A meta-analysis of the accuracy of the mini-mental state examination in the detection of dementia and mild cognitive impairment

Auditory distraction, time perception, and the role of age: ERP evidence from a large cohort study

Cognitive aging is typically associated with a higher susceptibility to distraction by concurrent, but task-irrelevant stimuli. Here, we studied the cognitive sub-processes involved in a sample of 484 healthy adults aged 20-70 years from the Dortmund Vital Study (Clinicaltrials.gov NCT05155397). Participants judged the duration of tone stimuli of a random sequence of long and short tones, having either a regular (standard) pitch or rare (deviant) pitch. Deviance-related ERPs were explored, reflecting neuro-cognitive correlates of pre-attentive deviance detection (MMN), attention allocation toward (P3a) and processing of (P3b) the deviance, and re-orienting toward the task-relevant stimulus feature (RON). Accuracy was reduced for deviant long tones, possibly due to withdrawing attention from processing the time information, making long stimuli appear shorter. This effect increased with age, and cluster-based permutation tests on the correlation of ERPs and age as well as linear mixed modeling indicated a decrease in MMN, an increase in P3a with long tones, and decreases in P3b and RON. This suggests a greater attentional orienting to the deviant stimulus feature and a reduced re-orienting to the task-relevant feature with increasing age.

Dietary patterns, inflammatory biomarkers and cognition in older adults: An analysis of three population-based cohorts

BACKGROUND

Targeting effective strategies to prevent cognitive decline is key in the aging population. Some diets have been linked to a slower cognitive decline, potentially through reducing inflammation. We aimed at determining the effect of inflammatory dietary patterns (IDPs) on cognitive function in three population-based cohorts.

METHODS

In this longitudinal study, we analyzed data from the Canadian Longitudinal Study of Aging, CoLaus|PsyCoLaus and Rotterdam Study. Our analytical sample included participants over 55 years old with baseline data on cognition, dietary intake, and inflammatory markers. IDPs were derived for each cohort using reduced rank regression to reflect maximal variation in three inflammatory markers. We calculated scores of consumption of the IDPs, higher scores indicating more IDP consumption. We used inverse probability of treatment and censoring weights in the marginal structural models to estimate associations of higher versus lower quarters of consumption of an IDP on general cognition (Mini-Mental State Evaluation) and four cognitive domains (memory, verbal fluency, verbal learning and processing speed and executive function) during at least 3 years of follow-up.

RESULTS

We included 10,366 participants (mean age 68) followed-up for a mean of 5 years. Diet explained between 1 and 2% of the variation of the inflammatory markers. There were no differences in general cognition when comparing the highest to the lowest quarter of consumption of IDPs among the three cohorts. Mean differences for the four cognitive domains were of small magnitude across cohorts and not clinically relevant.

CONCLUSION

Diet explained low variation in inflammatory markers. Consuming IDPs was not associated with mean differences in general or domain-specific cognitive function.

Association between blood pressure and dementia in older adults: a cross-sectional study from China

Background and aims

The association between blood pressure (BP) and dementia in older adults remains unclear, prompting this study to investigate the relationship between various BP indicators and dementia in this population.

Methods

A cross-sectional survey was conducted in 2019, including 3,599 participants aged 65 years or older. The basic demographic characteristics of participants were collected. BP measurements and neuropsychological assessments were performed. From the systolic BP (SBP) and diastolic BP (DBP) values, mean arterial pressure (MAP), pulse pressure (PP) and blood pressure index (BPI) were calculated. Generalized additive models and logistic regression models were used to analyze the association between BP indicators and dementia.

Results

Generalized additive models identified a U-shaped relationship between DBP and dementia, which was more significant in males and people 70 years of age and older. The optimal DBP associated with the lowest dementia risk was 85 mmHg. Logistic regression models revealed that compared to the DBP subgroup (80-89 mmHg), participants in the DBP < 80 mmHg subgroup and the DBP ≥100 mmHg subgroup had OR for dementia of 1.611 (95% CI: 1. 252-2.073, P < 0.001) and 1.423 (95% CI: 0.999-2.028, p = 0.050), respectively. A significant association was observed between BPI and dementia (OR:1.746 95% CI: 1.142-2.668, p = 0.010).

Conclusion

In older adults, we found a U-shaped relationship between DBP and dementia, and a linear relationship between BPI and dementia. These results underscore the importance of considering DBP and BPI in BP management strategies for older adults to potentially prevent or delay dementia onset.

Are subjective language complaints in memory clinic patients informative?

To diagnose mild cognitive impairment, it is crucial to understand whether subjective cognitive complaints reflect objective cognitive deficits. This question has mostly been investigated in the memory domain, with mixed results. Our study was one of the first to address it for language. Participants were 55-to-93-year-old memory clinic patients (n = 163). They filled in a questionnaire about subjective language and memory complaints and performed two language tasks (naming-by-definition and sentence comprehension). Greater language complaints were associated with two language measures, thus showing a moderate value in predicting language performance. Greater relative severity of language versus memory complaints was a better predictor, associated with three language performance measures. Surprisingly, greater memory complaints were associated with better naming, probably due to anosognosia in further disease progression or personality-related factors. Our findings highlight the importance of relative complaint severity across domains and, clinically, call for developing self-assessment questionnaires asking specific questions about multiple cognitive functions.

The Care Needs of Patients With Cognitive Impairment in Late-Stage Parkinson's Disease

BACKGROUND

Cognitive impairment is common in Parkinson's disease (PD), but care needs and resource use for those with significant cognitive impairment are not well established.

METHODS

675 participants with PD from the international Care of Late-Stage Parkinsonism (CLaSP) study were grouped into those without (n = 333, 49%) and with cognitive impairment (MMSE < 24/30 or diagnosis of dementia or Mild Cognitive Impairment; n = 342, 51%) and their clinical features, care needs and healthcare utilisation compared. The relationship between cognition and healthcare consultations was investigated through logistic regression.

RESULTS

Cognitive impairment was associated with more motor and non-motor symptoms, less antiparkinsonian but higher rates of dementia and antipsychotic medication, worse subjective health status and greater caregiver burden. A considerable proportion did not have a pre-established cognitive diagnosis. Care needs were high across the whole sample but higher in the cognitive impairment group. Home care and care home use was higher in the cognitive impairment group. However, use of healthcare consultations was similar between the groups and significantly fewer participants with cognitive impairment had had recent PD Nurse consultations. Worse cognitive impairment was associated with lower frequency of recent PD nurse and multidisciplinary therapy consultation (physiotherapy, massage, occupational therapy, speech training and general nursing).

CONCLUSIONS

Those with cognitive impairment have more severe PD, higher care needs and greater social care utilisation than those with normal cognition, yet use of health care services is similar or less. Cognitive impairment appears to be a barrier to PD nurse and multidisciplinary therapy consultations. This challenges current models of care: alternative models of care may be required to serve this population.

PLAIN LANGUAGE SUMMARY

Parkinson's disease is a long-term progressive health condition. Over time, many people with Parkinson's develop problems with thinking and memory, called cognitive impairment. This can negatively impact the daily lives of the person with Parkinson's and their caregiver. It is also thought to be a barrier to accessing healthcare. How people with Parkinson's who have cognitive impairment use healthcare and detail of their care needs is not well known.We analysed data from a large sample of people with advanced Parkinson's from six European countries to investigate their symptoms, care needs and healthcare use. We compared those with cognitive impairment to (342 people) to those without cognitive impairment (333 people).We found that those with cognitive impairment had more severe Parkinson's across a range of symptoms compared to those without cognitive impairment. They also had more care needs, reported their health status to be worse, and their caregivers experienced greater strain from caring. Whilst use of other healthcare services was similar between the two groups, those with cognitive impairment were less likely to have recently seen a Parkinson's nurse than those without cognitive impairment. Further analysis showed an association between cognitive impairment and not having seen a Parkinson's nurse or therapist recently, taking psychiatric symptoms, functional disability and care home residence into account. Therapists included were physiotherapy, massage, occupational therapy, speech training and general nursing. These findings highlight unmet need. We suggest that healthcare should be more targeted to help this group of people, given their higher care needs.

Combining the AD8 and MMSE for community-based dementia screening

BACKGROUND

This study aimed to determine whether a cognitive test the Mini-Mental State Examination (MMSE) and the Ascertain Dementia 8 (AD8) instrument applied in combination could improve the accuracy of dementia detection in a community setting.

METHODS

Study participants were recruited from a community-based integrated screening program in Tainan, Taiwan. Participants completed the AD8 and were administered the Chinese version of the MMSE by psychologists. In addition, the presence of dementia was determined by neurologists based on the 2011 National Institute on Aging-Alzheimer's Association guidelines. Logistic regression analysis determined whether the combination of these two tests provided any additional information for dementia detection than either test alone. Receiver operating characteristic (ROC) curve analyses were conducted to explore the performances of different screening modalities in detecting dementia.

RESULT

In total, 282 participants with an average age of 69.31 ± 10.27 years were enrolled. The prevalence of dementia among participants aged ≥65 years was 9.29 %. The sensitivity and specificity of the AD8 applied alone for detecting dementia were 64.71 % and 87.89 %, respectively, and of the MMSE applied alone, after adjusting for education level, were 41.18 % and 84.50 %, respectively. Using a cutoff score of 21 for the MMSE resulted in sensitivity of 77.78 % and specificity of 73.58 %. The AD8 and MMSE when combined in parallel yielded 88.89 % sensitivity and 70.16 % specificity. The serial use of the AD8 followed by the MMSE yielded 50 % sensitivity and 93.02 % specificity. Except for when an MMSE cutoff value of 26 was applied, the sensitivity of all examined modalities was poor and specificity was moderate for detecting mild cognitive impairment. ROC curve analysis revealed that the parallel application of the MMSE and AD8 (area under the ROC curve [AUC]: 82.3 % [75.1 %-89.4 %]) resulted in better dementia detection accuracy than the AD8 alone (AUC: 73.3 % [60.7 %-85.9 %]), the MMSE alone (AUC: 77.4 % [67.6 %-87.3 %]), or serial test administration (AUC: 67.6 % [53.4 %-81.8 %]).

CONCLUSION

This study successfully demonstrated that the MMSE and AD8 combination for dementia screening could improve detection accuracy in a community setting.

The use of audio-biographical cues in dementia care: a four-year evaluation in Swiss hospitals, care, and domestic homes

Introduction

In dementia care, the integration of innovative interventions is essential to enhancing the wellbeing and quality of life of people with dementia. Among these interventions, the Music Mirror intervention has emerged as a promising tool to provide personalized audio-biographical cues aimed at soothing, motivating, and engaging people with dementia. This study examined the effects of a Music Mirror intervention on the (a) wellbeing, emotions, and behavioral and psychological symptoms of 155 individuals with dementia, (b) perceived burden, relationship quality, and gains of their informal/formal caregivers, and (c) momentary closeness, wellbeing and stress of caregivers.

Methods

This four-year study employed a quasi-experimental waiting-control group design, utilizing before-after measurements in Swiss hospitals, care homes, and domestic homes. For four 6-week intervention phases, Music Mirrors, i.e., brief written resources of acoustic material, associated with practical activities of daily life, were applied at least twice a week by the caregivers during critical moments such as staff handover. Repeated measures' analysis of variance and other tests were used to analyze the data.

Results

Individuals with dementia had a higher wellbeing after the Music Mirror use across different care situations. While the Music Mirrors were played, individuals with dementia showed more positive than negative emotions at each measurement occasion, but emotion scores did not significantly change over time. After the MM use, caregivers felt better, closer to the person with dementia, and less stressed. Caregivers also reported significant gains at the end of the intervention. However, there were no significant changes in the frequency of the behavioral and psychological symptoms of dementia, care-related burden and relationship quality over time, regardless of the treatment condition.

Discussion

By incorporating personalized audio-biographical cues into their care routines, the wellbeing of people with dementia was improved as well as it had positive momentary effects on their caregivers. The Music Mirror intervention addresses the preferences and needs of people with dementia and helps build bonds between care-recipients and caregivers. Therefore, Music Mirrors can be seen as a highly adaptive and individualized instrument to improve momentary wellbeing of people with dementia in various care situations during daily life.

Increased Odds of Cognitive Impairment in Adults with Depressive Symptoms and Antidepressant Use

INTRODUCTION

The relationship between antidepressant use and class with cognition in depression is unclear. This study aimed to evaluate the association of cognition with depressive symptoms and antidepressant use (class, duration, number).

METHODS

Data from the National Health and Nutrition Examination Survey were examined for cognitive function through various tests and memory issues through the Medical Conditions questionnaire. Depressive symptoms were assessed using the Patient Health Questionnaire-9.

RESULTS

A total of 2867 participants were included. Participants with depressive symptoms had significantly higher odds of cognitive impairment (CI) on the animal fluency test (aOR=1.89, 95% CI=1.30, 2.73, P=0.002) and Digit Symbol Substitution test (aOR=2.58, 95% CI=1.34, 4.9, P=0.007), as well as subjective memory issues (aOR=7.25, 95% CI=4.26, 12.32, P<0.001) than those without depression. There were no statistically significant associations between any of the CI categories and depressive symptoms treated with an antidepressant and antidepressant use duration. Participants who were using more than one antidepressant had significantly higher odds of subjective memory issues than those who were using one antidepressant. Specifically, users of atypical antidepressants, selective serotonin reuptake inhibitors, or tricyclic antidepressants (TCAs) had significantly higher odds of subjective memory issues in comparison to no antidepressants, with TCAs showing the largest odds (aOR=4.21, 95% CI=1.19, 14.86, P=0.028).

DISCUSSION

This study highlights the relationship between depressive symptoms, antidepressant use, and CI. Future studies should further evaluate the mechanism underlying this phenomenon.

Association between frailty and cognitive status among ambulating Korean elderly: An observational study

We aimed to determine the association between frailty and cognitive status of the elderly population in Korea. We examined data from 9920 elders who participated in the 2020 Survey of Living Conditions and Welfare Needs of Korean Older Persons. Frailty was assessed using the Korean version of the Fatigue, Resistance, Ambulation, Illnesses, and Weight Loss scale. The Korean mini-mental status examination was used to test cognitive function. Several logistic regression analysis was performed, with correction for several confounding variables (socioeconomic, health behavior, psychological characteristics, and functional status), to evaluate the relationship between frailty and cognitive state. Of the elderly population in Korea, 1451 (14.6%) were frail and 5977 (60.3%) were pre-frail. Compared to the non-frail group (20.3%), cognitive impairment was considerably higher in the pre-frail (33.1%) and frail (39.8%) groups. When compared to the non-frail group, cognitive impairment was substantially linked to a higher risk of frailty after adjustment (pre-frail odds ratio [OR]: 1.66, 95% confidence interval [CI]: 1.47-1.88; frail OR: 2.00, 95% CI: 1.68-2.37). When cognitive impairment and frailty subcomponents were present, there was a higher likelihood of severe resistance (OR: 1.89; 95% CI: 1.70-2.11) and ambulation (OR: 1.46, 95% CI: 1.32-1.63) issues. Frailty is associated with cognitive impairment.

Comparison of the Diagnostic Accuracy of Five Cognitive Screening Tests for Diagnosing Mild Cognitive Impairment in Patients Consulting for Memory Loss

Objectives: We aimed to evaluate and compare the diagnostic capacity of five cognitive screening tests for the diagnosis of mild cognitive impairment (MCI) in patients consulting by memory loss. Methods: A cross-sectional study involving 140 participants with a mean age of 74.42 ± 7.60 years, 87 (62.14%) women. Patients were classified as MCI or cognitively unimpaired according to a comprehensive neuropsychological battery. The diagnostic properties of the following screening tests were compared: Mini-Mental State Examination (MMSE), Addenbrooke's Cognitive Examination III (ACE-III) and Mini-Addenbrooke (M-ACE), Memory Impairment Screen (MIS), Montreal Cognitive Assessment (MoCA), and Rowland Universal Dementia Assessment Scale (RUDAS). Results: The area under the curve (AUC) was 0.861 for the ACE-III, 0.867 for M-ACE, 0.791 for MoCA, 0.795 for MMSE, 0.731 for RUDAS, and 0.672 for MIS. For the memory components, the AUC was 0.869 for ACE-III, 0.717 for MMSE, 0.755 for MoCA, and 0.720 for RUDAS. Cronbach's alpha was 0.827 for ACE-III, 0.505 for MMSE, 0.896 for MoCA, and 0.721 for RUDAS. Correlations with Free and Cued Selective Reminding Test were moderate with M-ACE, ACE-III, and MoCA, and moderate for the other tests. The M-ACE showed the best balance between diagnostic capacity and time of administration. Conclusions: ACE-III and its brief version M-ACE showed better diagnostic properties for the diagnosis of MCI than the other screening tests. MoCA and MMSE showed adequate properties, while the diagnostic capacity of MIS and RUDAS was limited.

Association between vascular aging and cognitive function in Chinese adults

BACKGROUND

Vascular health has been associated with cognition but related evidence is limited in Chinese. The objective of this study was to examine the association of vascular aging assessed by arterial stiffness and blood pressure with cognitive function in an unselected Chinese population.

METHODS

In the Tianning Cohort (N = 5158), indicators of arterial stiffness and blood pressure including carotid-femoral pulse wave velocity (cfPWV), ankle-brachial index (ABI), pulse pressure (PP), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were measured. Cognitive function was assessed using the Mini Mental State Examination (MMSE) questionnaire. We applied Poisson regression and logistic regression to examine the associations of vascular aging and blood pressure with cognitive function.

RESULTS

76 (1.47%) participants had impaired cognitive function diagnosed by a MMSE score of less than 24 points. Participants with a higher level of PP were more likely to have a decreased score of MMSE (β=-0.0121, P < 0.001 for log-transformed pulse pressure) and a higher risk of having impaired cognitive function (OR = 5.95, 95%CI: 2.02-17.79, P < 0.001 for log-transformed PP). Per standard deviation increment in SBP was significantly associated with lower MMSE score (β=-0.0020, P < 0.001) and impaired cognitive function (OR = 1.69, 95%CI: 1.38-2.06, P < 0.001). No significant associations were found regarding other parameters.

CONCLUSIONS

Blood pressure and hypertension were associated with cognitive function in Chinese adults. PP may be a potential predictor for impaired cognitive function.

Treating Aortic Valve Stenosis for Vitality Improvement: The TAVI Study

BACKGROUND

Degenerative aortic valve stenosis (AS) is the most common valvular heart disease among the elderly. Once cardiac symptoms occur, current guidelines recommend aortic valve replacement. Progressive degeneration/calcification reduces leaflet mobility with gradual cardiac output (CO) impairment. Low CO might induce abnormal brain-aging with cognitive impairment and increased risk of dementia, such as Alzheimer's disease or vascular dementia. On the contrary, cognitive improvement has been reported in patients in whom CO was restored. Transcatheter aortic valve implantation (TAVI) has proven to be a safe alternative to conventional surgery, with a similar mid-term survival and stroke risk even in low-risk patients. TAVI is associated with an immediate CO improvement, also effecting the cerebrovascular system, leading to an increased cerebral blood flow. The correlation between TAVI and cognitive improvement is still debated. The present study aims at evaluating this relationship in a cohort of AS patients where cognitive assessment before and after TAVI was available.

METHODS

a total of 47 patients were retrospectively selected. A transcranial Doppler ultrasound (TCD) before and after TAVI, a quality of life (QoL) score, as well as a mini-mental state examination (MMSE) at baseline and up to 36 months, were available.

RESULTS

TAVI was associated with immediate increase in mean cerebral flow at TCD. MMSE slowly increase at 36-months follow-up with improved QoL mainly for symptoms, emotions and social interactions.

CONCLUSIONS

this proof-of-concept study indicates that TAVI might induce cognitive improvement in the long-term as a result of multiple factors, such as cerebral flow restoration and a better QoL.

Meta-analysis on the interrelationship between sarcopenia and mild cognitive impairment, Alzheimer's disease and other forms of dementia

Sarcopenia has been associated with adverse health outcomes, including cognitive dysfunction. However, its specific interrelationship with neurocognitive disorders such as mild cognitive impairment (MCI), Alzheimer's disease (AD) or other types of dementia has not been thoroughly explored. This meta-analysis aims to summarize the existing evidence on this interrelationship. This systematic review was pre-registered on PROSPERO (CRD42022366309) and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. Databases, including PubMed, Embase, CINAHL, Scopus, Web of Science, PEDro, SPORTDiscus and the Cochrane Central Register of Controlled Trials, and the data registry ClinicalTrials.gov were searched from inception to 8 June 2023. Observational studies (cross-sectional and cohort) and interventional studies reporting on the association and prevalence of sarcopenia in MCI, AD or other types of dementia in adults ≥50 years were included. For the meta-analysis, pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated for the association of sarcopenia with the neurocognitive disorders using random-effects/fixed-effects models. Subgroup analyses were performed to identify potential sources of heterogeneity. A total of 77 studies consisting of 92 058 subjects were finally included in the qualitative analysis (71 cross-sectional, 4 cohort and 2 interventional studies). Studies were heterogeneous, using different diagnostic criteria to define both sarcopenia and cognitive status. The majority of studies (n = 38) included Asian community-dwelling older adults. Most studies investigated the association of sarcopenia with AD (33/77) and MCI (32/77). For studies focusing on other forms of dementia, two studies included Lewy body dementia and one study included Parkinson's dementia, whereas the remaining studies did not specify dementia aetiology (n = 21). Three cohort studies explored the association between sarcopenia and incident MCI, whereas only one cohort study explored the association between dementia and incident sarcopenia. Two interventional studies investigated whether an exercise programme could prevent the progression of sarcopenia in older adults with dementia or AD. The information for the meta-analysis was extracted from 26 studies. Sarcopenia was significantly associated with MCI (pooled OR = 1.58, 95% CI 1.42-1.76) (n = 14), AD (pooled OR = 2.97, 95% CI 2.15-4.08) (n = 3) and non-AD dementia (pooled OR = 1.68, 95% CI 1.09-2.58) (n = 9). The significance and magnitude of the associations differed in subgroup analyses by study design, population, definition of sarcopenia or used tool to measure cognitive status. This meta-analysis showed that sarcopenia is significantly associated with MCI, AD and other types of dementia. These findings suggest the importance of early screening and prevention of sarcopenia in older people with cognitive dysfunction, although further longitudinal research is needed to clarify the causal relationship.

The mediating effect of the amygdala-frontal circuit on the association between depressive symptoms and cognitive function in Alzheimer's disease

Depressive symptoms occur commonly in Alzheimer's disease (AD). Although abnormalities in the amygdala-frontal circuit have been linked to emotional dysregulation and cognitive impairment, the neurological basis underlying these associations in AD patients with depressive symptoms (ADD) is unclear. We aimed to investigate the relationship between the amygdala-frontal circuit and depressive symptoms and cognitive function in ADD. We recruited 60 ADD, 60 AD patients without depressive symptoms (ADND), and 60 healthy controls (HC). Functional connectivity (FC) maps of the bilateral amygdala were compared. Fractional anisotropy (FA) of the amygdala-frontal circuit connected by the uncinate fasciculus (UF) was calculated using automated fiber quantification (AFQ). In addition, mediation analysis was performed to explore the effects of the amygdala-frontal circuit on the relationship between depressive symptoms and cognitive function. We found decreased bilateral amygdala FC with the inferior frontal gyrus (IFG) in the ADD group compared to the ADND and HC groups. Moreover, FA in the left frontal UF (nodes 64-97) was significantly lower in the ADD group than ADND group. Notably, amygdala-based FC with IFG and the left frontal UF FA mediated the relationship between depressive symptoms and cognitive function in ADD, with mediating effects ranging between 15 and 18%. Our study is the first to demonstrate the mediating effect of functional and microstructural abnormalities in the amygdala-frontal circuit in ADD. The findings suggest that the amygdala-frontal circuit may underlie emotional dysregulation in ADD, providing potential targets for treatment strategies.

Impact of SARS-CoV-2 infection on the cognitive functioning of patients institutionalized in nursing homes

BACKGROUND

COVID-19 disease affected the cognitive level of institutionalized patients in nursing homes, especially in the older subjects regardless of gender. This study aims to assess cognitive impairment using the Mini-Mental State Examination (MMSE) before and after COVID-19 infection, and to determine whether these changes varied based on gender.

METHODS

A pre- and post-COVID-19 study was conducted, involving 68 geriatric patients (34 men and 34 women) from two nursing homes. Cognitive impairment was assessed using the MMSE.

RESULTS

COVID-19 infection had a notable impact on the cognitive health of older adults residing in nursing homes, primarily attributed to the social isolation they experienced. This effect was more pronounced in older individuals. A comparison of the MMSE results by gender before and after contracting COVID-19 revealed significant differences in attention and calculation, with women obtaining the worst score before the virus. However, following their recovery from the virus, men demonstrated significantly lower scores in time and space orientation and evocation.

CONCLUSION

COVID-19 has led to a decline in cognitive functioning, significantly worsening the mental state of older individuals, even after recovery from the virus. Consequently, it is crucial to implement proactive measures to prevent isolation and safeguard the cognitive well-being of this vulnerable population.

Use of cortical hemodynamic responses in digital therapeutics for upper limb rehabilitation in patients with stroke

BACKGROUND

Stroke causes long-term disabilities, highlighting the need for innovative rehabilitation strategies for reducing residual impairments. This study explored the potential of functional near-infrared spectroscopy (fNIRS) for monitoring cortical activation during rehabilitation using digital therapeutics.

METHODS

This cross-sectional study included 18 patients with chronic stroke, of whom 13 were men. The mean age of the patients was 67.0 ± 7.1 years. Motor function was evaluated through various tests, including the Fugl-Meyer assessment for upper extremity (FMA-UE), grip and pinch strength test, and box and block test. All the patients completed the digital rehabilitation program (MotoCog®, Cybermedic Co., Ltd., Republic of Korea) while being monitored using fNIRS (NIRScout®, NIRx Inc., Germany). Statistical parametric mapping (SPM) was employed to analyze the cortical activation patterns from the fNIRS data. Furthermore, the K-nearest neighbor (K-NN) algorithm was used to analyze task performance and fNIRS data to classify the severity of motor impairment.

RESULTS

The participants showed diverse task performances in the digital rehabilitation program, demonstrating distinct patterns of cortical activation that correlated with different motor function levels. Significant activation was observed in the ipsilesional primary motor area (M1), primary somatosensory area (S1), and contralateral prefrontal cortex. The activation patterns varied according to the FMA-UE scores. Positive correlations were observed between the FMA-UE scores and SPM t-values in the ipsilesional M1, whereas negative correlations were observed in the ipsilesional S1, frontal lobe, and parietal lobe. The incorporation of cortical hemodynamic responses with task scores in a digital rehabilitation program substantially improves the accuracy of the K-NN algorithm in classifying upper limb functional levels in patients with stroke. The accuracy for tasks, such as the gas stove-operation task, increased from 44.4% using only task scores to 83.3% when these scores were combined with oxy-Hb t-values from the ipsilesional M1.

CONCLUSIONS

The results advocated the development of tailored digital rehabilitation strategies by combining the behavioral and cerebral hemodynamic data of patients with stroke. This approach aligns with the evolving paradigm of personalized rehabilitation in stroke recovery, highlighting the need for further extensive research to optimize rehabilitation outcomes.

Overlooked cases of mild cognitive impairment: Implications to early Alzheimer's disease

Mild cognitive impairment (MCI) marks the initial phase of memory decline or other cognitive functions like language or spatial perception, while individuals typically retain the capacity to carry out everyday tasks independently. Our comprehensive article investigates the intricate landscape of cognitive disorders, focusing on MCI and Alzheimer's disease (AD) and Alzheimer's disease-related dementias (ADRD). The study aims to understand the signs of MCI, early Alzheimer's disease, and healthy brain aging while assessing factors influencing disease progression, pathology development and susceptibility. A systematic literature review of over 100 articles was conducted, emphasizing MCI, AD and ADRD within the elderly populations. The synthesis of results reveals significant findings regarding ethnicity, gender, lifestyle, comorbidities, and diagnostic tools. Ethnicity was found to influence MCI prevalence, with disparities observed across diverse populations. Gender differences were evident in cognitive performance and decline, highlighting the need for personalized management strategies. Lifestyle factors and comorbidities were identified as crucial influencers of cognitive health. Regarding diagnostic tools, the Montreal Cognitive Assessment (MoCA) emerged as superior to the Mini-Mental State Examination (MMSE) in early MCI detection. Overall, our article provides insights into the multifaceted nature of cognitive disorders, emphasizing the importance of tailored interventions and comprehensive assessment strategies for effective cognitive health management.

Exploration of the application of Picture-Based Memory Impairment Screen in stroke patients in a preliminary study

Objective The objective was to explore the validity and reliability of the Picture-Based Memory Impairment Screen (PMIS) assessment tool in stroke patients and to provide an objective basis for its application in China.Methods: A total of 30 stroke patients in the Department of Rehabilitation Medicine were assessed using the Mini-Mental State Examination (MMSE), the Montreal Cognitive Assessment (MoCA), and the PMIS. The results were evaluated by content validity, simultaneous validity, consistency test of instruments of assessment, inter-scorer reliability, and retest reliability.Results: The correlation coefficient between each item score and total score of PMIS was between 0.422 and 0.778 (p < 0.05), showing good content validity. The total score of PMIS was moderately positively correlated with the MMSE short-term memory score (p < 0.001), highly positively correlated with the MMSE long-term memory score and retrospective memory score (p < 0.001), and highly positively correlated with the MoCA long-term memory score, memory index and total score (p < 0.001), indicating good criterion validity. The consistency test of the two instruments of assessment showed that a PMIS ≤ 5 was used as the demarcation score for dementia, and it was tested for consistency with the MMSE dementia score of stroke patients, and the Kappa value was 0.81 (p < 0.001). The inter-scorer reliability and retest reliability were good (inter-scorer reliability intra-group correlation coefficient (ICC) >0.95; retest reliability ICC 0.904).Conclusion: The PMIS was a reliable and valid assessment tool, which can be used as memory impairment screening tool for stroke patients in China.

Linking Cognitive Integrity to Working Memory Dynamics in the Aging Human Brain

Aging is accompanied by a decline of working memory, an important cognitive capacity that involves stimulus-selective neural activity that persists after stimulus presentation. Here, we unraveled working memory dynamics in older human adults (male and female) including those diagnosed with mild cognitive impairment (MCI) using a combination of behavioral modeling, neuropsychological assessment, and MEG recordings of brain activity. Younger adults (male and female) were studied with behavioral modeling only. Participants performed a visuospatial delayed match-to-sample task under systematic manipulation of the delay and distance between sample and test stimuli. Their behavior (match/nonmatch decisions) was fit with a computational model permitting the dissociation of noise in the internal operations underlying the working memory performance from a strategic decision threshold. Task accuracy decreased with delay duration and sample/test proximity. When sample/test distances were small, older adults committed more false alarms than younger adults. The computational model explained the participants' behavior well. The model parameters reflecting internal noise (not decision threshold) correlated with the precision of stimulus-selective cortical activity measured with MEG during the delay interval. The model uncovered an increase specifically in working memory noise in older compared with younger participants. Furthermore, in the MCI group, but not in the older healthy controls, internal noise correlated with the participants' clinically assessed cognitive integrity. Our results are consistent with the idea that the stability of working memory contents deteriorates in aging, in a manner that is specifically linked to the overall cognitive integrity of individuals diagnosed with MCI.

Screening instruments of cognition: The relation of the mini-mental state examination to the Edinburgh cognitive and behavioural ALS screen in amyotrophic lateral sclerosis

OBJECTIVE

The Edinburgh Cognitive and Behavioural ALS Screen (ECAS) is an established cognitive screening instrument for patients with amyotrophic lateral sclerosis (ALS). Different from tools like the Mini-Mental State Examination (MMSE), it is adjusted for motor impairment, yet, the latter remains one of the most widely used screening instruments, also in ALS studies. Thus, it is of utmost importance to relate outcome scores of both instruments to allow for comparison in ALS patients. This study reports on the performance of ALS patients in both tests with regard to incidence and degree of cognitive impairment, and the correspondence of both, ECAS and MMSE scores.

METHODS

We examined N = 84 ALS patients with the German versions of the ECAS and the MMSE. Performance in both tests regarding incidence and degree of cognitive impairment, and correspondence of frequency of cognitive impairment according to both tests was examined. The relationship between ECAS and MMSE scores was modelled with a non-linear regression model.

RESULTS

All ALS patients were able to complete the ECAS, 89.3% (N = 75) were capable to complete the MMSE. Prevalence of cognitive impairment was in both tests 22.7%, however agreement was only 52.9%. Despite, regression analyses yielded a strong positive relationship (adjusted R2 = .68) between the ECAS total score and the MMSE total score. Both tests were able to identify all patients with dementia.

CONCLUSION

These results suggest that the MMSE is not ideal for cognitive screening in early-stage ALS patients. However, a rough translation of MMSE scores in ECAS scores is possible to estimate the cognitive performance level of patients, with the ECAS being more discriminative in the lower range of cognitive dysfunction (ECAS score: 80-136), for which the MMSE does not define cognitive impairment (corresponding MMSE score: 27-30).

Neuropsychological Assessment for Early Detection and Diagnosis of Dementia: Current Knowledge and New Insights

Dementia remains an underdiagnosed syndrome, and there is a need to improve the early detection of cognitive decline. This narrative review examines the role of neuropsychological assessment in the characterization of cognitive changes associated with dementia syndrome at different states. The first section describes the early indicators of cognitive decline and the major barriers to their identification. Further, the optimal cognitive screening conditions and the most widely accepted tests are described. The second section analyzes the main differences in cognitive performance between Alzheimer's disease and other subtypes of dementia. Finally, the current challenges of neuropsychological assessment in aging/dementia and future approaches are discussed. Essentially, we find that current research is beginning to uncover early cognitive changes that precede dementia, while continuing to improve and refine the differential diagnosis of neurodegenerative disorders that cause dementia. However, neuropsychology faces several barriers, including the cultural diversity of the populations, a limited implementation in public health systems, and the adaptation to technological advances. Nowadays, neuropsychological assessment plays a fundamental role in characterizing cognitive decline in the different stages of dementia, but more efforts are needed to develop harmonized procedures that facilitate its use in different clinical contexts and research protocols.

Regional brain aging: premature aging of the domain general system predicts aphasia severity

Premature brain aging is associated with poorer cognitive reserve and lower resilience to injury. When there are focal brain lesions, brain regions may age at different rates within the same individual. Therefore, we hypothesize that reduced gray matter volume within specific brain systems commonly associated with language recovery may be important for long-term aphasia severity. Here we show that individuals with stroke aphasia have a premature brain aging in intact regions of the lesioned hemisphere. In left domain-general regions, premature brain aging, gray matter volume, lesion volume and age were all significant predictors of aphasia severity. Increased brain age following a stroke is driven by the lesioned hemisphere. The relationship between brain age in left domain-general regions and aphasia severity suggests that degradation is possible to specific brain regions and isolated aging matters for behavior.

Classifying Alzheimer's disease and normal subjects using machine learning techniques and genetic-environmental features

BACKGROUND

Alzheimer's disease (AD) is complicated by multiple environmental and polygenetic factors. The accuracy of artificial neural networks (ANNs) incorporating the common factors for identifying AD has not been evaluated.

METHODS

A total of 184 probable AD patients and 3773 healthy individuals aged 65 and over were enrolled. AD-related genes (51 SNPs) and 8 environmental factors were selected as features for multilayer ANN modeling. Random Forest (RF) and Support Vector Machine with RBF kernel (SVM) were also employed for comparison. Model results were verified using traditional statistics.

RESULTS

The ANN achieved high accuracy (0.98), sensitivity (0.95), and specificity (0.96) in the intrinsic test for AD classification. Excluding age and genetic data still yielded favorable results (accuracy: 0.97, sensitivity: 0.94, specificity: 0.96). The assigned weights to ANN features highlighted the importance of mental evaluation, years of education, and specific genetic variations (CASS4 rs7274581, PICALM rs3851179, and TOMM40 rs2075650) for AD classification. Receiver operating characteristic analysis revealed AUC values of 0.99 (intrinsic test), 0.60 (TWB-GWA), and 0.72 (CG-WGS), with slightly lower AUC values (0.96, 0.80, 0.52) when excluding age in ANN. The performance of the ANN model in AD classification was comparable to RF, SVM (linear kernel), and SVM (RBF kernel).

CONCLUSION

The ANN model demonstrated good sensitivity, specificity, and accuracy in AD classification. The top-weighted SNPs for AD prediction were CASS4 rs7274581, PICALM rs3851179, and TOMM40 rs2075650. The ANN model performed similarly to RF and SVM, indicating its capability to handle the complexity of AD as a disease entity.

Visit-to-visit variability in multiple biological measurements and cognitive performance and risk of cardiovascular disease: A cohort study

Background

Visit-to-visit variability in single biological measurements has been associated with cognitive decline and an elevated risk of cardiovascular diseases (CVD). However, the effect of visit-to-visit variability in multiple biological measures is underexplored. We investigated the effect of visit-to-visit variability in blood pressure (BP), heart rate (HR), weight, fasting plasma glucose, cholesterol, and triglycerides on cognitive performance and CVD.

Methods

Data on BP, HR, weight, glucose, cholesterol, and triglycerides from study visits in the Outcome Reduction with Initial Glargine Intervention (ORIGIN) trial were used to estimate the association between visit-to-visit variability, cognitive performance (Mini Mental State Examination (MMSE) score) and CVD (non-fatal stroke, non-fatal myocardial infarction, or cardiovascular death). Visit-to-visit variation for each measurement was estimated by calculating each individuals visit-to-visit standard deviation for that measurement. Participants whose standard deviation was in the highest quarter were classified as having high variation. Participants were grouped into those having 0, 1, 2, 3, or ≥ 4 high variation measurements. Regression and survival models were used to estimate the association between biological measures with MMSE and CVD with adjustment for confounders and mean measurement value.

Results

After adjustment for covariates, higher visit-to-visit variability in BP, HR, weight, and FPG were associated with poorer MMSE and a higher risk of CVD. Effect sizes did not vary greatly by measurement. The effects of high visit-to-visit variability were additive; compared to participants who had no measurements with high visit-to-visit variability, those who had high visit-to-visit variability in ≥4 measurements had poorer MMSE scores (-0.63 (95 % CI -0.96 to -0·31). Participants with ≥4 measurements with high visit-to-visit variability compared to participants with none had higher risk of CVD (hazard ratio 2.46 (95 % CI 1.63 to 3.70).

Conclusion

Visit-to-visit variability in several measurements were associated with cumulatively poorer cognitive performance and a greater risk of CVD.

Healthcare burden of cognitive impairment: Evidence from a Singapore Chinese health study

Background

Cognitive impairment (CI) raises risks for unplanned healthcare utilisation and expenditures and for premature mortality. It may also reduce risks for planned expenditures. Therefore, the net cost implications for those with CI remain unknown.

Method

We examined differences in healthcare utilisation and cost between those with and without CI. Using administrative healthcare utilisation and cost data linked to the Singapore Chinese Health Study cohort, we estimated regression-adjusted differences in annual healthcare utilisation and costs by CI status determined by modified Mini-Mental State Exam. Estimates were stratified by ex ante mortality risk constructed from out-of-sample Cox model predictions applied to the full sample, with a separate analysis restricted to decedents. These estimates were used to project differential healthcare costs by CI status over 5 years.

Results

Patients with CI had 17% higher annual cost compared to those without CI (SGD4870 versus SGD4177, P<0.01). Accounting for the greater mortality risk, individuals with CI cost 9% to 17% more over 5 years, or SGD2500 (95% confidence interval 1000-4200) to SGD3600 (95% confidence interval 1300-6000) more, depending on their age. Higher cost was mainly due to more emergency department visits and subsequent admissions (i.e. unplanned). Differences attenuated in the last year of life when costs increased dramatically for both groups.

Conclusion

Ageing populations and higher rates of CI will further strain healthcare resources primarily through greater use of emergency department visits and unplanned admissions. Efforts should be made to identify at risk patients with CI and take appropriate remediation strategies.

Relationship of Hearing Loss to Parkinson's Disease, Dementia, and APOE Genotype in Adults

Background: Hearing loss has been recognized as a risk factor for dementia and non-motor features of Parkinson's disease (PD). The apolipoprotein E (APOE) protein contributes to maintenance and repair of neuronal cell membranes, causing age-related disorders. This study aimed to analyze the impact of hearing loss on cognitive impairment, PD severity, and APOE gene expression in these patients. Methods: A total of 72 out-patients diagnosed with either PD or hearing loss were enrolled in this study. The hearing assessment included pure-tone audiometry, speech reception thresholds, and speech discrimination ability. Dementia was assessed by filling out the Clinical Dementia Rating and Mini-Mental State Examination questionnaires. The severity of PD was assessed using the Modified Hoehn and Yahr scale. Blood samples were tested for the gene expression of APOE. Results: Out of the 72 cases, there were 44 males and 28 females, with an average age of 64.4 ± 9.1 years. A total of 41 out of 72 cases had dementia and had a worse hearing threshold than those without dementia (47.1 ± 24.4 vs. 31.7 ± 22.1 dB, p = 0.006). A total of 58 patients were diagnosed with PD, with 14 of them classified as having severe symptoms (Modified Hoehn and Yahr scale > 2). Patients with severe PD were found to have a worse hearing threshold (49.6 ± 28.3 vs. 30.3 ± 17.8 dB, p = 0.028) and higher prevalence of dementia (12/14 vs. 18/44, p = 0.006). Among 10 individuals with the APOE ε4 gene, the prevalence of dementia was higher than those without the ε4 allele (9/10 vs. 32/62, p = 0.036). Conclusions: Hearing loss is common in severe PD and in dementia patients. Severe PD has a negative impact on the hearing threshold and cognitive dysfunction. Patients with APOE ε4 have a higher prevalence of dementia.

Color discrimination in fixed saturation level of patients with acute traumatic injury

Introduction

Traumatic brain injury (TBI) is an important public health concern and that may lead to severe neural sequels, such as color vision deficits.

Methods

We evaluated the color vision of 10 TBI patients with normal cognitive function using a color discrimination test in a fixed saturation level. We also analyzed computerized tomography scans to identify the local of the brain damages.

Results

Four TBI patients that had lesions in brain areas of the ventral visual streams, five TBI patients had lesions inferred in brain areas of the dorsal visual stream, and one TBI patient had lesion in the occipital area. All the patients had cognitive and color vision screened and they had characterized the chromatic discrimination at high and low saturation. All participants had no significant cognitive impairment in the moment of the color vision test. Additionally, they had perfect performance for discrimination of chromatic stimulus at high saturation and similar to controls (n = 37 age-matched participants). Three of four TBI patients with lesions in the ventral brain and one patient with lesion in the occipital area had impairment of the chromatic discrimination at low saturation. All TBI patients with lesions in the dorsal brain had performance similar or slightly worse than the controls.

Conclusion

Chromatic discrimination at low saturation was associated to visual damage in the ventral region of the brain and is a potential tool for functional evaluation of brain damage in TBI patients.

Temperament Based Personality Types in Community-Dwelling Older Adults: A Latent Profile Analysis

Three adaptive trait-based personality types have been replicated across ages, cultures, clinical problems and clustering methods: Resilient, Undercontrolled and Overcontrolled type (RUO). Recently there is growing interest in and importance of biopsychosocial transdiagnostic factors underlying personality types, such as temperamental reactivity and self-regulation. Latter can be understood in terms of Behavioural Inhibition (BIS), Behavioural Activation Systems (BAS) and Effortful Control (EC). The occurrence of temperament based RUO types has not yet been confirmed in older adults with or without a mental disorder. Therefore, based on a person-centered approach, the current study investigates whether RUO types can be corroborated in older adults based on the aforementioned temperamental factors. Latent profile analysis yielded two distinct personality profiles in community-dwelling over-60s, which we tentatively labeled a resilient (n = 167) and overcontrolled/inhibited type (n = 241). Compared to the resilient type, the overcontrolled/inhibited type scored lower on EC and higher on BIS. We could not corroborate an undercontrolled type (profiles scored equally on BAS). Group comparisons revealed that overcontrolled/inhibited older adults demonstrated significantly more clinical symptoms, higher emotional instability, lower scores on adaptive traits, less resilience and were significantly more likely to use passive and avoidant coping styles, compared to resilient older adults.

Evaluation of Differential Diagnostics Potential of Uniform Data Set 2 Neuropsychology Battery Using Alzheimer's Disease Biomarkers

OBJECTIVE

This study aims to evaluate the efficacy of the Uniform Data Set (UDS) 2 battery in distinguishing between individuals with mild cognitive impairment (MCI) attributable to Alzheimer's disease (MCI-AD) and those with MCI due to other causes (MCI-nonAD), based on contemporary AT(N) biomarker criteria. Despite the implementation of the novel UDS 3 battery, the UDS 2 battery is still used in several non-English-speaking countries.

METHODS

We employed a cross-sectional design. A total of 113 Czech participants with MCI underwent a comprehensive diagnostic assessment, including cerebrospinal fluid biomarker evaluation, resulting in two groups: 45 individuals with prodromal AD (A+T+) and 68 participants with non-Alzheimer's pathological changes or normal AD biomarkers (A-). Multivariable logistic regression analyses were employed with neuropsychological test scores and demographic variables as predictors and AD status as an outcome. Model 1 included UDS 2 scores that differed between AD and non-AD groups (Logical Memory delayed recall), Model 2 employed also Letter Fluency and Rey's Auditory Verbal Learning Test (RAVLT). The two models were compared using area under the receiver operating characteristic curves. We also created separate logistic regression models for each of the UDS 2 scores.

RESULTS

Worse performance in delayed recall of Logical Memory significantly predicted the presence of positive AD biomarkers. In addition, the inclusion of Letter Fluency RAVLT into the model significantly enhanced its discriminative capacity.

CONCLUSION

Our findings demonstrate that using Letter Fluency and RAVLT alongside the UDS 2 battery can enhance its potential for differential diagnostics.

A novel speech analysis algorithm to detect cognitive impairment in a Spanish population

Objective

Early detection of cognitive impairment in the elderly is crucial for diagnosis and appropriate care. Brief, cost-effective cognitive screening instruments are needed to help identify individuals who require further evaluation. This study presents preliminary data on a new screening technology using automated voice recording analysis software in a Spanish population.

Method

Data were collected from 174 Spanish-speaking individuals clinically diagnosed as cognitively normal (CN, n = 87) or impaired (mild cognitive impairment [MCI], n = 63; all-cause dementia, n = 24). Participants were recorded performing four common language tasks (Animal fluency, alternating fluency [sports and fruits], phonemic "F" fluency, and Cookie Theft Description). Recordings were processed via text-transcription and digital-signal processing techniques to capture neuropsychological variables and audio characteristics. A training sample of 122 subjects with similar demographics across groups was used to develop an algorithm to detect cognitive impairment. Speech and task features were used to develop five independent machine learning (ML) models to compute scores between 0 and 1, and a final algorithm was constructed using repeated cross-validation. A socio-demographically balanced subset of 52 participants was used to test the algorithm. Analysis of covariance (ANCOVA), covarying for demographic characteristics, was used to predict logistically-transformed algorithm scores.

Results

Mean logit algorithm scores were significantly different across groups in the testing sample (p < 0.01). Comparisons of CN with impaired (MCI + dementia) and MCI groups using the final algorithm resulted in an AUC of 0.93/0.90, with overall accuracy of 88.4%/87.5%, sensitivity of 87.5/83.3, and specificity of 89.2/89.2, respectively.

Conclusion

Findings provide initial support for the utility of this automated speech analysis algorithm as a screening tool for cognitive impairment in Spanish speakers. Additional study is needed to validate this technology in larger and more diverse clinical populations.

Effects of self-monitoring using an accelerometer on physical activity of older people with long-term care insurance in Japan: a randomized controlled trial

PURPOSE

This study aimed to investigate the effects of a self-monitoring intervention to promote an increase in physical activity, as measured by step count, and reduce sedentary behavior in older people covered by the long-term care insurance system (LTCI) in Japan.

METHODS

This was a randomized controlled trial conducted at a daycare center from October 2022 to January 2023. Fifty-two older adults with LTCI who were able to walk with or without aids were assigned to an intervention (n = 26) group and control (n = 26) group. During the 5-week follow-up period, the intervention group received education on physical activity and self-monitoring such as goal setting, self-management and feedback. The primary outcome was step count, and the secondary outcome was sedentary behavior.

RESULTS

Participants who completed the study to the end of the 5-week follow-up and drop-out participants for whom outcome data were available were included in the final analysis of 57 participants, n = 24 (79.8 ± 8.8 years, male 25.5%) in the intervention group and n = 23 (82.5 ± 8.5 years, male 39.1%) in the control group. Comparisons between the two groups at baseline showed no significant differences. In the results of a two-way mixed analysis of variance (ANOVA) including 2 (group: control, intervention) × 2 (term: baseline, 5-week follow-up) factors, an interaction was observed in the number of steps, sedentary behavior, and light physical activity (p < 0.05).

CONCLUSION

Self-monitoring of physical activity using an accelerometer may be effective in increasing the number of steps and light physical activity and in reducing sedentary behavior in older people with LTCI.

CLINICAL TRIAL REGISTRATION

UMIN000052044, registered on 2023/08/29.

Taste preferences, cardiometabolic diseases and mild cognitive impairment: a prospective cohort analysis of older Chinese adults

Taste preference is a pivotal predictor of nutrient intake, yet its impact on mild cognitive impairment (MCI) remains poorly understood. We aimed to investigate the association between taste preferences and MCI and the role of cardiometabolic diseases (CMD) in this association. The study included older adults, aged 65-90 years, with normal cognitive function at baseline who were enrolled in the Chinese Longitudinal Healthy Longevity Survey (CLHLS) from 2008 to 2018. MCI was measured by the Mini-Mental State Examination, and multivariable Cox regression models were applied. Among 6423 participants, 2534 (39·45 %) developed MCI with an incidence rate of 63·12 - per 1000 person-years. Compared with individuals with insipid taste, those preferring sweetness or spiciness had a higher MCI risk, while saltiness was associated with a lower risk. This association was independent of objective dietary patterns and was more pronounced among urban residents preferring sweetness and illiterate participants preferring spiciness. Notably, among sweet-liking individuals, those with one CMD experienced a significant detrimental effect, and those with co-occurring CMD had a higher incidence rate of MCI. Additionally, regional variations were observed: sweetness played a significant role in regions known for sweet cuisine, while the significance of spiciness as a risk factor diminishes in regions where it is commonly preferred. Our findings emphasize the role of subjective taste preferences in protecting cognitive function and highlight regional variations. Target strategies should focus on assisting individuals with CMD to reduce excessive sweetness intake and simultaneously receiving treatment for CMD to safeguard cognitive function.

Longitudinal trajectories of cognitive decline and cerebral blood flow abnormalities in octogenarian men with normal global cognition

Aims

Cognitive and perfusion changes have been previously observed in older men with Mini Mental State Examination scores>24 points. We aimed to investigate time change in cognitive domains in a cohort of non-demented men between age 68 and 82, and how they are expressed in regional defects estimated by Cerebral Blood Flow (rCBF).

Methods

103 men at age 81 with MMSE scores >24 (mean 28.4 ± 1.7), no dementia or stroke, were examined with the same cognitive test battery at age 68 and age 81: Synonyms (SRB-1), Block design (SRB-3), Paired Associates, Digit Symbol Substitution and Benton Visual Retention test. rCBF was estimated using 99mTc-HMPAO SPECT at age 82.

Results

Between ages 68 and 82 we observed a relative decline (Δ%) of cognitive test scores: SRB-3 and Benton tests, -33.7 % (SD 16,8) and -25.8 % (SD 23.9) respectively, followed by Digit Symbol test: -22,6 % (SD 15,6). The cluster of men (46 %) could be detected, grouped on the largest test score decline and highest overall test predictors' importance in decreasing order: Δ% SRB-3, Δ% Paired Associates, Δ% Digit Symbol, Δ% Benton VR and Δ% SRB-1. Compared to the cluster with stable cognitive functions, it expressed lower rCBF in frontal and parietal lobes, and in subcortical areas.

Conclusion

Nearly half of the studied, community-dwelling cohort of non-demented, octogenarian men with MMSE > 24, had a combination of decreasing visuospatial ability and episodic memory during preceding years, expressed by widespread rCBF changes in fronto-subcortical areas.

Cognitive impairment in Chinese traumatic brain injury patients: from challenge to future perspectives

Traumatic Brain Injury (TBI) is a prevalent form of neurological damage that may induce varying degrees of cognitive dysfunction in patients, consequently impacting their quality of life and social functioning. This article provides a mini review of the epidemiology in Chinese TBI patients and etiology of cognitive impairment. It analyzes the risk factors of cognitive impairment, discusses current management strategies for cognitive dysfunction in Chinese TBI patients, and summarizes the strengths and limitations of primary testing tools for TBI-related cognitive functions. Furthermore, the article offers a prospective analysis of future challenges and opportunities. Its objective is to contribute as a reference for the prevention and management of cognitive dysfunction in Chinese TBI patients.

The Effectiveness of Cognitive-Focused Interventions for Adults With Diabetes: A Systematic Review

BACKGROUND

Adults with diabetes and impaired memory and executive functions are more likely to experience difficulties in diabetes self-management and achieving glycemic targets. The purpose of this systematic review was to evaluate the evidence of the effects of cognitive-focused interventions on cognitive ability, diabetes self-management, and management of glycemic levels for middle-aged adults and older adults with diabetes.

METHODS

A systematic review of randomized controlled/clinical trials published in English between 2012 and 2022 was conducted. A search was performed using 5 databases (PubMed, CINAHL, Embase, Web of Science, and Scopus) in addition to hand-searching. The search terms included diabetes, adults, cognitive-focused intervention, cognition, self-management, and hemoglobin A1C (HbA1C).

RESULTS

Eleven studies met the inclusion criteria. Cognitive ability and diabetes self-management were assessed using different measurements, and glycemic levels were measured with HbA1C. Nine studies applied cognitive training, one provided working memory training, and one used occupational therapy. Eight studies combined cognitive training with a co-intervention, including self-efficacy, lifestyle management, physical training, chronic disease self-management program, square-stepping exercise, psychoeducational intervention, and empowerment. Eight studies showed statistically significant improvements in at least one cognitive domain.

CONCLUSIONS

Cognitive-focused interventions have a positive effect on improving memory and executive function. However, the evidence of cognitive-focused interventions on diabetes self-management and glycemic levels has not been established. Future studies to improve cognition using effective strategies to improve cognitive function enhancing diabetes self-management behaviors and managing glycemic levels are warranted.

Evaluating the influence of altered cerebral hemodynamics on cognitive performance in asymptomatic carotid artery stenosis: A systematic review

OBJECTIVE

Substantial controversy exists regarding asymptomatic carotid stenosis (ACS) and its potential role in the pathophysiology of cognitive impairment. If proven, this hypothesis may suggest an additional definition for symptomatic carotid disease that would alter current management. This study aimed to synthesize the literature evaluating the relationship between impaired cerebral hemodynamics and cognition in patients with ACS.

METHODS

A literature search was performed using MEDLINE, Embase, and EBM Reviews through May 2022. We included prospective case-control studies that used validated, objective measure(s) of either global cognition or one or more domains of cognitive function and assessed cerebrovascular reserve (CVR).

RESULTS

Five studies were included, comprising a total of 782 patients with moderate (50%-69%) to severe (70%-99%) ACS. Patients with ACS and impaired ipsilateral CVR demonstrated significant cognitive impairment compared with controls. Patients with unilateral or bilateral ACS and normal CVR had cognitive scores similar to controls. Those with bilateral CVR impairment demonstrated the lowest cognitive scores.

CONCLUSIONS

This review lends support to the claim that cognitive impairment, likely the result of impaired cerebral hemodynamics, is an under-recognized morbidity in patients with ACS. CVR may serve as an additional tool to determine whether patients are in fact symptomatic from their carotid stenosis and warrant consideration for intervention.

Association of Cognitive Impairment With Chronic Viral Hepatitis Among Older Adults in Taiwan

OBJECTIVE

To evaluate the risk of cognitive impairment among patients with chronic viral hepatitis.

DESIGN

A cross-sectional study.

SETTING

Population-based.

PARTICIPANTS

Individuals 60 years or older were enrolled from the Taiwan Biobank database from 2012.

EXPOSURE

Hepatitis B virus and hepatitis C virus infections.

MEASUREMENT

Cognitive impairment was evaluated using the mini-mental state examination (MMSE). Logistic regression models were used to calculate odds ratios and 95% confidence intervals (CIs). The effects of APOE ε4 polymorphisms on the association between viral hepatitis and the risk of cognitive impairment were also investigated.

RESULTS

We recruited 912 participants with cognitive impairment and 22 869 participants without cognitive impairment. The adjusted odds ratio (aOR) for cognitive impairment was 1.38 (95% CI: 1.03-1.85, p = 0.033) among participants with hepatitis C virus infection and 1.14 (95% CI: 0.91-1.43, p = 0.257) among participants with hepatitis B virus infection. Participants with hepatitis C virus infection and without hepatitis B virus infection had a higher risk of cognitive impairment (aOR: 1.52, 95% CI: 1.13-2.04, p = 0.006). The MMSE subcategories most associated with hepatitis C virus infection were orientation and design copying. The association between hepatitis C virus infection and cognitive impairment was higher among participants with ε4 alleles of the APOE gene than among those without alleles (aOR: 2.18, 95% CI: 1.21-3.91, p = 0.009).

CONCLUSIONS

Our findings suggest that individuals 60 years or older with chronic hepatitis C virus infection are at increased risk of cognitive impairment.

Illiterate Addenbrooke's Cognitive Examination-III in Three Indian Languages: An Adaptation and Validation Study

BACKGROUND

Literacy is an important factor that predicts cognitive performance. Existing cognitive screening tools are validated only in educated populations and are not appropriate for older adults with little or no education leading to poor performance on these tests and eventually leading to misdiagnosis. This challenge for clinicians necessitates a screening tool suitable for illiterate or low-literate older individuals.

OBJECTIVES

The objective was to adapt and validate Addenbrooke's Cognitive Examination-III (ACE-III) for screening general cognitive functions in illiterate and low-literate older populations in the Indian context in three languages.

METHOD

The Indian illiterate ACE-III was systematically adapted by modifying the original items of the Indian literate ACE-III to assess the cognitive functions of illiterates and low-literates with the consensus of an expert panel of professionals working in the area of dementia and related disorders. A total of 180 illiterate or low-literate participants (84 healthy-controls, 50 with dementia, and 46 with mild cognitive impairment [MCI]) were recruited from three different centers speaking Bengali, Hindi, and Kannada to validate the adapted version.

RESULTS

The optimal cut-off score for illiterate ACE-III to distinguish controls from dementia in all 3 languages was 75. The optimal cut-off scores in distinguishing between controls and MCI ranged from 79 to 82, with a sensitivity ranging from 93% to 99% and a specificity ranging from 72% to 99%.

CONCLUSION

The test is found to have good psychometric properties and is a reliable cognitive screening tool for identifying dementia and MCI in older adults with low educational backgrounds in the Indian context.

Predicting the incidence of mild cognitive impairment with a computer-based cognitive assessment tool in community-dwelling older adults: The Otassha study

This study examined the ability of a computer-based cognitive assessment tool (CompBased-CAT) to predict mild cognitive impairment (MCI) in community-dwelling older adults. A two-year longitudinal study was conducted using data from 2016 to 2018 from the Otassha study cohort of community-dwelling older adults. MCI was defined as a Mini-Mental Status Examination (MMSE) score of <27. The CompBased-CAT was used at baseline, with each subtest score converted into a Z-score. Subsequently, the total Z-scores were calculated. Participants were divided into robust and MCI groups, and all variables were compared using the t-test or χ2 test. Receiver operating characteristic (ROC) curves and logistic regression analyses were conducted, with MCI and total Z-scores as dependent and independent variables, respectively. Among the 455 participants (median age, 72 years; range, 65-89 years; 282 women and 173 men), 32 developed MCI after two years. The participants in the MCI group were significantly older. They had lower maximal gait speed, baseline MMSE scores, subtest Z-scores, and total Z-scores than those in the robust group. The area under the ROC curve was 0.79 (95% confidence interval: 0.70-0.87; P <0.01). The sensitivity was 0.76, and the specificity was 0.75. The logistic regression analysis showed an odds ratio of 1.34 (95% confidence interval: 1.18-1.52; P <0.01). This study showed that CompBased-CAT can detect MCI, which is an early stage of dementia. Thus, CompBased-CAT can be used in future community health checkups and events for older adults.

Prevalence of Possible Idiopathic Normal Pressure Hydrocephalus in Sweden: A Population-Based MRI Study in 791 70-Year-Old Participants

BACKGROUND AND OBJECTIVES

Very divergent prevalence rates for idiopathic normal pressure hydrocephalus (iNPH) are reported, probably due to differences in study sample selection and diagnostic criteria. This MRI-based study aimed to determine the prevalence of iNPH and iNPH-specific radiologic changes and their association with clinical symptoms in a large, 70-year-old population-based cohort (Gothenburg H70).

METHODS

In this cross-sectional study, disturbances in gait and balance, cognition, and urinary continence were assessed using clinical examination and self-report. MRI was evaluated for iNPH-specific imaging markers. iNPH was diagnosed according to International Guidelines (I.G.). Based on radiologic findings, participants were allocated to 1 of 4 groups: (A) Evans index (EI) ≤0.3 (reference), (B) EI >0.3 without other iNPH-typical radiologic findings, (C) radiologically probable iNPH according to I.G., and (D) radiologically holistically probable (h-probable) iNPH fulfilling radiologic criteria according to I.G. plus highly iNPH-specific changes according to an experienced neuroradiologist.

RESULTS

The Gothenburg H70 Studies include 791 individuals (377 men, 414 women) born in 1944 who underwent brain MRI. The prevalence of iNPH was 1.5% (2.1% for men, 0.96% for women) according to I.G. Ninety participants (11%) had EI >0.3 without other iNPH-typical radiologic findings, 29 (3.7%) fulfilled the I.G. radiologic probable iNPH criteria alone, and 11 (1.4%) were classified as radiologically h-probable iNPH. Forty participants (5.1%) had I.G. radiologic features of iNPH (70% men vs 30% women, p = 0.005). Gait disturbances were more common in participants with EI >0.3 without other radiologic iNPH features (B) (33%) compared with the reference group (A) (19%) (p = 0.006). All clinical symptoms were more common in participants with I.G. radiologic features of iNPH (C + D) than they were in the reference group (A) (p < 0.03).

DISCUSSION

The iNPH prevalence of 1.5% among 70-year-olds, which is considerably higher than earlier reported in this age group, suggests that iNPH may be more common than previously assumed. This is supported by the 5.1% total prevalence of imaging signs of iNPH. Ventriculomegaly without other iNPH-typical radiologic findings may be an early sign of developing iNPH in some patients.

Aortic Characteristic Impedance and Suspected Mild Cognitive Impairment in a Community-Based Healthy Population

BACKGROUND

Aging of the proximal aorta can lead to increased pressure and flow pulsatility in the cerebral microcirculation, which may cause cognitive impairment. This study investigated the association between aortic characteristic impedance (Zc), an indicator of regional stiffness of the proximal aorta, and suspected mild cognitive impairment (MCI), compared with carotid-femoral pulse wave velocity (CFPWV).

METHODS AND RESULTS

A total of 1461 healthy community residents (46.4% men; age range, 35-96 years [mean±SD, 59.9±11.8 years]) without a history of cardiovascular events or stroke were included in the study. Zc was estimated using applanation tonometry and echocardiography. Cognitive function was assessed using the Mini-Mental State Examination. Education-adjusted cut points were used to define suspected MCI. Subjects with suspected MCI (n=493 [33.7%]) had significantly higher Zc and CFPWV than those without. In multivariable analysis, both Zc and CFPWV were inversely associated with Mini-Mental State Examination score. Zc (odds ratio per 1 SD, 1.22 [95% CI, 1.09-1.37] and CFPWV (odds ratio per 1 SD, 1.18 [95% CI, 1.01-1.38]) was also significantly associated with suspected MCI, after adjusting for age, sex, education level, mean arterial pressure, hypertension, diabetes, low-density lipoprotein cholesterol, and smoking status. In joint analysis, Zc was significantly associated with suspected MCI, but CFPWV was not. In the age subgroups of <50 years and 50 to 70 years, only Zc was significantly associated with suspected MCI.

CONCLUSIONS

This study found that Zc was significantly associated with Mini-Mental State Examination score and suspected MCI, especially in younger and middle-aged adults. These findings suggest that Zc may be a useful biomarker for identifying individuals at risk for MCI.

Natural language processing techniques for studying language in pathological ageing: A scoping review

BACKGROUND

In the past few years there has been a growing interest in the employment of verbal productions as digital biomarkers, namely objective, quantifiable behavioural data that can be collected and measured by means of digital devices, allowing for a low-cost pathology detection, classification and monitoring. Numerous research papers have been published on the automatic detection of subtle verbal alteration, starting from written texts, raw speech recordings and transcripts, and such linguistic analysis has been singled out as a cost-effective method for diagnosing dementia and other medical conditions common among elderly patients (e.g., cognitive dysfunctions associated with metabolic disorders, dysarthria).

AIMS

To provide a critical appraisal and synthesis of evidence concerning the application of natural language processing (NLP) techniques for clinical purposes in the geriatric population. In particular, we discuss the state of the art on studying language in healthy and pathological ageing, focusing on the latest research efforts to build non-intrusive language-based tools for the early identification of cognitive frailty due to dementia. We also discuss some challenges and open problems raised by this approach.

METHODS & PROCEDURES

We performed a scoping review to examine emerging evidence about this novel domain. Potentially relevant studies published up to November 2021 were identified from the databases of MEDLINE, Cochrane and Web of Science. We also browsed the proceedings of leading international conferences (e.g., ACL, COLING, Interspeech, LREC) from 2017 to 2021, and checked the reference lists of relevant studies and reviews.

MAIN CONTRIBUTION

The paper provides an introductory, but complete, overview of the application of NLP techniques for studying language disruption due to dementia. We also suggest that this technique can be fruitfully applied to other medical conditions (e.g., cognitive dysfunctions associated with dysarthria, cerebrovascular disease and mood disorders).

CONCLUSIONS & IMPLICATIONS

Despite several critical points need to be addressed by the scientific community, a growing body of empirical evidence shows that NLP techniques can represent a promising tool for studying language changes in pathological aging, with a high potential to lead a significant shift in clinical practice.

WHAT THIS PAPER ADDS

What is already known on this subject Speech and languages abilities change due to non-pathological neurocognitive ageing and neurodegenerative processes. These subtle verbal modifications can be measured through NLP techniques and used as biomarkers for screening/diagnostic purposes in the geriatric population (i.e., digital linguistic biomarkers-DLBs). What this paper adds to existing knowledge The review shows that DLBs can represent a promising clinical tool, with a high potential to spark a major shift to dementia assessment in the elderly. Some challenges and open problems are also discussed. What are the potential or actual clinical implications of this work? This methodological review represents a starting point for clinicians approaching the DLB research field for studying language in healthy and pathological ageing. It summarizes the state of the art and future research directions of this novel approach.

Mapping Cognitive Trajectories and Detecting Early Dementia Using the Mini-Mental State Examination Cognitive Charts: Application to the French Three-City Cohort

The Cognitive Quotient (QuoCo) classification algorithm monitoring decline on age- and education-adjusted Mini-Mental State Examination (MMSE)-derived cognitive charts has proved superior to the conventionally-used cut-off for identifying incident dementia; however, it remains to be tested in different settings. Data were drawn from the Three-City Cohort to 1) assess the screening accuracy of the QuoCo, and 2) compare its performance to that of serial MMSE tests applying different cut-offs. For the QuoCo, sensitivity was 74.2 (95% CI: 71.4-76.8) and specificity 84.1 (83.6-84.7) and for the MMSE < 24, 64.1 (61.1-67.0) and 94.8 (94.4-95.1), respectively; whereas overall accuracy and sensitivity was highest for MMSE cut-offs <25 and <26. User-friendly charts for mapping cognitive trajectories over visits with an alert for potentially 'abnormal' decline can be of practical use and encourage regular monitoring in primary care where the <24 cut-off is still widely used despite its poor sensitivity.

Toward an intelligent computing system for the early diagnosis of Alzheimer's disease based on the modular hybrid growing neural gas

Objective

The proportion of older people will soon include nearly a quarter of the world population. This leads to an increased prevalence of non-communicable diseases such as Alzheimer's disease (AD), a progressive neurodegenerative disorder and the most common dementia. mild cognitive impairment (MCI) can be considered its prodromal stage. The early diagnosis of AD is a huge issue. We face it by solving these classification tasks: MCI-AD and cognitively normal (CN)-MCI-AD.

Methods

An intelligent computing system has been developed and implemented to face both challenges. A non-neural preprocessing module was followed by a processing one based on a hybrid and ontogenetic neural architecture, the modular hybrid growing neural gas (MyGNG). The MyGNG is hierarchically organized, with a growing neural gas (GNG) for clustering followed by a perceptron for labeling. For each task, 495 and 819 patients from the Alzheimer's disease neuroimaging initiative (ADNI) database were used, respectively, each with 211 characteristics.

Results

Encouraging results have been obtained in the MCI-AD classification task, reaching values of area under the curve (AUC) of 0.96 and sensitivity of 0.91, whereas 0.86 and 0.9 in CN-MCI-AD. Furthermore, a comparative study with popular machine learning (ML) models was also performed for each of these tasks.

Conclusions

The MyGNG proved to be a better computational solution than the other ML methods analyzed. Also, it had a similar performance to other deep learning schemes with neuroimaging. Our findings suggest that our proposal may be an interesting computing solution for the early diagnosis of AD.

Application of a Novel Endpoint Staging Framework: Proof of Concept in the AMBAR Study

Background

A theoretical endpoint staging framework was previously developed and published, aligning outcomes (i.e., memory) to the stage of Alzheimer's disease (AD) in which a given outcome is most relevant (i.e., has the greatest risk of degradation). The framework guides the selection of endpoints measuring outcomes relevant within a target AD population. Here, a proof of concept is presented via post-hoc analyses of the Alzheimer Management by Albumin Replacement (AMBAR) Phase 2b clinical trial in patients with AD (NCT01561053, 2012).

Objective

To evaluate whether aligning endpoints measuring cognition, function, and quality of life to hypothesized 'target' stages of AD yields magnitudes of treatment efficacy greater than those reported in the AMBAR full analysis set (FAS).

Methods

Three endpoints were tested: ADAS-Cog 12, ADCS-ADL, and QoL-AD. The magnitude of treatment efficacy was hypothesized to be maximized in the target stages of mild, mild-to-moderate, and very mild AD, respectively, compared to the full analysis set (FAS) and non-target stages.

Results

For ADAS-Cog 12, the magnitude of treatment efficacy was largest in the non-target stage (-4.0, p = 0.0760) compared to target stage and FAS. For ADCS-ADL and QoL-AD, the magnitude of treatment efficacy was largest in the target stage (14.2, p = 0.0003; 2.4, p < 0.0001, respectively) compared to non-target stage and FAS.

Conclusions

Findings indicated that evaluating endpoints in the most relevant AD stage can increase the magnitude of the observed treatment efficacy. Evidence provides preliminary proof of concept for the endpoint staging framework.

APOE Genotype Modifies the Association between Midlife Adherence to the Planetary Healthy Diet and Cognitive Function in Later Life among Chinese Adults in Singapore

BACKGROUND

It remains unclear if adherence to the planetary healthy diet (PHD), designed to improve human and environmental health, is associated with better cognitive function in aging, and if this association differs by apolipoprotein E (APOE) genotype.

OBJECTIVES

We aimed to examine the association between the PHD pattern and risk of poor cognitive function, and to further assess whether the APOE ε4 allele could modify this association.

METHODS

The study included 16,736 participants from the Singapore Chinese Health Study. The PHD score was calculated using data from a validated 165-item food frequency questionnaire at baseline (1993-1998), with higher scores indicating greater adherence to the PHD. Cognitive function was assessed by the Singapore-modified Mini-Mental State Examination at follow-up 3 visits (2014-2016). A subset of 9313 participants had APOE genotype data. Logistic regression models were used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs), with adjustment for potential confounders.

RESULTS

We identified 2397 (14.3%) cases of poor cognitive function. In the total population, OR (95% CI) of poor cognitive function for each one-SD increment in the PHD score was 0.89 (0.85, 0.93). Carriers of APOE ε4 allele had increased risk of poor cognitive function (OR: 1.36, 95% CI: 1.15, 1.61). There was a significant interaction between the PHD score and the APOE ε4 allele (P-interaction = 0.042). Each one-SD increment in the PHD score was significantly associated with lower risk of poor cognitive function (OR: 0.89; 95% CI: 0.83, 0.96) in non-carriers of APOE ε4 allele, but not in APOE ε4 allele carriers (OR: 1.04, 95% CI: 0.89, 1.23).

CONCLUSIONS

Midlife adherence to the PHD was associated with reduced risk of poor cognitive function in later life. However, this was not observed in carriers of APOE ε4 allele who had higher risk of poor cognitive function.

Hypertension & dementia: Pathophysiology & potential utility of antihypertensives in reducing disease burden

Dementia is a common cause of disability and dependency among the elderly due to its progressive neurodegenerative nature. As there is currently no curative therapy, it is of major importance to identify new ways to reduce its prevalence. Hypertension is recognised as a modifiable risk factor for dementia, particularly for the two most common subtypes; vascular dementia (VaD) and Alzheimer's disease (AD). From the current literature, identified through a comprehensive literature search of PubMed and Cochrane Library, this review aims to establish the stage in adulthood when hypertension becomes a risk for cognitive decline and dementia, and whether antihypertensive treatment is effective as a preventative therapy. Observational studies generally found hypertension in mid-life (age 45-64) to be correlated with an increased risk of cognitive decline and dementia incidence, including both VaD and AD. Hypertension manifesting in late life (age ≥ 65) was demonstrated to be less of a risk, to the extent that incidences of high blood pressure (BP) in the very elderly (age ≥ 75) may even be related to reduced incidence of dementias. Despite the evidence linking hypertension to dementia, there were conflicting findings as to whether the use of antihypertensives was beneficial for its prevention and this conflicting evidence and inconsistent results could be due to the methodological differences between the reviewed observational and randomised controlled trials. Furthermore, dihydropyridine calcium channel blockers and potassium-sparing diuretics were proposed to have neuroprotective properties in addition to BP lowering. Overall, if antihypertensives are confirmed to be beneficial by larger-scale homogenous trials with longer follow-up durations, treatment of hypertension, particularly in mid-life, could be an effective strategy to considerably lower the prevalence of dementia. Furthermore, greater clarification of the neuroprotective properties that some antihypertensives possess will allow for better clinical practice guidance on the choice of antihypertensive class for both BP lowering and dementia prevention.

Is vestibular function related to human hippocampal volume?

BACKGROUND

Recent studies implicate the effect of vestibular loss on cognitive decline, including hippocampal volume loss. As hippocampal atrophy is an important biomarker of Alzheimer's disease, exploring vestibular dysfunction as a risk factor for dementia and its role in hippocampal atrophy is of interest.

OBJECTIVE

To replicate previous literature on whole-brain and hippocampal volume in semicircular canal dysfunction (bilateral vestibulopathy; BV) and explore the association between otolith function and hippocampal volume.

METHODS

Hippocampal and whole-brain MRI volumes were compared in adults aged between 55 and 83 years. Participants with BV (n = 16) were compared to controls individually matched on age, sex, and hearing status (n = 16). Otolith influence on hippocampal volume in preserved semicircular canal function was evaluated (n = 34).

RESULTS

Whole-brain and targeted hippocampal approaches using volumetric and surface-based measures yielded no significant differences when comparing BV to controls. Binary support vector machines were unable to classify inner ear health status above chance level. Otolith parameters were not associated with hippocampal volume in preserved semicircular canal function.

CONCLUSIONS

No significant differences in whole-brain or hippocampal volume were found when comparing BV participants with healthy controls. Saccular parameters in subjects with preserved semicircular canal function were not associated with hippocampal volume changes.

Predicting cognitive dysfunction and regional hubs using Braak staging amyloid-beta biomarkers and machine learning

Mild cognitive impairment (MCI) is a transitional stage between normal aging and early Alzheimer's disease (AD). The presence of extracellular amyloid-beta (Aβ) in Braak regions suggests a connection with cognitive dysfunction in MCI/AD. Investigating the multivariate predictive relationships between regional Aβ biomarkers and cognitive function can aid in the early detection and prevention of AD. We introduced machine learning approaches to estimate cognitive dysfunction from regional Aβ biomarkers and identify the Aβ-related dominant brain regions involved with cognitive impairment. We employed Aβ biomarkers and cognitive measurements from the same individuals to train support vector regression (SVR) and artificial neural network (ANN) models and predict cognitive performance solely based on Aβ biomarkers on the test set. To identify Aβ-related dominant brain regions involved in cognitive prediction, we built the local interpretable model-agnostic explanations (LIME) model. We found elevated Aβ in MCI compared to controls and a stronger correlation between Aβ and cognition, particularly in Braak stages III-IV and V-VII (p < 0.05) biomarkers. Both SVR and ANN, especially ANN, showed strong predictive relationships between regional Aβ biomarkers and cognitive impairment (p < 0.05). LIME integrated with ANN showed that the parahippocampal gyrus, inferior temporal gyrus, and hippocampus were the most decisive Braak regions for predicting cognitive decline. Consistent with previous findings, this new approach suggests relationships between Aβ biomarkers and cognitive impairment. The proposed analytical framework can estimate cognitive impairment from Braak staging Aβ biomarkers and delineate the dominant brain regions collectively involved in AD pathophysiology.