the relationship between sarcopenia and cognition.

Results

The prevalence of possible sarcopenia was 27.16% for men and 27.46% for women. Cognitive decline was significantly associated with sarcopenia status (β = -0.88, p < 0.001) and negatively associated with components of sarcopenia in male group. The results remained consistent in male after further adjusting for creatinine, uric acid, blood sugar, etc. Low cognitive function in female was only associated with low muscle strength (β = -0.85, p = 0.02). In addition, participants with possible sarcopenia had greater risk of cognitive decline than those without sarcopenia (OR = 1.41; 95% CI: 1.06-1.87). However, the same association was not significant in female group.

Conclusion

We suggest that sarcopenia might be associated with cognition function, with possible sarcopenia being significantly associated with higher cognition risk in China population, which providing a further rationale for timely recognition and management of sarcopenia.

Mild cognitive impairment among rural-dwelling older adults in China: A community-based study

BACKGROUND

Epidemiological studies of mild cognitive impairment (MCI) and subtypes of MCI have rarely focused on rural residents in China.

METHODS

This population-based study included 5068 participants (age ≥60 years) who were living in rural communities. We defined MCI, amnestic MCI (aMCI), and non-amnestic MCI (naMCI) following the Petersen's criteria that integrated neuropsychological assessments with in-person clinical evaluations.

RESULTS

The overall prevalence of MCI, aMCI, and naMCI was 26.48%, 22.30%, and 4.18%, respectively. The prevalence of MCI increased with age. The adjusted odds ratio (OR) of MCI was 0.71 (95% confidence interval [CI] 0.61 to 0.82) for primary school (vs. illiteracy), 0.30 (0.24 to 0.39) for middle school or above, 1.35 (1.09 to 1.67) for being farmers, 0.65 (0.54 to 0.78) for alcohol consumption, 1.43 (1.20 to 1.70) for stroke history, and 1.14 (0.95 to 1.36) for any apolipoprotein E (APOE) ε4 allele (vs ε3/ε3).

CONCLUSIONS

MCI affects over one-fourth of rural older adults in China. Overall MCI was associated with demographic factors, non-alcohol consumption, and stroke, but not with APOE genotype and cardiometabolic factors.

The path to healthy ageing in China: a Peking University-Lancet Commission

Around the world, populations are ageing at a faster pace than in the past and this demographic transition will have impacts on all aspects of societies. In May 2020, the UN General Assembly declared 2021–2030 the Decade of Healthy Ageing, highlighting the importance for policymakers across the world to focus policy on improving the lives of older people, both today and in the future. While rapid population ageing poses challenges, China’s rapid economic growth over the last forty years has created space for policy to assist older persons and families in their efforts to improve health and well-being at older ages. As China is home to 1/5 of the world’s older people, China is often held up as an example for other middle-income countries. This Commission Report aims to help readers to understand the process of healthy ageing in China as a means of drawing lessons from the China experience. In addition, with the purpose of informing the ongoing policy dialogue within China, the Commission Report highlights the policy challenges on the horizon and draws lessons from international experience.

A nomogram incorporating red blood cell indices to predict post-stroke cognitive impairment in the intracerebral hemorrhage population

Background

Post-stroke cognitive impairment (PSCI) plagues 20–80% of stroke survivors worldwide. There is a lack of an easy and effective scoring tool to predict the risk of PSCI in intracerebral hemorrhage (ICH) patients. We aimed to develop a risk prediction model incorporating red blood cell (RBC) indices to identify ICH populations at risk of PSCI.

Methods

Patients diagnosed with ICH at the stroke center were consecutively enrolled in the study as part of the development cohort from July 2017 to December 2018, and of the validation cohort from July 2019 to February 2020. Univariable and multivariable analyses were applied in the development cohort to screen the patients for PSCI risk factors. Then, a nomogram based on RBC indices and other risk factors was developed and validated to evaluate its performance in predicting PSCI occurrence.

Results

A total of 123 patients were enrolled in the development cohort, of which 69 (56.1%) were identified as PSCI, while 38 (63.3%) of 60 patients in the validation cohort were identified as PSCI. According to the multivariate analysis, seven independent risk factors, including three RBC indices (hemoglobin, mean corpuscular volume, RBC distribution width), as well as age, education level, hematoma volume, and dominant-hemisphere hemorrhage were incorporated into the model. The nomogram incorporating RBC indices displayed good discrimination and calibration. The area under the receiver operating characteristic curve was 0.940 for the development cohort and 0.914 for the validation cohort. Decision curve analysis and clinical impact curve showed that the nomogram was clinically useful.

Conclusion

RBC indices are independent and important predictors of PSCI. A nomogram incorporating RBC indices can be used as a reasonable and reliable graphic tool to help clinicians identify high cognition impairment-risk patients and adjust individualized therapy.

The prevalence of mild cognitive impairment in Latin America and the Caribbean: a systematic review and meta-analysis

OBJECTIVES

The population of Latin America and Caribbean (LAC) is ageing rapidly, presenting the highest prevalence rates of dementia in the world. Mild cognitive impairment (MCI) is an intermediate condition between normal ageing, Alzheimer's disease, and related dementias. We conducted a systematic review to evaluate the prevalence of MCI in LAC countries and explore factors associated with MCI (i.e. age, sex/gender, and education).

METHOD

A database search was conducted in September 2020 using PubMed, Web of Science, Scopus, Lilacs, SciELO, EMBASE, and medRxiv for population- or community-based studies, published in English, Spanish, or Portuguese.

RESULTS

From 2,155 screened studies, we selected reports including subjects with a precise diagnosis of MCI. A total of 11 studies met the inclusion criteria, adding up to 20,220 participants in nine countries: Brazil, Mexico, Argentina, Colombia, Peru, Cuba, Dominican Republic, Venezuela, and Costa Rica. Estimates for all-type MCI prevalence ranged from 6.8% to 25.5% and amnestic MCI between 3.1% and 10.5%. Estimates differed by age and education, with oldest and lower-educated adults presenting higher MCI prevalence.

CONCLUSION

This first systematic review of the prevalence of MCI discusses the population strata with the highest potential to benefit from dementia risk reduction interventions in LAC countries.

Alcohol Consumption and Mild Cognitive Impairment: A Mendelian Randomization Study from Rural China

Alcohol consumption has been associated with the risk of mild cognitive impairment (MCI) in observational studies. The result is inconsistent and whether the association is causal remains unknown. To examine the causal effect of alcohol consumption on MCI in rural China, this study used a cross-sectional dataset that included 1966 observations collected in rural China, of which 235 observations’ genotyping were collected. All participants accepted the MCI evaluation using Mini-Cog and were asked about the participants’ alcohol consumption behavior. The causal effect of alcohol consumption on MCI was investigated by Mendelian randomization (MR) of genetic variation in the aldehyde dehydrogenase 2 (ALDH2 rs671) gene. The risk of MCI in Chinese rural areas was 43%. Alcohol consumption was causally associated with a higher risk of MCI under MR design. Parameter estimates of drinking or not (b = 0.271, p = 0.007, 95% CI = 0.073 to 0.469), drinking frequency during the past 30 days (b = 0.016, p = 0.003, 95% CI = 0.005 to 0.027), and the weekly ethanol consumption (b = 0.132, p = 0.004, 95% CI = 0.042 to 0.223) were all positive and statistically significant at the 5% level. In conclusion, there was a high risk of MCI in rural China, and alcohol consumption was causally associated with a higher risk of MCI.

Virtual reality-based targeted cognitive training program for Chinese older adults: A feasibility study

OBJECTIVE

To investigate the acceptance and tolerance of a targeted cognitive training program with virtual reality (VR) in Chinese older adults.

METHODS

We developed a VR-based program consisting of five games for cognitive training. Fourteen older adults voluntarily participated in the VR training program from January 1 to 22, 2022. The tolerance of the participants and acceptance of the video-based training were assessed after training.

RESULTS

Of the participants, 8 (57.1%) had normal cognitive function, and 6 (42.9%) had cognitive impairment. The participants tolerated the program well with a total SSQ (simulated sickness questionnaire) score of 10.42±12.97. Regarding acceptance, 97.6% of subjects found VR equipment to be easy to use, 76.2% said it was a positive experience, and 57.1% thought VR devices were attractive.

CONCLUSION

This study shows that VR-based cognitive training was well tolerated by Chinese older adults, without major or severe adverse events.

Path Analysis Reveals the Direct Effect of PCB28 Exposure on Cognitive Dysfunction in Older Chinese Females

Background: Research indicates that exposure to polychlorinated biphenyls (PCBs) can cause neurobehavioral impairments in neonates and adults, but the way specific PCBs’ congeners impact cognition functions at a low exposure level in a real-life co-exposure system remains poorly understood. This study aimed to investigate the association of PCBs burden with cognition function among elderly adults. Methods: Based on the Weitang Geriatric Diseases study (2014−2015), the current study measured the plasma concentrations of six indicator-PCBs by GC-MS/MS and assessed the cognitive dysfunction (CoD) via an Abbreviated Mental Test in 266 participants (ages 61−90). Sequential logistic regression was used to analyze the effects of PCBs on cognition functions. Female participants aged less than or equal to 80 years were selected, and path analysis was used to determine the direct or indirect impacts of co-exposure PCBs on CoD by structural equation modeling. Results: After sequential adjustments to potential confounding factors and correction by the Bonferroni, no statistically significant correlation between PCBs exposure and CoD was found in participants (p > 0.05). However, in the co-exposure system, after controlling for co-exposures and confounders, exposure to PCB28 had a direct effect on CoD in females aged between 61 and 80, with a factor load of 0.670. Conclusions: After adjusting for the co-exposures and confounders, exposure to PCB28 can directly increase the risk of cognitive impairment in older Chinese females.

Risk of conversion from mild cognitive impairment to dementia in low- and middle-income countries: A systematic review and meta-analysis

Introduction

With no treatment for dementia, there is a need to identify high risk cases to focus preventive strategies, particularly in low‐ and middle‐income countries (LMICs) where the burden of dementia is greatest. We evaluated the risk of conversion from mild cognitive ompairment (MCI) to dementia in LMICs.

Methods

Medline, Embase, PsycINFO, and Scopus were searched from inception until June 30, 2020. The search was restricted to observational studies, conducted in population‐based samples, with at least 1 year follow‐up. There was no restriction on the definition of MCI used as long as it was clearly defined. PROSPERO registration: CRD42019130958.

Results

Ten thousand six hundred forty‐seven articles were screened; n = 11 retained. Of the 11 studies, most were conducted in China (n = 7 studies), with only two studies from countries classified as low income. A qualitative analysis of n = 11 studies showed that similar to high‐income countries the conversion rate to dementia from MCI was variable (range 6.0%–44.8%; average follow‐up 3.7 years [standard deviation = 1.2]). A meta‐analysis of studies using Petersen criteria (n = 6 studies), found a pooled conversion rate to Alzheimer's disease (AD) of 23.8% (95% confidence interval = 15.4%–33.4%); approximately one in four people with MCI were at risk of AD in LMICs (over 3.0–5.8 years follow‐up). Risk factors for conversion from MCI to dementia included demographic (e.g., age) and health (e.g., cardio‐metabolic disease) variables.

Conclusions

MCI is associated with high, but variable, conversion to dementia in LMICs and may be influenced by demographic and health factors. There is a notable absence of data from low‐income settings and countries outside of China. This highlights the urgent need for research investment into aging and dementia in LMIC settings. Being able to identify those individuals with cognitive impairment who are at highest risk of dementia in LMICs is necessary for the development of risk reduction strategies that are contextualized to these unique settings.

Herth Hope Index: A Psychometric Evaluation Study within a Sample of Greek Patients with Cancer

Objectives:

This study aims to develop the Greek version of the Herth Hope Index (HHI) and assess its psychometric properties to a palliative care patient sample, using a cross-sectional design.

Materials and Methods:

The HHI was translated into Greek (HHI-Gr) using the ‘forward-backward’ procedure. It was administered to 130 eligible cancer patients, while for the stability of patients’ responses, 40 of these patients completed the HHI-Gr 3 days later. Along with the HHI-Gr, patients also completed the Hospital Anxiety and Depression Scale (HADS) and the Beck Hopelessness Scale (BHS). The HHI-Gr internal consistency reliability (Cronbach’s a), stability (intraclass correlation coefficient [ICC]), factor structure (factor analysis) and convergent validity (correlation with the HADS and the BHS questionnaires) were examined using the Eastern Cooperative Oncology Group (ECOG) performance status.

Results:

The HHI-Gr yielded a one-factor model and a Cronbach alpha (0.860) with excellent internal consistency reliability and stability ICC (>0.90). Satisfactory convergent validity was supported by the correlation analysis between the HHI-Gr and BHS (r = 0.718, P < 0.001). Overall test-retest reliability was satisfactory with a range between 0.77 and 0.96 (P < 0.001).

Conclusion:

These results demonstrate that the HHI-Gr is an instrument with satisfactory psychometric properties and is a valid research tool for the measurement of the levels of hope among Greek oncology patients.

Design and evaluation of a cognitive health education pilot program according to the RE-AIM framework

OBJECTIVE

Most formats of currently used community-based health education for cognitive impairment prevention are limited to one-way communication, such as distributing leaflets, pasting posters, or holding a lecture, and they lack comprehensive evaluation. Here we aim to design, test, and evaluate a novel pilot cognitive health education program combined with psychosocial interventions (CHECPI).

METHODS

We designed the CHECPI program and tested it among adults aged 60 and over in an aging-friendly community in 2018. Multidimensional cognitive functions were measured by the Montreal Cognitive Assessment (MoCA) before and three months after the CHECPI program. Quantitative and qualitative analyses were performed based on the RE-AIM (Reach, Effectiveness, Adoption, Implementation, and Maintenance) framework to evaluate the program. Wilcoxon signed-rank tests were used to assess changes in multidimensional cognitive functions.

RESULTS

The CHECPI program was comprised of 12 courses and introduced 5 kinds of psychosocial interventions. Reach: 28 older adults participated in the program, of whom most were female (n = 22) and younger elderly with an average age of 65.32 years. Effectiveness: 19 participants finished≥6 courses as well as the follow-up survey. Although their MoCA scores did not improve significantly, they had increased their visuospatial ability significantly (with the average score increasing by 0.42). Adoption: the community officers, lecturers, and participants highly recommended the program, but they agreed that the lack of professional instructors may hinder its popularization. Implementation: the program was implemented in full accordance with the pre-program design. Maintenance: three months after the program, 17 participants had maintained at least one of the seven healthy behaviors that were introduced in the program.

CONCLUSIONS

Younger female elderly were more willing to participate in the program. It enhanced participants' visuospatial ability, but a sufficient number of professional instructors are crucial for large-scale promotion.

Cognitive Function Among Noncustodial Grandparents in China and the United States: A Cross-National Perspective

The current study aimed to investigate the association between grandparenting and cognitive function over time in noncustodial grandparents in China and the United States. Lagged dependent variable (LDV) approach and linear regression models were applied to analyze a sample of 1,411 Chinese and 6,579 American adults aged 65 and above from the China Health and Retirement Longitudinal Study (CHARLS, 2011-2013) and the U.S. Health and Retirement Study (HRS, 2012-2014). Grandparenting involvement was associated with less decline in episodic memory for grandparents and greater level of grandparenting had no negative effect on mental status and global cognitive function in noncustodial grandparents in China and the United States. The impact of grandparenting on cognitive function was conditioned on caregiving intensity, gender, urban/rural residence, and nation. Findings of the study suggest that greater attention on grandparenting facilitation might yield improved research, social support, policy, and interventions on cognitive health for the general older population.

Relationships between sarcopenia, depressive symptoms, and mild cognitive impairment in Chinese community-dwelling older adults

BACKGROUND

Mild cognitive impairment (MCI) represents an intermediate state between normal cognitive aging and dementia. We aimed to investigate the association and mediation pathways of sarcopenia, including its individual components (muscle mass, muscle strength, and physical performance), and depressive symptoms with MCI in the older adults.

METHODS

This study consisting of 1394 community-dwelling Chinese older adults aged 60 years and older in Tianjin and Shanghai, China. Sarcopenia was defined according to the Asian Working Group for Sarcopenia (AWGS) criteria. Depressive symptoms were evaluated by the 30-item Geriatric Depression Scale (GDS). Cognitive function was assessed by Mini-Mental State Examination (MMSE), the Chinese version of the Dementia Rating Scale (CDRS) was used to apply the diagnostic of non-dementia, and instrument activities of daily living (IADL) were used to evaluate daily living activities. Logistic regression and mediation analyses fully adjusted for all potential confounding factors were conducted.

RESULTS

Sarcopenia, handgrip strength, gait speed, and depressive symptoms were associated with MCI. Furthermore, depressive symptoms significantly mediated the association of sarcopenia, handgrip strength, and gait speed with cognitive function. The relationship of depressive symptoms and cognition were also mediated by sarcopenia, handgrip strength, and gait speed.

LIMITATIONS

This is a cross-sectional study.

CONCLUSIONS

Our findings suggest that sarcopenia may contribute substantially to the development of MCI in the older adults via depressive symptoms, although the reverse may also be true. These findings may help guide clinicians to better diagnose and manage MCI in the context of concomitant sarcopenia and depressive symptoms.

Body mass index and mild cognitive impairment among rural older adults in China: the moderating roles of gender and age

BACKGROUND

Evidence concerning the association between body mass index (BMI) and cognitive function among older people is inconsistent. This study aimed to investigate gender and age as moderators in association between BMI and mild cognitive impairment (MCI) among rural older adults.

METHODS

Data were derived from the 2019 Health Service for Rural Elderly Families Survey in Shandong, China. In total, 3242 people aged 60 years and above were included in the analysis. Multilevel mixed-effects logistic regression was used to examine the moderating roles of gender and age, then further to explore the relationship between BMI and MCI.

RESULTS

There were 601 (18.5%) participants with MCI. Compared with normal BMI group, low BMI group had a higher risk of MCI among older people [adjusted odds ratio (aOR) = 2.08, 95% confidence interval (CI): 1.26-3.44], women (aOR = 2.06, 95% CI: 1.35-3.12), or the older elderly aged ≥75 years old (aOR = 3.20, 95% CI: 1.34-7.45). This effect remained statistically significant among older women (aOR = 3.38, 95% CI: 1.69-6.73). Among older men, elevated BMI group had a higher risk of MCI (aOR = 2.32, 95% CI: 1.17-4.61) than normal BMI group.

CONCLUSIONS

Gender and age moderated the association between BMI and MCI among Chinese rural older adults. Older women with low BMI were more likely to have MCI, but older men with elevated BMI were more likely to have MCI. These findings suggest rural community managers strengthen the health management by grouping the weight of older people to prevent the risk of dementia.

Prevalence and Risk of Mild Cognitive Impairment in Low and Middle-Income Countries: A Systematic Review

Background: Mild cognitive impairment (MCI) is a cognitive state associated with increased risk of dementia. Little research on MCI exists from low-and middle-income countries (LMICs), despite high prevalence of dementia in these settings. Objective: This systematic review aimed to review epidemiological reports to determine the prevalence of MCI and its associated risk factors in LMICs. Methods: Medline, Embase, and PsycINFO were searched from inception until November 2019. Eligible articles reported on MCI in population or community-based studies from LMICs and were included as long as MCI was clearly defined. Results: 5,568 articles were screened, and 78 retained. In total, n = 23 different LMICs were represented; mostly from China (n = 55 studies). Few studies were from countries defined as lower-middle income (n = 14), low income (n = 4), or from population representative samples (n = 4). There was large heterogeneity in how MCI was diagnosed; with Petersen criteria the most commonly applied (n = 26). Prevalence of amnesic MCI (aMCI) (Petersen criteria) ranged from 0.6%to 22.3%. Similar variability existed across studies using the International Working Group Criteria for aMCI (range 4.5%to 18.3%) and all-MCI (range 6.1%to 30.4%). Risk of MCI was associated with demographic (e.g., age), health (e.g., cardio-metabolic disease), and lifestyle (e.g., social isolation, smoking, diet and physical activity) factors. Conclusion: Outside of China, few MCI studies have been conducted in LMIC settings. There is an urgent need for population representative epidemiological studies to determine MCI prevalence in LMICs. MCI diagnostic methodology also needs to be standardized. This will allow for cross-study comparison and future resource planning.

Prevalence of mild cognitive impairment in community-dwelling Chinese populations aged over 55 years: a meta-analysis and systematic review

Background

Mild cognitive impairment (MCI) is an intermediate phase between normal cognitive ageing and overt dementia, with amnesic MCI (aMCI) being the dominant subtype. This study aims to synthesise the prevalence results of MCI and aMCI in community-dwelling populations in China through a meta-analysis and systematic review.

Methods

The study followed the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) protocol. English and Chinese studies published before 1 March 2020 were searched from ten electronic bibliographic databases. Two reviewers screened for relevance of the studies against the pre-defined inclusion and exclusion criteria and assessed the quality of the included studies using the Risk of Bias Tool independently. A random-effect model was adopted to estimate the prevalence of MCI and aMCI, followed by sub-group analyses and meta-regression. Sensitivity and publication bias tests were performed to verify the robustness of the meta-analyses.

Results

A total of 41 studies with 112,632 participants were included in the meta-analyses. The Chinese community-dwelling populations over 55 years old had a pooled prevalence of 12.2% [95% confidence interval (CI): 10.6, 14.2%] for MCI and 10.9% [95% CI, 7.7, 15.4%] for aMCI, respectively. The prevalence of MCI increased with age. The American Psychiatric Association’s Diagnostic tool (DSM-IV) generated the highest MCI prevalence (13.5%), followed by the Petersen criteria (12.9%), and the National Institute on Aging Alzheimer’s Association (NIA-AA) criteria (10.3%). Women, rural residents, and those who lived alone and had low levels of education had higher MCI prevalence than others.

Conclusion

Higher MCI prevalence was identified in community-dwelling older adult populations in China compared with some other countries, possibly due to more broadened criteria being adopted for confirming the diagnosis. The study shows that aMCI accounts for 66.5% of MCI, which is consistent with findings of studies undertaken elsewhere.

Systematic review registration number

PROSPERO CRD42019134686.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-020-01948-3.

Diagnostic accuracy of early cognitive indicators in mild cognitive impairment

The aging of the population leads to an increase in the prevalence of dementia and mild cognitive impairment (MCI). Alzheimer's disease (AD) is the most common cause of dementia. Recent studies highlight the early non-amnestic deficits in AD and MCI. The European Union report shows the importance of thoroughly assessing cognitive aspects that have been poorly evaluated, such as processing speed (PS), which could represent early indicators of cognitive decline.

Objective

To analyze the diagnostic accuracy of PS measures in older adults with MCI, AD, and those who are cognitively-healthy.

Methods

A cross-sectional study was conducted by performing an extensive neuropsychological assessment in three samples: 26 control participants, 22 individuals with MCI, and 21 individuals with AD. Analysis of variance (ANOVA) was employed to test the relationship between dependent variables and the clinical group. Post hoc tests (Bonferroni test) were used when a significant ANOVA result was found. Finally, the Receiver Operating Characteristic (ROC) curve for PS measures was performed in older adults with MCI and AD compared with cognitively-healthy older adults.

Results

The results showed that deficits in PS measures can be early indicators of cognitive decline in cases of MCI, even when executive functions (EFs) and functionality are preserved. Conversely, AD versus MCI presented differences in PS, EFs, and functionality.

Conclusions

The ROC analyses showed that PS measures had discriminative capacities to differentiate individuals with MCI, AD, and cognitively-healthy older adults.

Childhood Friendship Experiences and Cognitive Functioning in Later Life: The Mediating Roles of Adult Social Disconnectedness and Adult Loneliness

BACKGROUND AND OBJECTIVES

This study investigated the relationship between childhood friendships and cognitive functioning, as assessed with cognitive status and decline among adults aged 45 and older in China. We also examined the mediating effect of adult social disconnectedness and adult loneliness for this relationship.

RESEARCH DESIGN AND METHODS

This study was based on 3 waves of data from the China Health and Retirement Longitudinal Study (CHARLS; 2011, 2013, 2015; N = 13,959). Cognitive functioning was assessed with episodic memory. Childhood friendship measures were taken from the 2014 life history module of the CHARLS. Two dimensions of adult social isolation, loneliness and social disconnectedness, were included as mediators. Latent growth curve modeling was utilized to test the associations between childhood friendships, adult social isolation, and cognitive functioning.

RESULTS

Adverse childhood friendship experiences were found to be significantly associated with both lower initial cognitive status and the rate of decline in cognitive functioning. Our findings indicated that adult loneliness and social disconnectedness partly mediated the link between childhood friendship experiences and the initial level of cognitive functioning, but not cognitive decline later in life.

DISCUSSION AND IMPLICATIONS

The findings emphasized the enduring importance of childhood friendships for cognitive functioning later in life. Interventions that focus on improving social participation through fostering friendships in childhood may have long-term benefits for cognition later in life.

Age- and Sex-Specific Prevalence and Modifiable Risk Factors of Mild Cognitive Impairment Among Older Adults in China: A Population-Based Observational Study

Background

Minimal data are available on the prevalence of mild cognitive impairment (MCI) in older Chinese adults. Moreover, the current information on MCI shows important geographical variations.

Objective

We aimed to assess the prevalence and risk factors for MCI by age and sex among older adults in a North Chinese population.

Methods

In this population-based cross-sectional study, we enrolled a random sample of 4,943 adults aged ≥ 60 years between March 2018 and June 2019 in Tianjin, China. Of these, 312 individuals were excluded due to a lack of data (e.g., fasting blood test). As a result, 4,631 subjects were assessed. Individuals with MCI were identified using neuropsychological assessments, including the Mini-Mental State Examination and Activities of Daily Living scale, based on a modified version of the Petersen’s criteria.

Results

The mean (SD) age of the 4,631 participants was 67.6 (4.89) years, and 2,579 (55.7%) were female. The overall age- and sex-standardized prevalence of MCI in our study population was 10.7%. There were significant associations of MCI with age [65–69 vs. 60–64 years, OR = 0.74; 95% confidence interval (CI): 0.58, 0.96], physical activity (≥23.0 vs. <23.0 MET-hours/week, OR = 0.79; 95% CI: 0.64, 0.96), body mass index (BMI) (OR = 0.92; 95% CI: 0.89, 0.95), grip strength (OR = 0.50; 95% CI: 0.38, 0.67), hypertension (yes vs. no, OR = 1.44; 95% CI: 1.18, 1.77), higher levels of sleepiness (OR = 1.80; 95% CI: 1.36, 2.37), and longer sleep duration (OR = 1.40; 95% CI: 1.14, 1.72). The inverse association between BMI and MCI was stronger in older age groups (P for heterogeneity = 0.003). Moreover, the magnitude of association between triglycerides and MCI was different between the sexes (P for heterogeneity = 0.029).

Conclusion

The age- and sex-standardized prevalence of MCI was 10.7% in the study sample. Physical activity, BMI, grip strength, sleepiness, sleep duration, and hypertension were associated with the prevalence of MCI. Additionally, triglycerides and BMI might be differently associated with the presence of MCI for different sexes and age stages, respectively.

Living With Cognitive Impairment in China: Exploring Dyadic Experiences Through a Person-Centered Care Lens

China has experienced a substantial increase in the number of older adults with dementia and milder forms of cognitive impairment. Being spouses of Persons with cognitive impairment (PWCI) and living with them for several decades does not necessarily mean that it is easier for them to provide person-centered care and maintain a valued and healthy relationship. The current study explored how elements of PCC, as operationalized by the Senses Framework, operate or fail to operate in the dyadic experiences of PWCI and their spousal care partners within the socio-cultural context of China. Our findings suggest that PWCI and their spouses experience the six senses through the person-centeredness in their daily interactions with each other. It also indicated successes and challenges to being person-centered early in the disease and identified their unmet needs as well as barriers and facilitators to improve their well-being.

Sex- and age-specific mild cognitive impairment is associated with low hand grip strength in an older Chinese cohort

Background

Few studies have demonstrated the impact of characteristics like age and sex on the association between hand grip strength (HGS) and mild cognitive impairment (MCI). In this cross-sectional study, we aimed to examine the effects of sex and age on the relationship between HGS and MCI.

Methods

We enrolled older adults age ≥60 years (n = 1009) and measured HGS and MCI in all participants. We analyzed the differences in MCI prevalence among the different variables. The role of sex and age in the association between MCI and HGS was analyzed using binary logistic regression.

Results

Women had significantly higher prevalence of MCI than men, as did the older group (age ≥70 years) compared with the younger group (age 60–70 years). In men, the low and middle HGS tertiles were significantly associated with MCI. In contrast, only the low tertile of HGS was associated with MCI in women. In the older group, the low tertile of HGS was significantly associated with MCI, which was not observed in the younger group.

Conclusions

HGS was associated with MCI in older adults, and this association was stronger in men. HGS may be useful for evaluating MCI in older adults.

The power of weak ties in preserving cognitive function: a longitudinal study of older Chinese adults

Objectives: Characterized by infrequent contact, low emotional intensity, and limited intimacy, weak ties are found to be associated with better subjective well-being and other health outcomes. Drawing on the theory of weak ties and the convoy model of social relations, this paper aims to examine the association between weak ties and cognitive function among older adults in China.Methods: We used multilevel growth modeling to analyze panel data for adults aged 60 years and over (N = 2,650) selected from the China Health and Retirement Longitudinal Study (CHARLS, 2011-2015). Weak ties were measured based on the frequency of social activity participation and the number of social activities.Results: Weekly or irregular social activity participation in at least one social activity was significantly associated with better mental status and memory. The number of participated social activities was also significantly and positively associated with mental status and memory. After controlling for age, gender, marital status, educational attainment, geographic residence, household expenditures, and health conditions (i.e., depressive symptoms and self-reported health), we found that participation in a greater number of social activities protected memory from declining by 4% for every 2 years (p < 0.001).Conclusion: These findings suggest that social interactions with peripheral members of a diverse social network may help prevent cognitive decline for older Chinese adults. Greater attention on weak ties might yield practical implications for non-pharmacological dementia prevention and health promotion for the general older population.

A qualitative study of family caregivers' coping strategies of looking after people with dementia in China

Background and aims

Globally, two thirds of people with dementia are cared for by their families or friends. Family caregivers' coping strategies of managing the caregiving burden of dementia have been studied widely in western literature. However, few attempts have been made to explore the experience of family caregivers' coping strategies in China. The aim of this study was to explore the family caregivers' coping strategies when caring for people with dementia in one city in the province of Shandong, China.

Methods

Fourteen family caregivers were individually interviewed, and interpretative phenomenological analysis was used to identify themes within different family members.

Results

Four key themes were found: (a) being filial; (b) changing self and self-care; (c) seeking help; and (d) having hope and continuing life.

Conclusion

The study illustrates the different strategies developed by family members in order to cope with their new roles when caring for a relative who has dementia. It shows that cultural belief of filial piety plays a large role across these various coping strategies. It highlights how responsibility has been maintained and influenced by the specific sociocultural context. The results provide a useful foundation for developing interventions that support family caregivers cope with the burden of caring in this population.

Hearing loss and cognitive function among Chinese older adults: the role of participation in leisure activities

BACKGROUND

Hearing loss, a highly prevalent sensory impairment affecting older adults, is a risk factor for cognition decline. However, there were very limited studies on this association in low-resource countries. This study aimed to assess the association between self-reported hearing loss and cognitive decline, and whether engagement in leisure activities moderated this association among older adults in China.

METHODS

Data were obtained from two waves of the nationally representative survey of China Longitudinal Healthy Longevity Survey (CLHLS) between 2011/12-2014. Eight thousand eight hundred forty-four individuals aged 65 years old or above with a dichotomized measure of self-reported hearing status were included. Modified Mini-Mental Examination (MMSE) was used to measure global cognition. Fixed-effects models were used to estimate whether leisure activity engagement moderated the association of self-perceived hearing loss with global cognitive change in the overall sample and sex subsamples.

RESULTS

Self-reported hearing loss was associated with cognitive impairment, with an odds ratio of 2.48 [1.22, 5.06]. Sex difference in the association of hearing loss and cognitive impairment was not found. Self-reported hearing loss was associated with cognitive decline, with 8% increase in risk compared with those with normal hearing. Frequent engagement in leisure activities moderated the association between hearing loss and cognitive decline for the whole and male samples.

CONCLUSION

Hearing loss was associated with cognitive decline, and leisure activities engagement moderated the association among males rather than females.

The mediating effect of psychological distress on cognitive function and physical frailty among the elderly: Evidence from rural Shandong, China

BACKGROUND

Few studies have explored the underlying mechanism between physical frailty and cognitive function. The aim of this study is to explore the mediating role of psychological distress (PD) for the association between cognitive function and physical frailty among the elderly in rural China.

METHODS

A total of 3,242 rural older adults were included in the analysis. Logistic regression and Bootstrap analyses were employed to explore the association between cognitive function, PD and frailty, and the mediating role of PD.

RESULTS

This study found that the prevalence of frailty and cognitive impairment among the elderly in rural China was 18.0%, 22.4%. After adjusted for controlling variables, cognitive function was significantly associated with high level of PD, and elderly with higher level of PD had a higher probability of suffering from frailty. PD played a partially mediating effect in cognitive function and frailty and the mediating effect of PD can explain the 11.0% of the total effect of cognitive function on frailty.

LIMITATIONS

The data were cross-sectional, thus the causal relationship between variables could not be determined. The main variables in this study were measured by self-report information, which might result in recall bias.

CONCLUSIONS

This study provide evidence that the effect of cognitive function on physical frailty was partially mediated by PD among the elderly in rural China. Primary health care should strengthen the screening of PD characterized by depression and anxiety, and strive to improve the physical and psychological well-being of rural elderly in China.

Both short and long sleep durations are associated with cognitive impairment among community-dwelling Chinese older adults

This study aims to examine the association between sleep duration and cognitive impairment in community-dwelling Chinese older adults.The associations between sleep duration and cognitive function have been widely studied across various age ranges but are of particular importance among older adults. However, there are inconsistent findings regarding the relationship between sleep duration and cognitive function in the literature.This study is an observational cross-sectional study. We analyzed data from 1115 Chinese individuals aged 60 and older from 3 Chinese communities (Beijing, Hefei, and Lanzhou). Cognitive impairment was defined as a Mini-Mental State Examination total score less than 24 points. Odds ratios (ORs) of associations were calculated and adjusted for potential confounders in logistic regression models.The prevalence of cognitive impairment was 25.7% (n = 287). Controlling for all demographic, lifestyle factors, and coexisting conditions, the adjusted OR for cognitive impairment was 2.54 (95% CI = 1.70-3.80) with <6 hours sleep and 2.39 (95% CI = 1.41-4.06) with >8 hours sleep.Both short and long sleep durations were related to worse cognitive function among community-dwelling Chinese elderly adults.

Prospective associations between depressive symptoms and cognitive functions in middle-aged and elderly Chinese adults

OBJECTIVE

To examine prospective associations of clinically relevant depressive symptoms with cognitive functions and rates of cognitive decline among Chinese adults aged 45 years and older.

METHODS

Data was from the China Health and Retirement Longitudinal Study (CHARLS) with a follow-up of 4 years. Based on the Chinese version of 10-item Center for Epidemiologic Studies Depression Scale (CESD-10), clinically relevant depressive symptoms were defined with a CESD-10 score≥10 points. Cognitive functions were measured in three domains: episodic memory, mental status and global cognition. Linear mixed models were used to assess the associations between clinically relevant depressive symptoms and cognitive functions.

RESULTS

A total of 7335 participants (50.10% men; mean age: 57.47) were included in analyses. Participants with clinically relevant depressive symptoms showed poorer episodic memory (β=-0.35; 95% CI:-0.41, -0.29), mental status (β=-0.48; 95% CI: -0.57, -0.39), and global cognition (β=-0.82; 95% CI: -0.94, -0.70) during the follow-up. Compared with counterparts, rates of decline in episodic memory, mental status, and global cognition increased by 0.04 (β=0.04; 95% CI: 0.02, 0.06), 0.06 (β=0.06; 95% CI: 0.02, 0.09) and 0.11 (β=0.11; 95% CI: 0.06, 0.15) units per year in participants with clinically relevant depressive symptoms.

LIMITATIONS

A major limitation is that clinically relevant depressive symptoms were assessed by a screening tool and the follow-up was short.

CONCLUSION

More severe clinically relevant depressive symptoms were associated with poorer cognitive functions and moderately faster cognitive decline in episodic memory, mental status and global cognition in middle-aged and elderly Chinese adults.

Hypothetical Interventions on Risk Factors for Cognitive Impairment among Chinese Older Adults: An Application of the Parametric G-Formula

The effects of psychosocial and dietary interventions on risk of cognitive impairment is not known. The aim of this study was to estimate the 10-year risks of cognitive impairment under hypothetical interventions of psychosocial factors and dietary intake among Chinese older adults. A sample of 7377 respondents aged 65 and over was drawn from the last four waves of the Chinese Longitudinal Healthy Longevity Survey from 2002 to 2011/2012. The parametric g-formula was used to estimate the risk of cognitive impairment under independent hypothetical interventions of social engagement, psychological well-being (PWB), dietary intake, and the joint interventions of their different combination. The observed risk of cognitive impairment was 20.08% (95% confidence interval (CI): 18.81, 21.07). The risk ratios (RR) of cognitive impairment under the hypothetical interventions on higher social engagement, eating fruits at least sometimes, eating vegetables at least sometimes, positive PWB were 0.72 (95% CI: 0.65, 0.82), 0.93 (95% CI: 0.89, 0.95), 0.98 (95% CI: 0.89, 1.00) and 0.99 (95% CI: 0.98, 0.99), respectively. The RR of joint intervention was 0.64 (95% CI: 0.58, 0.73). Hypothetical interventions on psychosocial factors such as social engagement and PWB, as well as fruits and vegetable intake, were beneficial to protect older adults from cognitive impairment.

Non-communicable Diseases and Cognitive Impairment: Pathways and Shared Behavioral Risk Factors Among Older Chinese

Population aging has brought about a number of challenges to public health and primary health care systems due to increases in the prevalence of non-communicable diseases (NCDs). As a country with one of the largest populations globally, China is confronting a rising number of chronic NCDs including cardiometabolic related conditions. This mini-review investigates the link between NCDs and cognitive impairment through common risk factors. Identifying risk factors is important for the prevention and management of these chronic conditions. In addition, this review also identifies the role of primary health care services in reducing behavioral risk factors for NCDs and cognitive impairment. Addressing shared determinants and pathways is important in the design of public health interventions and primary health care services in China. Monitoring and management of NCD biomarkers and behavioral risk factors may also be beneficial for cognitive health among older Chinese.

Social Networks, Community Engagement, and Cognitive Impairment among Community-Dwelling Chinese Older Adults

Aims

To examine the association of social networks and community engagement with cognitive impairment among community-dwelling Chinese older adults.

Methods

From November 2017 to May 2018, we selected 1,115 elderly individuals from 3 Chinese communities (Beijing, Hefei, and Lanzhou) using a random-cluster sampling method, and recorded data on demographics, social network characteristics, community activities, and cognitive function. The odds ratios (ORs) of these associations were adjusted for potential confounders in logistic regression models.

Results

The prevalence of cognitive impairment was 25.7′ (n = 287). An adequate social network (OR 0.55; 95′ confidence interval [CI] 0.33–0.91) and enough social support from friends (OR 0.43; 95′ CI 0.29–0.62) were negatively associated with cognitive impairment. Family support was not significantly associated with cognitive impairment (OR 0.64; 95′ CI 0.34–1.21). Taking part in elderly group travel, communication with others using WeChat, and community activities such as Tai Chi and walking together were negatively associated with cognitive impairment.

Conclusion

Social network characteristics and community engagement were found to be related to cognitive function among community-dwelling Chinese elderly adults.

Dementia in China: epidemiology, clinical management, and research advances

China has the largest population of patients with dementia in the world, imposing a heavy burden on the public and health care systems. More than 100 epidemiological studies on dementia have been done in China, but the estimates of the prevalence and incidence remain inconsistent because of the use of different sampling methods. Despite improved access to health services, inadequate diagnosis and management for dementia is still common, particularly in rural areas. The Chinese Government issued a new policy to increase care facilities for citizens older than 65 years, but most patients with dementia still receive care at home. Western medicines for dementia symptoms are widely used in China, but many patients choose Chinese medicines even though they have little evidence supporting efficacy. The number of clinical trials of Chinese and western medicines has substantially increased as a result of progress in research on new antidementia drugs but international multicentre studies are few in number. Efforts are needed to establish a national system of dementia care enhance training in dementia for health professionals, and develop global collaborations to prevent and cure this disease.

Intergenerational financial exchange and cognitive impairment among older adults in China

Objective: This study investigated the relationship between intergenerational financial exchange patterns and cognitive impairment among older Chinese adults. The study also explored potential pathways linking financial exchanges to cognitive health. Method: Data were taken from the 2005 and 2008 Chinese Longitudinal Healthy Longevity Survey. Three patterns of financial exchange (i.e., low receiving, high receiving, and reciprocity) based on a latent profile analysis were examined as predictors. Logistic regression models were employed to analyze variation in the Chinese version of the mini-mental status exam, taking into consideration the financial exchange patterns and a set of covariates. Results: Older adults with a reciprocity exchange pattern with their adult children had a lower likelihood of being cognitively impaired, supporting our hypotheses drawn from social exchange theory. Nutrition was found to mediate the relationship between financial exchange and cognition. Discussion: The inclusion of adequate nutrition intake as a means of maintaining cognitive well-being may help communities and families, as well as older Chinese adults, promote well-being and live a higher quality of life.

Changes in Cognitive Function and Risk Factors for Cognitive Impairment of the Elderly in China: 2005-2014

Background: The cognitive function of the elderly has become a focus of public health research. Little is known about the changes of cognitive function and the risk factors for cognitive impairment in the Chinese elderly; thus, the purposes of this study are as follows: (1) to describe changes in cognitive function in the Chinese elderly from 2005–2014 and (2) to explore risk factors for cognitive impairment of the Chinese elderly. Design and setting: A total of 2603 participants aged 64 years and above participated in the Chinese Longitudinal Healthy Longevity Survey (CLHLS) and were followed up from 2005 to 2014. Cognitive function and cognitive impairment were assessed using the Chinese version of the Mini-Mental State Examination (MMSE). Binary logistic regression analysis was used to estimate the odds ratio (OR) and 95% confidence intervals (CI) of cognitive impairment. Results: Results revealed that the cognitive function of the Chinese elderly shows diversified changes: deterioration (55.09%), unchanged (17.21%) and improvement (27.70%). In addition, there are significant demographic differences in gender, age, education, marriage and other aspects when it comes to the changes of cognitive function in Chinese elderly. In the binary logistic regression analysis, female, increased age, lower education level, no spouse, less income, worse PWB (psychological well-being), less fresh fruit and vegetable intake, more activities of daily living (ADL) limitations, lower social engagement were significantly associated with higher odds for cognitive impairment. Conclusions: Various interventions should be implemented to maintain cognitive function in Chinese elderly.

Psychometric validation of Fuld Object Memory Evaluation in older adults with cognitive impairments

OBJECTIVES

Mild cognitive impairment (MCI) refers to an early but abnormal state of cognitive impairment with minimal functional impairment. The present study aimed to evaluate the validity of Fuld Object Memory Evaluation (FOME) as a measure of episodic memory function.

METHOD

The study sample included 204 Chinese older adults with cognitive impairments. The participants completed five recall trials and a delayed trial in FOME, neurocognitive measures on digit spans and trail making, and daily functioning. Discriminative power of FOME to differentiate between MCI and dementia was inspected via receiver operating characteristic curve analysis.

RESULTS

FOME showed good test-retest reliability and convergent validity with digit spans and trail making. Controlling for gender, age, and education, lower levels of FOME total retrieval, verbal fluency, and daily functioning significantly predicted a higher likelihood of dementia compared to MCI. The optimal cut-off scores for total retrieval, verbal fluency, and daily functioning to differentiate dementia were 37/38 (77% sensitivity and 83% specificity), 28/29 (85% sensitivity and 72% specificity), and 14/15 (92% sensitivity and 78% specificity), respectively, in the younger subgroup. The corresponding figures were 34/35 (69% sensitivity and 76% specificity) and 27/28 (92% sensitivity and 62% specificity), and 11/12 (74% sensitivity and 80% specificity), respectively, in the older subgroup.

CONCLUSION

The findings support the FOME as a valid assessment tool of episodic memory function in older Chinese adults. The combined use of FOME and daily functioning is recommended to distinguish persons with dementia from MCI.

Lifespan Intellectual Factors, Genetic Susceptibility, and Cognitive Phenotypes in Aging: Implications for Interventions

Along with rapid global population aging, the age-related cognitive disorders such as mild cognitive impairment (MCI) and dementia have posed a serious threat to public health, health care system, and sustainable economic and societal development of all countries. In this narrative review, we seek to summarize the major epidemiological studies from the life-course perspective that investigate the influence of genetic susceptibility [e.g., apolipoprotein (APOE) ε4 allele] and intellectual or psychosocial factors (e.g., educational attainments and leisure activities) as well as their interactions on cognitive phenotypes in aging. Numerous population-based studies have suggested that early-life educational attainments and socioeconomic status, midlife work complexity and social engagements, late-life leisure activities (social, physical, and mentally-stimulating activities), certain personality traits (e.g., high neuroticism and low conscientiousness), and depression significantly affect late-life cognitive phenotypes. Furthermore, certain intellectual or psychosocial factors (e.g., leisure activities and depression) may interact with genetic susceptibility (e.g., APOE ε4 allele) to affect the phenotypes of cognitive aging such that risk or beneficial effects of these factors on cognitive function may vary by carrying the susceptibility genes. Current evidence from the randomized controlled trials that support the cognitive benefits of cognitive training among cognitive healthy older adults remains limited. The cognitive reserve hypothesis has been proposed to partly explain the beneficial effects of lifetime intellectual and psychosocial factors on late-life cognitive function. This implies that, from a life-course perspective, preventive intervention strategies targeting multiple modifiable intellectual and psychosocial factors could interfere with clinical expression of cognitive disorders in old age and delay the onset of dementia syndrome, and thus, may help achieve healthy brain aging.

Association between Diabetes and Cognitive Function among People over 45 Years Old in China: A Cross-Sectional Study

Objectives: The aim of this study is to identify the relationship between diabetes status including characteristics of diabetes and cognition among the middle-aged and elderly population (≥45 years) in China. Methods: A sample of 8535 people who participated in the China Health and Retirement Longitudinal Study (CHARLS) from June 2011 to March 2012 was analyzed. Two cognitive domains including episodic memory and executive function were measured through questionnaires. People were classified into four groups: no diabetes, controlled diabetes, untreated diabetes, treated but uncontrolled diabetes. Weighted multiple regression model was conducted to explore the association between diabetes and cognition in full sample as well as three different age groups (45–59, 60–74, ≥75). Adjustments were made for demographics and cardiovascular risk factors. Results: After adjusting several covariates, untreated diabetes (β = −0.192, p < 0.05) was significantly associated with episodic memory. In the age group of 45–69 years, untreated diabetes (β = −0.471, p < 0.05) and HbA1c level (β = −0.074, p < 0.05) were significantly associated with episodic memory. When adjusting for cardiovascular risk factors, all correlations were non-significant. Conclusion: The cross-sectional study suggests that untreated diabetes and HbA1c are the potential risk factor for cognitive impairment, and these associations are more significant in the age group of 45–59 years old. Cardiovascular factors are important mediating factors in the pathway between diabetes and cognitive impairment. More longitudinal studies are needed to confirm these associations.

Cognitive tests for the detection of mild cognitive impairment (MCI), the prodromal stage of dementia: Meta-analysis of diagnostic accuracy studies

INTRODUCTION

Mild cognitive impairment (MCI) is regarded as a prodrome to dementia. Various cognitive tests can help with diagnosis; meta-analysis of diagnostic accuracy studies would assist clinicians in choosing optimal tests.

METHODS

We searched online databases for "mild cognitive impairment" and "diagnosis" or "screening" from 01/01/1999 to 01/07/2017. Articles assessing the diagnostic accuracy of a cognitive test compared with standard diagnostic criteria were extracted. Risk of bias was assessed. Bivariate random-effects meta-analysis was used to evaluate sensitivity and specificity.

RESULTS

Eight cognitive tests (ACE-R, CERAD, CDT-Sunderland, IQCODE, Memory Alteration Test, MMSE, MoCA, and Qmci) were considered for meta-analysis. ACE-R, CERAD, MoCA, and Qmci were found to have similar diagnostic accuracy, while the MMSE had lower sensitivity. Memory Alteration Test had the highest sensitivity and equivalent specificity to the other tests.

DISCUSSION

Multiple cognitive tests have comparable diagnostic accuracy. The Memory Alteration Test is short and has the highest sensitivity. New cognitive tests for MCI diagnosis should not be compared with the MMSE.