Recent research about mild cognitive impairment in China

Prevalence of cognitive impairment and metabolic syndrome among older adults in calabar metropolis and the associated risk factors

BACKGROUND

The number of people reaching old age is rising, bringing an increase in age-related diseases like cardiovascular conditions and cognitive dysfunction. Cognitive impairment (CI) impacts various brain functions, affecting daily activities and quality of life. Metabolic syndrome (MetS), a cluster of cardiovascular risk factors, has been implicated in CI. This study examines the prevalence of MetS and CI among older adults in Calabar Metropolis and the associated risk factors.

METHODS

This study was conducted in Calabar Metropolis, Cross River State, Nigeria, with 236 older adults (aged 65 years and above) selected via a multi-stage sampling technique. Informed consent was obtained from all participants. Physical examinations and biomarker assessments included measurements of blood pressure, height, weight, waist and hip circumference, fasting plasma glucose, cholesterol, triglycerides, and high-density lipoprotein (HDL) levels. MetS was defined according to the NCEP Adult Treatment Panel III criteria. CI was assessed using the Mini-Cog™ test, with scores ≤ 3 indicating poor cognitive status. Data analysis utilized SPSS version 26.0, employing chi-square tests and binary logistic regression. Significance was set at p < 0.05.

RESULTS

The prevalence of MetS was 32.2%, and CI was observed in 44% of participants. Females had a slightly higher prevalence (57.9%) of MetS compared to males (42.1%). Significant differences were found between MetS and non-MetS groups in systolic blood pressure, fasting blood sugar, triglycerides, abdominal obesity, and cardiovascular risk. MetS overall was not significantly associated with CI. However, reduced HDL levels were significantly linked to poor cognitive status (OR = 70.528, 95% CI = 3.269-1521.748). Other MetS components did not show significant associations with CI.

CONCLUSIONS

This study highlights the prevalence of MetS and CI among older adults in Calabar Metropolis. The findings suggest that while MetS as a whole is not associated with CI, reduced HDL levels are significantly linked to poor cognitive status. The findings emphasize the importance of managing specific metabolic risk factors, particularly HDL, to maintain cognitive health in elderly population.

CLINICAL TRIAL REGISTRATION

Not applicable.

Influence and interaction of resting state functional magnetic resonance and tryptophan hydroxylase-2 methylation on short-term antidepressant drug response

BACKGROUND

Most antidepressants have been developed on the basis of the monoamine deficiency hypothesis of depression, in which neuronal serotonin (5-HT) plays a key role. 5-HT biosynthesis is regulated by the rate-limiting enzyme tryptophan hydroxylase-2 (TPH2). TPH2 methylation is correlated with antidepressant effects. Resting-state functional MRI (rs-fMRI) is applied for detecting abnormal brain functional activity in patients with different antidepressant effects. We will investigate the effect of the interaction between rs-fMRI and TPH2 DNA methylation on the early antidepressant effects.

METHODS

A total of 300 patients with major depressive disorder (MDD) and 100 healthy controls (HCs) were enrolled, of which 60 patients with MDD were subjected to rs-fMRI. Antidepressant responses was assessed by a 50% reduction in 17-item Hamilton Rating Scale for Depression (HAMD-17) scores at baseline and after two weeks of medication. The RESTPlus software in MATLAB was used to analyze the rs-fMRI data. The amplitude of low-frequency fluctuation (ALFF), regional homogeneity (ReHo), fractional ALFF (fALFF), and functional connectivity (FC) were used, and the above results were used as regions of interest (ROIs) to extract the average value of brain ROIs regions in the RESTPlus software. Generalized linear model analysis was performed to analyze the association between abnormal activity found in rs-fMRI and the effect of TPH2 DNA methylation on antidepressant responses.

RESULTS

Two hundred ninety-one patients with MDD and 100 HCs were included in the methylation statistical analysis, of which 57 patients were included in the further rs-fMRI analysis (3 patients were excluded due to excessive head movement). 57 patients were divided into the responder group (n = 36) and the non-responder group (n = 21). Rs-fMRI results showed that the ALFF of the left inferior frontal gyrus (IFG) was significantly different between the two groups. The results showed that TPH2-1-43 methylation interacted with ALFF of left IFG to affect the antidepressant responses (p = 0.041, false discovery rate (FDR) corrected p = 0.149).

CONCLUSIONS

Our study demonstrated that the differences in the ALFF of left IFG between the two groups and its association with TPH2 methylation affect short-term antidepressant drug responses.

Associations between pulmonary function and cognitive decline in the middle-aged and older adults: evidence from the China Health and Retirement Longitudinal Study

BACKGROUND

Studies observing the relationship between pulmonary function and the risk of cognitive impairment in middle-aged and older adults was increasing, but the results were inconsistent. To date, evidence from longitudinal data is scarce and further research is urgently needed.

METHODS

We used data from the China Health and Retirement Longitudinal Study. Participants were enrolled in 2011/2013 and followed up in 2013, 2015 and 2018. Pulmonary function was assessed via peak expiratory flow (PEF). Cognitive function, measured by episodic memory and mental status, was assessed through a face-to-face interview in each survey.

RESULTS

A total of 8,274 participants (52.86% males; mean age, 56.44 years) were included. The scores of global cognition (12.46 versus 11.51, P < 0.001) of men were significantly higher than women at baseline, with a total of 5096 participants (61.59%) declining during the follow-up. Higher baseline PEF was associated with lower absolute decline in global cognition (OR per 1-SD difference 0.921; P = 0.031) and mental status (OR per 1-SD difference 0.9889; P = 0.002) during follow-up in men, and significant associations between higher baseline PEF and a lower absolute decline in the episodic memory were both found in men (OR per 1-SD difference 0.907; P = 0.006) and women (OR per 1-SD difference 0.915; P = 0.022). Second analysis showed that the significant associations between positive PEF variation and a lower rate of 4-year decline in global cognition, mental status and episodic memory were all only found in men. In subgroup analyses, higher PEF at baseline was significantly associated with a lower absolute decline of global cognition among male individuals >60 years. Significant associations between higher PEF at baseline and lower absolute decline in global cognition and episodic memory during follow-up were only found in never-smokers, while higher PEF was related to lower absolute decline in mental status among non-smoking and smoking males.

CONCLUSIONS

Pulmonary function correlates with cognitive functions in middle-aged and older people, especially males. Additional studies characterizing early and long-term PEF changes are needed.

Mild cognitive impairment: when nutrition helps brain energy rescue-a report from the EuGMS 2020 Congress

BACKGROUND

Mild cognitive impairment (MCI) is characterized by a decline in cognition and mainly affects older individuals above the age of 60. The global incidence of MCI varies, but it is often underdiagnosed and untreated. There is a distinct lack of approved pharmacologic options to treat MCI. There is, however, evidence to support the efficacy of nutritional interventions, such as ketogenic supplements/diets, which offer ketones as an alternative energy source to brain cells. This article explores the effect of ketones on metabolic activity in the brain and the mechanisms by which ketogenic medium-chain triglycerides (kMCTs) induce ketosis in patients with MCI.

KEY TAKEAWAYS

This article reviews the effect of ketogenic supplements/diets on brain metabolism, including evidence supporting the efficacy of ketones as an efficient fuel for the brain. It discusses the use of oral nutritional ketogenic supplements, with particular reference to the 6-month randomized controlled BENEFIC trial, which showed that consumption of a kMCT drink, BrainXpert Energy Complex, improved cognitive performance in individuals with MCI compared with placebo.

CONCLUSION

While there is a need for more long-term studies, results from the BENEFIC trial revealed the benefits of a brain-specific ketogenic supplement, as a nutritional intervention, on cognitive performance in individuals with MCI.

The association of metabolic syndrome and cognitive impairment in Jidong of China: a cross-sectional study

BACKGROUND

Metabolic syndrome (Mets) is prevalent in the general population and has been reported to be an independent risk factor for cognitive impairment. This study aimed to investigate the association of Mets with the risk of cognitive impairment.

METHODS

We studied 5854 participants from the Jidong community. Cognitive function was assessed by the Mini-Mental State of Examination (MMSE) scale. Mets was diagnosed according to the International Diabetes Federation criteria. We used logistic regression analysis to investigate the association of metabolic syndrome with the risk of cognitive impairment.

RESULT

Among the 5854 adults included in the study, the age mean (SD) of age was 44 (13.57) years, and 2916 (50.34%) were male. There was a higher (56.03%) cognitive impairment incidence rate among participants with Mets than among those without Mets. In addition, there was a significant association between Mets and cognitive impairment (OR: 2.39, 95% CI: 2.00-2.86, P < 0.05) after adjusting for potential confounders, including age, gender, education level, marital status, smoking and alcohol consumption status. Regarding the 5 Mets components, abdominal obesity and elevated blood pressure were associated with the risk of Mets (OR: 1.36, 95% CI: 1.09-1.70, P < 0.001; OR: 1.32, 95% CI: 1.07-1.63, P < 0.05). Moreover, the strongest statistical correlation (adjusted OR: 1.86, 95% CI: 1.22-2.83, P < 0.05) was found when the number of Mets components was three.

CONCLUSION

Our study suggested that Mets was associated with cognitive impairment and that abdominal obesity and hypertension were associated with an increased risk of 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.

Effects of different acupuncture treatment methods on mild cognitive impairment: a study protocol for a randomized controlled trial

BACKGROUND

Mild cognitive impairment (MCI) is an intermediate state between normal aging and Alzheimer's disease, which is the world's most common form of dementia. It is important to identify early and easily available interventions to delay the progression of MCI to Alzheimer's disease. Acupuncture has been reported to improve the clinical outcomes of MCI treatment. Acupuncture is a complex intervention, involving both specific and non-specific factors associated with therapeutic benefits. Therefore, we intend to obtain basic data for developing an optimal acupuncture treatment for MCI by comparing the effects of different acupuncture treatment methods on cognitive function in MCI patients.

METHODS

This study will be a prospective, outcome-assessor-blinded, parallel-arm, single-center (DongShin University Gwangju Korean Medicine Hospital, Republic of Korea), randomized controlled clinical trial. Thirty-two participants with MCI will be randomized in equal numbers to four groups (basic acupuncture (BA), acupoint specificity (AS), needle duration (ND), or electroacupuncture (EA)) and receive acupuncture treatment once per day, 3 days/week for 8 weeks. The BA and ND groups will receive acupuncture treatment for 30 and 20 min, respectively, at Baihui (GV20), Sishencong (EX-HN1), Fengchi (GB20), and Shenting (GV24). The EA group will receive electroacupuncture treatment at the same acupoints for 30 min. The AS group will receive acupuncture treatment at GV20, EX-HN1, GB20, GV24, and Taixi (KI3) for 30 min. The outcome measured will be scores on the Korean version of the Alzheimer's Disease Assessment Scale-cognitive subscale, the Korean version of the Montreal Cognitive Assessment, the Center for Epidemiological Studies Depression scale, the Korean Activities of Daily Living scale, the Korean Instrumental Activities of Daily Living scale, and the European Quality of Life Five Dimension Five Level scale. All scores will be recorded before intervention, 8 weeks after the first intervention, and 12 weeks after completing the intervention.

DISCUSSION

Four acupuncture protocols will be assessed and compared as potential MCI treatments. This study is expected to provide data to be used in developing an optimal acupuncture method for MCI treatment.

TRIAL REGISTRATION

Clinical Research Information Service, KCT0003430 . Registered on 16 January 2019. http://cris.nih.go.kr ).

Effects of electroacupuncture combined with computer-based cognitive rehabilitation on mild cognitive impairment: study protocol for a pilot randomized controlled trial

BACKGROUND

Mild cognitive impairment (MCI) is defined as an intermediate stage between normal aging and Alzheimer's disease (AD), and early and easily available interventions to delay the progress of MCI to AD are necessary. Feasible complementary and alternative therapies such as electroacupuncture (EA), exercise, and cognitive training have shown some beneficial effects on MCI and AD. Here we report the protocol for a randomized controlled trial of the efficacy and safety of EA combined with computer-based cognitive rehabilitation (EA-CCR) for the treatment of MCI.

METHODS

The study will be a prospective, outcome assessor-blinded, parallel-arm, single-center (DongShin University Gwangju Korean Medicine Hospital, Republic of Korea), pilot randomized controlled clinical trial with a 1:1 allocation ratio. Participants with MCI will be randomized to a computer-based cognitive rehabilitation (CCR) or an EA-CCR group (n = 18 each). The CCR group will receive RehaCom cognitive rehabilitation once (30 min) a day, 3 days per week (excluding Saturday and Sunday) for 8 weeks. The EA-CCR group will receive EA at Baihui (GV20), Sishencong (EX-HN1), Fengchi (GB20), and Shenting (GV24) in addition to RehaCom cognitive rehabilitation once (EA:30 min, CCR:30 min) a day, 3 days per week (excluding Saturday and Sunday) for 8 weeks. The primary outcome will be an improvement in cognitive function assessed using the Korean version of the Alzheimer's Disease Assessment Scale-cognitive subscale. Scores for the Korean version of the Montreal Cognitive Assessment scale, Center for Epidemiological Studies Depression Scale, Korean Activities of Daily Living scale, Korean Instrumental Activities of Daily Living scale, and European Quality of Life Five Dimension Five Level Scale will be recorded as secondary outcome measures. All scores will be recorded at baseline (before intervention), 8 weeks after the first intervention (i.e., at the end of the intervention), and 12 weeks after completion of the intervention.

DISCUSSION

The study is expected to provide preliminary evidence regarding the efficacy, safety, and usefulness of EA-CCR for the treatment of MCI.

TRIAL REGISTRATION

Korea Clinical Information Service, cris.nih.go.kr, KCT0003415 . Registered on 4 January 2019. Retrospectively registered, http://cris.nih.go.kr .

Prevalence, Influence Factors and Cognitive Characteristics of Mild Cognitive Impairment in Type 2 Diabetes Mellitus

Background: Type 2 diabetes mellitus (T2DM) is considered as an independent risk factor for mild cognitive impairment (MCI). This study was performed to investigate the prevalence, influencing factors and cognitive characteristics of MCI in elderly patients with T2DM in China.

Methods: In the cross-sectional study, we performed cluster random sampling of 3,246 people age 60 years and older across the country. All participants were interviewed and screened for T2DM and MCI. A total of 341 subjects were diagnosed of MCI according to the criteria of Petersen, and a total of 256 subjects were diagnosed of T2DM by using the American Diabetes Association criteria Among the 256 T2DM people, 56 were also diagnosed with MCI. Logistic regression analyses were performed to evaluate risk and protective factor for MCI with T2DM. We also assessed their cognitive function by using the Mini-mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Digit span, Associative Learning Test (ALT), Visual Identification Test (VIT), Verbal Fluency (VF), Wechsler Adult Intelligence Scale (WAIS)-III Block Design, WAIS-III picture completion and Auditory Verbal Learning Test (AVLT).

Results: Among the 256 T2DM patients, 56 were diagnosed with MCI, and the prevalence of MCI in T2DM was 21.8%. Multivariate logistic regression analyses showed that depression (p = 0.002, OR = 6.220, 95% CI: 2.005–19.290) was a risk factor for MCI among T2DM patients, while education (p < 0.001, OR = 0.869, 95% CI: 0.805–0.983) was a protective one. All the scores of neuropsychological tests (except for MMSE) in T2DM patients with MCI were lower than those without MCI (p < 0.05), but there was no statistical difference (p > 0.05) in neuropsychological tests between T2DM-MCI group and No-T2DM-MCI group. Linear regression analysis showed that the drug treatment of diabetes was positively correlated (t = 2.263, p = 0.025) with the total score of auditory word tests.

Conclusions: The present study suggests a high prevalence of MCI among Chinese T2DM patients. Depression is a risk factor for MCI, while education is a protective one. T2DM patients with MCI often show comprehensive cognitive impairment, and the drug treatment of diabetes might help to improve cognitive function.

Comparative analysis of cognitive impairment prevalence and its etiological subtypes in a rural area of northern China between 2010 and 2015

The purpose of this study was to evaluate changes in the prevalence and risk factors of cognitive impairment (CI) by analyzing and comparing two cross-sectional epidemiological surveys of CI and its subtypes were performed in a rural area of northern China between 2010 and 2015. Residents aged ≥60 years were drawn in northern China. The Mini Mental State Examination (MMSE) is recommended to test for CI. Dementia was further categorised into Alzheimer’s disease (AD), vascular dementia (VaD), and dementia caused by other diseases (ODs). Mild cognitive impairment (MCI) was classified into MCI caused by AD (MCI-A), MCI caused by VaD (MCI-VD), and MCI caused by ODs (MCI-O). The prevalence of CI increased in China. The prevalence of all-cause CI was 30·5% (22.9% MCI and 7.6% dementia) in 2010. The prevalence of all-cause CI was 38.3% (27.8% MCI and 10.5% dementia) in 2015. Similar increases were observed for the prevalence of subtypes of dementia and MCI. These findings suggest an increasing prevalence of CI and its subtypes in China, which may be related to alterations in sociodemographic factors, vascular risk factors and lifestyle changes over time in these cohorts.

Prevalence and correlates of cognitive impairment and depression among elderly people in the world's fastest growing city, Chongqing, People's Republic of China

Background

Cognitive impairment and depression are major mental health problems affecting older people. The current study was designed to explore the prevalence of cognitive impairment and depression in representative sample of elderly people aged ≥60 years and to examine the correlates of cognitive impairment and depression with other sociodemographic variables.

Methods

A cross-sectional study based on comprehensive geriatric assessment of 538 elderly Chinese people was conducted from September 2011 to August 2012. Cognitive impairment was assessed using the Chinese version of Mini-Mental State Examination, and depressive symptoms were assessed by 30-item geriatric depression scale.

Results

The prevalence of cognitive impairment was 12.6%. Multiple logistic regression analysis revealed that the following were significant independent predictors of cognitive impairment: female, having a low level of education, increasing age, and depression. The overall prevalence of depression was 24.3%, and in adjusted model, cognitive impairment was only associated with increased risk of depression.

Conclusion

Cognitive impairment and depression are prevalent in elderly Chinese people. Among a number of factors identified in our study, cognitive impairment and depression were highly correlated in elderly people aged ≥60 years.

A research agenda for aging in China in the 21st century

China is encountering formidable healthcare challenges brought about by the problem of aging. By 2050, there will be 400 million Chinese citizens aged 65+, 150 million of whom will be 80+. The undesirable consequences of the one-child policy, rural-to-urban migration, and expansion of the population of 'empty nest' elders are eroding the traditional family care of the elders, further exacerbating the burden borne by the current public healthcare system. The challenges of geriatric care demand prompt attention by proposing strategies for improvement in several key areas. Major diseases of the elderly that need more attention include chronic non-communicable diseases and mental health disorders. We suggest the establishment of a home care-dominated geriatric care system, and a proactive role for researchers on aging in reforming geriatric care through policy dialogs. We propose ideas for preparation of the impending aging burden and the creation of a nurturing environment conducive to healthy aging in China.

Population Difference in the Associations of KLOTH Promoter Methylation with Mild Cognitive Impairment in Xinjiang Uygur and Han Populations

Background

Mild cognitive impairment (MCI) is the intermediate stage of the cognitive changes between normal aging and dementia. KLOTH is an age-related gene that may contribute to the risk of MCI. The aim of our study was to explore the association between KLOTHO promoter methylation and MCI in Xinjiang Uygur and Han populations.

Methods

DNA methylation assay was performed using the bisulphite pyrosequencing technology among 96 Uygur (48 MCI and 48 controls) and 96 Han (48 MCI and 48 controls) Chinese individuals from Xinjiang province of China.

Results

We found significant association between KLOTHO promoter methylation and MCI in the Han Chinese (CpG1: p = 3.77E-06; CpG2: p = 1.91E-07; CpG3: p = 5.83E-07; CpG4: p = 2.23E-05; CpG5: p = 3.03E-06) but not in the Uygur Chinese. Higher KLOTHO promoter methylation levels were found in Han MCI patients than Uygur MCI patients for all the five CpGs (adjusted p values by age < 0.02).

Conclusion

Our results showed that KLOTHO promoter hypermethylation contributed to the MCI risk in Xinjiang Han Chinese but not in Xinjiang Uygur Chinese. The population difference of KLOTHO methylation in the risk of MCI required further investigation in the future.