Incidence and predictors of mild cognitive impairment (MCI) within a multi-ethnic Asian populace: a community-based longitudinal study

Prevalence of mild cognitive impairment and its association with malnutrition in older Chinese adults in the community

Objective

This study aims to characterize the prevalence and associated factors of cognitive impairment in older adults within Chinese community settings.

Background

Research exploring the interrelation between malnutrition and cognitive impairment in the older adult community-dwelling population is scarce. The impact of nutritional status on cognitive function in aging adults has not been definitively established.

Methods

A cross-sectional survey was conducted in one urban and one rural community in Chengdu, China, from October 2022 to March 2023. The sample included 706 older adults. Logistic regression was utilized to determine independent risk factors for mild cognitive impairment (MCI).

Results

The study found a significant prevalence of MCI at 32.0% among the older adult population. Among those suffering from malnutrition, 55.6% were affected by MCI. The logistic regression analysis indicated that malnutrition risk (OR = 2.192, 95% CI 1.431 to 3.357, p < 0.001), rural residence (OR = 1.475, 95% CI 1.003 to 2.170, p = 0.048), age (70-79 years old; OR = 2.425, 95% CI 1.611 to 3.651, p < 0.001; ≥80 years old: OR = 4.773, 95% CI 2.571 to 8.859, p < 0.001), male (OR = 1.584, 95% CI 1.085 to 2.313, p = 0.017), middle education level (OR = 0.986, 95% CI 1.627 to 5.482, p < 0.001), and ADL dependence (OR = 1.810, 95% CI 1.158 to 2.827, p = 0.009) were significantly associated with the occurrence of MCI.

Conclusion

The findings indicate a widespread occurrence of MCI in community-dwelling older Chinese adults. The association between malnutrition, as measured by the Mini Nutritional Assessment-Short Form (MNA-SF), and cognitive decline is evident. Older adult individuals with nutritional risk, advancing age, rural residence, male gender, moderate education, and ADL dependency are at increased likelihood of developing MCI. Longitudinal research is needed to clarify the temporal relationships between MCI, demographic factors, and whether improvements in nutritional status or ADL can reduce the incidence of MCI in this population.

Modifiable risk factors for mild cognitive impairment among cognitively normal community-dwelling older adults: A systematic review and meta-analysis

Although numerous studies have investigated modifiable risk factors for mild cognitive impairment (MCI) among community-dwelling seniors, no meta-analysis has summarized these findings. Five databases were searched from January 1, 2000, to December 30, 2023. The protocol was registered with PROSPERO. Data were extracted and reported following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Relevant meta-analyses of modifiable risk factors were performed. The evidence of each factor was assessed by the GRADE for cohort studies. Of 16,651 citations, 87 studies involving 225,584 community-dwelling seniors were included. Fourteen meta-analyses involving 20 studies with 44,199 participants were performed. The analyses revealed low-to-moderate-quality evidence supporting that diabetes, 2 or more comorbidities, anxiety, apathy, depressive symptoms, and physical frailty were risk factors for incident MCI in older adults. Conversely, hypertension, agitation, and irritability might not be risk factors. Additionally, moderate-quality evidence supports the protective effect of engaging in cognitive-demanding activities on the onset of MCI. Collectively, this study constitutes the first extensive compilation of evidence regarding the various risk factors for the development of MCI in older adults. Our findings hold significant potential to guide the formulation of prevention and management strategies to either prevent or potentially reverse the onset of MCI.

Mapping the landscape: A bibliometric analysis of information and communication technology adoption by older adults with cognitive frailty or impairment

The adoption of information and communication technology (ICT) by older adults with cognitive frailty and impairment is beneficial to support aging in place and promote healthy aging. However, data are scarce regarding the use of ICT by this demographic in comparison with other age groups. This bibliometric analysis was aimed at systematically mapping the literature on ICT-related research on older adults with cognitive frailty and cognitive impairment to provide insights into research trends, patterns and knowledge gaps. Data were extracted from the Web of Science database, which identified 324 publications between 1980 and 2023. Performance analysis and science mapping were carried out using Microsoft® Excel, VOSViewer and Harzing's Publish or Perish. The analysis showed an upsurge in the research output trend over time. Notable journals, authors, citations, nations and research areas have been documented. Four key clusters were identified, including: (i) caregiver concern, support and involvement; (ii) technology as a tool for cognitive training and cognitive rehabilitation; (iii) cognitive improvement; and (iv) the use of technology for prevention and self-management. The findings derived from this analysis provide an appropriate reference for future researchers to bridge the gap in ICT-related studies among this population, and distinguish the relevant articles that are required for further investigation. These include the need for further long-term research, the incorporation of ICT-based approaches to counter cognitive frailty and the importance of multidomain telehealth interventions. Geriatr Gerontol Int 2024; 24: 251-262.

Usefulness of the Visual Cognitive Assessment Test in Detecting Mild Cognitive Impairment in the Community

BACKGROUND

A delay in the detection of mild cognitive impairment (MCI) in the community delays the opportunity for early intervention. Accurate tools to detect MCI in the community are lacking. The Visual Cognitive Assessment Test (VCAT) is a visual based cognitive test useful for multilingual populations without the need for translation.

OBJECTIVE

Here, we evaluate the usefulness of VCAT in detecting MCI in a community population in Singapore.

METHODS

We recruited 301 participants from the community who completed a detailed neuropsychological assessment and 170 of them completed a 3T magnetic resonance imaging (MRI) brain scan. We performed a receiver operating characteristics analysis to test the diagnostic performance of VCAT compared to Montreal Cognitive Assessment (MoCA) in distinguishing MCI from cognitively normal (CN) by measuring area under the curve (AUC). To test for the association of VCAT with structural MRI, we performed a Pearson's correlation analysis for VCAT and MRI variables.

RESULTS

We recruited 39 CN and 262 MCI participants from Dementia Research Centre (Singapore). Mean age of the cohort was 63.64, SD = 9.38, mean education years was 13.59, SD = 3.70 and majority were women (55.8%). VCAT was effective in detecting MCI from CN with an AUC of 0.794 (95% CI 0.723-0.865) which was slightly higher than MoCA 0.699 (95% CI 0.621-0.777). Among subjects with MCI, VCAT was associated with medial temporal lobe atrophy (ρ = -0.265, p = 0.001).

CONCLUSIONS

The VCAT is useful in detecting MCI in the community in Singapore and may be an effective measure of neurodegeneration.

Association between vision and cognitive function among community-dwelling older adults in Selangor, Malaysia

AIM

To determine the association between distance and near visual acuity (VA) and cognitive function among older adults in Selangor, Malaysia.

METHODS

A total of 230 older adults (age ≥60y) participated in this study. Habitual distance and near VA were measured using the Early Treatment Diabetic Retinopathy Study Chart and Lighthouse Near Visual Acuity Chart, respectively. Global cognitive function was assessed using the Mini-Mental State Examination (M-MSE) and the Malay language version of the Montreal Cognitive Assessment (M-MoCA). Digit Symbol (DS) subtest was used to measure information processing.

RESULTS

No significant association was observed between vision and M-MSE and M-MoCA scores. However, poor distance and near VA were found to be significantly associated with low DS scores [distance VA: β=-0.01, R ²=0.1, P=0.02; odds ratio (OR)=2.84, 95% confidence interval (CI), 1.10-7.33, P=0.03; near VA: β=-0.05, R ²=0.08, P=0.00; OR=3.32, 95%CI, 1.28-8.59, P=0.01].

CONCLUSION

Poor vision is associated with a decline in information processing in older adults and substantiates the importance of preserving good vision in maintaining cognitive function.

Current Evidence on the Association of Micronutrient Malnutrition with Mild Cognitive Impairment, Frailty, and Cognitive Frailty among Older Adults: A Scoping Review

Micronutrient malnutrition is thought to play an important role in the cause of cognitive impairment and physical frailty. The purpose of this scoping review was to map current evidence on the association between micronutrient deficiency in blood and mild cognitive impairment, frailty, and cognitive frailty among older adults. The scoping review was conducted based on the 2005 methodological framework by Arksey and O'Malley. The search strategy for potential literature on micronutrient concentration in blood and cognitive frailty was retrieved based on the keywords using electronic databases (PubMed, Cochrane Library, Google Scholar, Ovid, and Science Direct) from January 2010 to December 2021. Gray literature was also included in the searches. A total of 4310 articles were retrieved and 43 articles were incorporated in the review. Findings revealed a trend of significant association between low levels of B vitamins (folate and vitamin B12), vitamin D, vitamin A, vitamin E, omega 3 fatty acid, and albumin, and high homocysteine levels in blood with an increased risk of mild cognitive impairment among older adults. The results also indicated that low vitamin D levels, albumin, and antioxidants (lutein and zeaxanthin) in blood were significantly associated with frailty among older adults, while β-cryptoxanthin and zeaxanthin in blood were inversely associated with the risk of cognitive frailty. Vitamin D and antioxidants seemed to be targeted nutrients for the prevention of cognitive frailty. In conclusion, a wide range of micronutrient deficiency was associated with either mild cognitive impairment or frailty; however, little evidence exists on the dual impairment, i.e., cognitive frailty. This scoping review can serve as preliminary evidence for the association between micronutrient deficiency in blood and mild cognitive impairment, frailty, and cognitive frailty among older adults and prove the relevancy of the topic for future systematic reviews.

Risk scores of incident mild cognitive impairment in a Beijing community-based older cohort

Objective: It is very important to identify individuals who are at greatest risk for mild cognitive impairment (MCI) to potentially mitigate or minimize risk factors early in its course. We created a practical MCI risk scoring system and provided individualized estimates of MCI risk.

Methods: Using data from 9,000 older adults recruited for the Beijing Ageing Brain Rejuvenation Initiative, we investigated the association of the baseline demographic, medical history, lifestyle and cognitive data with MCI status based on logistic modeling and established risk score (RS) models 1 and 2 for MCI. We evaluated model performance by computing the area under the receiver operating characteristic (ROC) curve (AUC). Finally, RS model 3 was further confirmed and improved based on longitudinal outcome data from the progression of MCI in a sub-cohort who had an average 3-year follow-up.

Results: A total of 1,174 subjects (19.8%) were diagnosed with MCI at baseline, and 72 (7.8%) of 849 developed MCI in the follow-up. The AUC values of RS models 1 and 2 were between 0.64 and 0.70 based on baseline age, education, cerebrovascular disease, intelligence and physical activities. Adding baseline memory and language performance, the AUC of RS model 3 more accurately predicted MCI conversion (AUC = 0.785).

Conclusion: A combination of risk factors is predictive of the likelihood of MCI. Identifying the RSs may be useful to clinicians as they evaluate their patients and to researchers as they design trials to study possible early non-pharmaceutical interventions to reduce the risk of MCI and dementia.

The association between global cognitive function and walking capacity in individuals with broad ranges of cognitive and physical function: Are there sex differences?

Introduction

Cognitive function is known to be associated with physical function, where greater walking capacity has been shown to have moderate to strong correlations with global cognitive function and other various domains of cognition in older adults with and without chronic conditions. Biological sex may moderate the relationship between cognitive and physical function, but whether sex differences exist in this association has not been examined in an aging population. The purpose of this study was to examine the associations between global cognitive function (Montreal Cognitive Assessment; MoCA), walking capacity (6-Minute Walk Test distance; 6 MWT) and sex in an aging population with broad ranges of cognitive and physical function.

Methods

Participants were assessed for global cognitive function (MoCA) and walking capacity (6 MWT). Multivariable regression analyses were performed to examine the interaction of sex in the association between MoCA and 6 MWT. First, we presented the unadjusted model (Model 1), then the model adjusted for age, history of stroke, and height (Model 2). To determine if there were sex-based differences in the association between global cognitive function and walking capacity, we included sex and an interaction term between sex*6 MWT distance in Models 3 and 4.

Results

Twenty-three females and 36 males were included in the multivariable regression analyses, respectively. Our sample represented broad ranges of cognitive and physical function levels, where MoCA scores ranged from 13 to 30, and 6 MWT distances from 203 to 750 m. 6 MWT distance was associated with MoCA in models unadjusted (R2 = 0.17; F(1,56) = 11.4; p &lt; 0.01) and adjusted for age, stroke history, and height (R2 = 0.20; F(4,53) = 3.2; p = 0.02). No interaction with sex was found, but a main effect of sex was observed (R2 = 0.26; F(5,21) = 3.72; p = 0.03). When adjusting for age, height and history of stroke, males MoCA scores were 2.9 ± 1.3 less than the mean MoCA scores for females.

Discussion

Our findings confirm the positive relationship between cognitive and physical function in older adults. Notably, we also observed superior performance in global cognition among females that was consistent across a broad spectrum of walking capacity.

Oxidative stress and antioxidant defenses in mild cognitive impairment: A systematic review and meta-analysis

This study aims to systematically review and meta-analyze the nitro-oxidative stress (O&NS)/antioxidant (ANTIOX) ratio in the peripheral blood of people with mild cognitive impairment (MCI). We searched PubMed, Scopus, Google Scholar, and Web of Science for articles published from inception until July 31, 2021. Forty-six studies on 3.798 MCI individuals and 6.063 healthy controls were included. The O&NS/ANTIOX ratio was significantly higher in MCI than in controls with a Standardized Mean Difference (SMD)= 0.378 (95% CI: 0.250; 0.506). MCI individuals showed increased lipid peroxidation (SMD=0.774, 95%CI: 4.416; 1.132) and O&NS-associated toxicity (SMD=0.621, CI: 0.377; 0.865) and reduced glutathione (GSH) defenses (SMD=0.725, 95%CI: 0.269; 1.182) as compared with controls. MCI was also accompanied by significantly increased homocysteine (SMD=0.320, CI: 0.059; 0.581), but not protein oxidation, and lowered non-vitamin (SMD=0.347, CI: 0.168; 0.527) and vitamin (SMD=0.564, CI: 0.129; 0.999) antioxidant defenses. The results show that MCI is at least in part due to increased neuro-oxidative toxicity and suggest that treatments targeting lipid peroxidation and the GSH system may be used to treat or prevent MCI.

Demographic and Clinical Profile of Patients with Mild Cognitive Impairment Seen at St. Luke's Medical Center-Global City Memory Service

INTRODUCTION

Mild cognitive impairment (MCI) is a dynamic state, which has evolved into a highly defined condition due to its association with dementia syndromes. There are no published data on the demographic and clinical characteristics of MCI in the Philippines. These data will help in defining the population at risk for the condition and in modifying the factors for its prevention.

METHODS

From 2010 to 2019, 434 subjects were diagnosed with MCI based on the criteria published by the International Working Group on MCI last 2004. The demographic profile, vascular risk factors, and levels of Vitamin B12, Vitamin D, and homocysteine were reviewed. Results of neuropsychological tests, such as Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog), Mini-Mental State Exam (MMSE), and Montreal Cognitive Assessment (MoCA), were collected. The Fazekas score of the cranial magnetic resonance imaging of patients was also considered.

RESULTS

The median age was 72 years [34-97] with 58.3% females. The median years of education were 14 [4-28]. Median ADAS-Cog, MMSE, and MoCA scores were 11.3 [0-27.67], 27 [13-30], and 21 [7-30], respectively. Hypertension and dyslipidemia were present in 66.8% and 64.1%, respectively. Normal homocysteine, Vitamin B12, and Vitamin D levels were found in 64.2%, 59.8%, and 48.8%, respectively. The median Fazekas score was 1 (59.4%).

CONCLUSION

This is the first study to document the demographic and clinical profile of Filipinos with MCI in a clinical setting. This review serves as a foundation for increased understanding of MCI with the ultimate goal of controlling the factors which may impact its prevention.

Chinese herbal medicine for mild cognitive impairment using mini-mental state examination: A systematic review and meta-analysis

INTRODUCTION

The prevalence of mild cognitive impairment (MCI) in the elderly population aged 60 to 84 years ranges from 6.7% to 25.2%, and the effective prevention and reversal of MCI progression to Alzheimer disease (AD) is crucial. The mini mental state examination (MMSE) is the most commonly used screening tool in Chinese outpatient clinics, with sufficient sensitivity and specificity to allow useful stratification from average to abnormal with adequate consideration of age and education.

OBJECTIVE

To investigate the clinical significance of Chinese herbs on MMSE scores in MCI patients and discuss the effectiveness of Chinese herbs through pharmacology.

METHODS

Three English databases and 4 Chinese databases we have searched, and the risk of bias was assessed according to the Cochrane tool. Statistics will be used for heterogeneity assessment, sensitivity analysis, data synthesis, funnel plot generation and subgroup analysis. If sufficiently homogeneous studies are found, a Meta-analysis will be performed, with subgroups describing any differences.

RESULTS

A total of 21 studies were included, 4 studies were placebo-controlled, 14 Chinese Herbal Medicines (CHMs) were compared with other cognitive improvements, 3 CHMs were combined with other medications, and the results of 17 studies favored the herbal group.

CONCLUSION

The results indicate that herbal medicine can improve MMSE scores, and herbal medicine combined with other drugs that can improve cognition can significantly improve MMSE scores, but there are methodological flaws in the study. Experimental studies have found a basis for the ability of herbs to improve cognition and memory impairment, and herbal medicine has great potential to improve MCI cognition. Keywords mild cognitive impairment, herbal medicine, MMSE, systematic evaluation, meta-analysis. PROSPERO international prospective register of systematic reviews protocol registration number: CRD42020202368.

Multiparametric MRI for the improved diagnostic accuracy of Alzheimer's disease and mild cognitive impairment: Research protocol of a case-control study design

Background

Alzheimer’s disease (AD) is a major neurocognitive disorder identified by memory loss and a significant cognitive decline based on previous level of performance in one or more cognitive domains that interferes in the independence of everyday activities. The accuracy of imaging helps to identify the neuropathological features that differentiate AD from its common precursor, mild cognitive impairment (MCI). Identification of early signs will aid in risk stratification of disease and ensures proper management is instituted to reduce the morbidity and mortality associated with AD. Magnetic resonance imaging (MRI) using structural MRI (sMRI), functional MRI (fMRI), diffusion tensor imaging (DTI), and magnetic resonance spectroscopy (¹H-MRS) performed alone is inadequate. Thus, the combination of multiparametric MRI is proposed to increase the accuracy of diagnosing MCI and AD when compared to elderly healthy controls.

Methods

This protocol describes a non-interventional case control study. The AD and MCI patients and the healthy elderly controls will undergo multi-parametric MRI. The protocol consists of sMRI, fMRI, DTI, and single-voxel proton MRS sequences. An eco-planar imaging (EPI) will be used to perform resting-state fMRI sequence. The structural images will be analysed using Computational Anatomy Toolbox-12, functional images will be analysed using Statistical Parametric Mapping-12, DPABI (Data Processing & Analysis for Brain Imaging), and Conn software, while DTI and ¹H-MRS will be analysed using the FSL (FMRIB’s Software Library) and Tarquin respectively. Correlation of the MRI results and the data acquired from the APOE genotyping, neuropsychological evaluations (i.e. Montreal Cognitive Assessment [MoCA], and Mini–Mental State Examination [MMSE] scores) will be performed. The imaging results will also be correlated with the sociodemographic factors. The diagnosis of AD and MCI will be standardized and based on the DSM-5 criteria and the neuropsychological scores.

Discussion

The combination of sMRI, fMRI, DTI, and MRS sequences can provide information on the anatomical and functional changes in the brain such as regional grey matter volume atrophy, impaired functional connectivity among brain regions, and decreased metabolite levels specifically at the posterior cingulate cortex/precuneus. The combination of multiparametric MRI sequences can be used to stratify the management of MCI and AD patients. Accurate imaging can decide on the frequency of follow-up at memory clinics and select classifiers for machine learning that may aid in the disease identification and prognostication. Reliable and consistent quantification, using standardised protocols, are crucial to establish an optimal diagnostic capability in the early detection of Alzheimer’s disease.

Randomized Controlled Trials of a Psychosocial Intervention for Improving the Cognitive Function among Older Adults: A Scoping Review

Aim: The goal is to explore available evidence and provide greater clarity to what is described as psychosocial intervention to improve cognitive function among older population with MCI as well as identifying areas for future research. Methods: An electronic literature search of PubMed, Cochrane, Ebscohost, Medline, Scopus, and gray resource was conducted to find articles published in English language between 2010 and September 2020. This review focused on research undertaken using randomized clinical trials study design. We extracted information regarding the publication date, geographical location, study setting, intervention mechanism, type of cognitive measurement used, and outcome of the studies. References of this literature were also reviewed to ensure comprehensive search. Result: Out of 240 potential records found, a total of 27 articles were identified following the first round of screening and deletion of duplicates. Full-text article reviews and analysis in the second round of screening narrowed the selection down to four articles. Another three relevant articles obtained from references were also included making a total of seven articles in the final analysis. Findings: Psychosocial intervention strategies for improvement of cognitive function, done in various setting all over the globe, covered a range of approaches including art therapy, visual art therapy, therapeutic writing therapy, reminiscence activity, and cognitive behavioral approach. Most were conducted in weekly basis within 1-to-2-hour duration of session. Cognitive function of older adult in psychosocial intervention group was significantly improved in two studies. Three studies showed no significant improvement at all in the cognitive function, and another one reported success in improving cognitive function over time in the intervention group than in control group. One study did not describe the interaction effect. Different types of cognitive measurement also were used to quantify different domains of cognitive function in the reviewed studies. Conclusion: The idea of using psychosocial intervention for improving cognitive function has begun to increasingly accepted recently. Findings from the limited studies are encouraging, although the outcome of the cognitive function was mixed. Large-scale and longer duration of psychosocial intervention with bigger sample size is warranted for future studies.

The Humanoid Robot Sil-Bot in a Cognitive Training Program for Community-Dwelling Elderly People with Mild Cognitive Impairment during the COVID-19 Pandemic: A Randomized Controlled Trial

Background: Mild cognitive impairment (MCI) is a stage preceding dementia, and early intervention is critical. This study investigated whether multi-domain cognitive training programs, especially robot-assisted training, conducted 12 times, twice a week for 6 weeks can improve cognitive function and depression decline in community-dwelling older adults with mild cognitive impairment (MCI). Methods: A randomized controlled trial was conducted with 135 volunteers without cognitive impairment aged 60 years old or older. Participants were first randomized into two groups. One group consisted of 90 participants who would receive cognitive training and 45 who would not receive any training (NI). The cognitive training group was randomly divided into two groups, 45 who received traditional cognitive training (TCT) and 45 who received robot-assisted cognitive training (RACT). The training for both groups consisted of a daily 60 min session, twice a week for six weeks. Results: RACT participants had significantly greater post-intervention improvement in cognitive function (t = 4.707, p < 0.001), memory (t = −2.282, p = 0.007), executive function (t = 4.610, p < 0.001), and depression (t = −3.307, p = 0.004). TCT participants had greater post-intervention improvement in memory (t = −6.671, p < 0.001) and executive function (t = 5.393, p < 0.001). Conclusions: A 6-week robot-assisted, multi-domain cognitive training program can improve the efficiency of global cognitive function and depression during cognitive tasks in older adults with MCI, which is associated with improvements in memory and executive function.

Comparison of Subjective and Objective Methods to Measure the Physical Activity of Non-Depressed Middle-Aged Healthy Subjects with Normal Cognitive Function and Mild Cognitive Impairment-A Cross-Sectional Study

This study compared subjective and objective methods of measuring different categories of physical activity in non-depressed middle-aged subjects with normal cognitive function (NCF) and mild cognitive impairment (MCI). In total, 75 participants (NCF: n = 48, MCI: n = 27) were recruited and physical activity was assessed for seven days using the ActiGraph and the International Physical Activity Questionnaire (IPAQ). Anthropometric parameters, body compositions, resting metabolic rate, and energy expenditure were also assessed. ActiGraph data indicated that subjects with NCF were more active than MCI subjects. A comparison of the IPAQ and the ActiGraph data revealed a significant correlation between these methods for total (r = 0.3315, p < 0.01) and moderate (r = 0.3896, p < 0.01) physical activity in the total population and moderate activity (r = 0.2893, p < 0.05) within the NCF group. No associations between these methods were found within the MCI group. Independent predictors of subjectively evaluated total physical activity were alcohol consumption (p = 0.0358) and socio-professional status (p = 0.0288), while weight (p = 0.0285) and the Montreal Cognitive Assessment results (p = 0.0309) were independent predictors of objectively measured physical activity. In conclusion, the long version of IPAQ is a more reliable tool to assess PA in subjects with NCF than those with MCI. More studies are needed to confirm this finding.

Effects of Aerobic and Resistance Exercise Interventions on Cognitive and Physiologic Adaptations for Older Adults with Mild Cognitive Impairment: A Systematic Review and Meta-Analysis of Randomized Control Trials

(1) Background: The purpose of this meta-analysis is to investigate the effects of exercise intervention for older adults with mild cognitive impairment (MCI). (2) Methods: Databases including PubMed, Medline, and Cochrane were used to search for studies that reported effects of exercise for older adults with MCI and randomized controlled trials up to July 2020. Exercise interventions of all selected studies were summarized, and effect sizes of exercise interventions were calculated. (3) Results: A total of 14 studies, including 1178 older adults with MCI were included. Exercise participation in older adults with MCI improved cognitive functions (d = 0.88, 95% confidence interval [CI]; 0.10-1.65, p = 0.01; k = 5]) and handgrip strength (d = 0.62, 95% [CI]; 0.23-1.01, p = 0.00; k = 4) compared with control groups. Aerobic exercise or resistance exercise at moderate to vigorous levels for at least 150 min, 1 time/week, for 6 weeks was the minimum level to obtain beneficial effects from exercise for older adults with MCI. (4) Conclusions: Older adults with MCI who participated in exercise received beneficial effects, including improvement in cognitive functions and handgrip strength, but further studies to confirm the effects are needed.

Prevalence and incidence of cognitive impairment in an elder Portuguese population (65-85 years old)

BACKGROUND

The increase in average life expectancy increases the risk of illness and frailty in the elderly, especially in the cognitive arena. This study has the objective to estimate the prevalence and incidence of cognitive impairment, in a representative sample of 65 to 85 years old followed for a mean period of 6-years.

METHODS

Subjects aged 65-85 years (n = 586) were screened at baseline (1999-2004) to estimate the prevalence of cognitive impairment using the Mini-Mental State Examination. A total of 287 individuals with a normal MMSE at baseline were reassessed after 6.2 mean years (± 4.30 years) to evaluate the incidence of cognitive impairment, defined as scoring below the age and education-adjusted MMSE cut-off points adapted for the Portuguese population. We did not exclude Dementia.

RESULTS

The baseline prevalence of cognitive impairment was 15.5% (95% CI: 12.7-18.7). Higher in women (18.9%; 95% CI: 14.9-23.3), that in men (10.4%; 95% CI: 6.7-15.1). Increased with age and was highest for participants without any schooling. The overall incidence rate was 26.97 per 1000 person-years; higher in women (33.8 per 1000 person-years) than in men (18.0 per 1000 person-years). Higher for the oldest participants and those with no schooling. Taking the standard European population, we estimated a prevalence of 16.5% and an incidence of 34.4 per 1000 person-years.

CONCLUSION

The prevalence of cognitive impairment in Portugal is within the estimated interval for the European population, and the incidence is lower than for the majority of the European countries. Women, senior and elders without education have a higher risk of cognitive impairment. In our sample, neither employment nor marital status has a significant effect on cognitive impairment.

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.

Rahman MH, Mohammed Z, You YX. Incidence and Predictors of Cognitive Frailty Among Older Adults: A Community-based Longitudinal Study

(1) Background: Cognitive frailty (CF) is the simultaneous presence of physical frailty and cognitive impairment with an increased risk of dementia. Considering that the risk factors of CF are mostly elucidated from cross-sectional studies, we conducted a community-based longitudinal study to determine the incidence and the predictors of CF among Malaysian older adults.; (2) Methods: Out of 490 older adults participating in the Malaysian Towards Useful Aging (TUA) study, 282 were successfully followed-up at five-years for an analysis of the CF incidence. CF was defined as a comorbid physical frailty (>1 Fried criteria) and mild cognitive impairment (Petersen criteria). A comprehensive interview-based questionnaire was administered for sociodemographic information, cognitive function, physical function, dietary intake, psychosocial, and biochemical indices. Univariate analyses were performed for each variable, followed by a regression analysis to identify the predictors of CF that accounted for confounding effects between the studied factors; (3) Results: The incidence rate of CF was 7.1 per 100 person-years. Advancing age (OR=1.12, 95% CI:1.04-1.21, p < 0.05), depression (OR=1.20, 95% CI:1.05-1.37, p < 0.05), decreased processing speed, assessed by a lower digit symbol score (OR=0.67, 95%CI:0.0.56-0.80, p < 0.05), decreased functional mobility measured using Timed-Up-and-Go (TUG) (OR=1.23, 95% CI:1.04-1.46, p < 0.05), low vitamin D intake (OR:0.36, 95% CI:0.14-0.93, p < 0.05) and physical frailty (OR=2.16, 95% CI:1.02-4.58, p < 0.05) were predictors for CF incidence; and (4) Conclusions: Our study results could be used as an initial reference for future studies to formulate effective preventive management and intervention strategies to decelerate CF development among older adults.