Neurophysiological and Brain Structural Markers of Cognitive Frailty Differ from Alzheimer's Disease

Prevalence of cognitive frailty and its associated factors in a population of Iranian older adults

BACKGROUND

In recent years cognitive frailty has emerged as an important predictor of adverse health outcomes in older adults. Herein, we aimed to investigate the prevalence and associated factors of cognitive frailty in a population of community-dwelling older adults in Iran.

METHOD

This cross-sectional study was conducted as part of the second cycle of the Amirkola Health and Aging Project (AHAP). Physical frailty and cognitive impairment were evaluated using the FRAIL questionnaire and the mini-mental state examination (MMSE) respectively. Cognitive frailty was defined as co-existence of frailty and cognitive impairment without presence of dementia. Depression and disability were assessed using the Persian version of geriatric depression scale (GDS) and instrumental activities of daily living (IADL) questionnaire.

RESULTS

Overall 1775 individuals (47.1% female) with mean age of 69.7 ± 7.3 years were included in the final analysis. The prevalence of cognitive frailty was 12.0%. The prevalence of cognitive frailty among males and females was 4.3% and 20.7%, respectively. After adjusting for all possible confounders through binary logistic regression analysis, factors such as older age (OR 1.06, CI 1.03-1.09), female gender (OR 2.25, CI 1.42-3.57), illiteracy (OR 3.84, CI 2.03-8.29), more comorbidities (OR 1.21, CI 1.12-1.31), depression (OR 2.01, CI 1.40-2.86), and greater IADL disability (OR 1.68, CI 1.44-3.96), were independently and significantly associated with cognitive frailty.

CONCLUSION

In this population of Iranian older adults, prevalence of cognitive frailty was consistent with its estimated mean global prevalence. Age, gender, illiteracy, comorbidities, depression and IADL disability were associated with cognitive frailty. Further research is required to develop screening tools and prevention strategies.

Risk factors and a nomogram for predicting cognitive frailty in Chinese patients with lung cancer receiving drug therapy: A single-center cross-sectional study

BACKGROUND

To identify independent factors of cognitive frailty (CF) and construct a nomogram to predict cognitive frailty risk in patients with lung cancer receiving drug therapy.

METHODS

In this cross-sectional study, patients with lung cancer undergoing drug therapy from October 2022 to July 2023 were enrolled. The data collected includes general demographic characteristics, clinical data characteristics and assessment of tools for cognitive frailty and other factors. Logistic regression was harnessed to determine the influencing factors, R software was used to establish a nomogram model to predict the risk of cognitive frailty. The enhanced bootstrap method was employed for internal verification of the model. The performance of the nomogram was evaluated by using calibration curves, the area under the receiver operating characteristic curve, and decision curve analysis.

RESULTS

A total of 372 patients were recruited, with a cognitive frailty prevalence of 56.2%. Age, education background, diabetes mellitus, insomnia, sarcopenia, and nutrition status were identified as independent factors. Then, a nomogram model was constructed and patients were classified into high- and low-risk groups with a cutoff value of 0.552. The internal validation results revealed good concordance, calibration and discrimination. The decision curve analysis presented prominent clinical utility.

CONCLUSIONS

The prevalence of cognitive frailty was higher in lung cancer patients receiving drug therapy. The nomogram could identify the risk of cognitive frailty intuitively and simply in patients with lung cancer, so as to provide references for early screening and intervention for cognitive frailty at the early phases of drug treatment.

Demographic and biological factors in interrelationships between physical, cognitive, psychological, and social frailty in community-dwelling older adults: Data from the Birjand Longitudinal Aging Study (BLAS)

Complex interrelationships may exist among different types of frailty. This study aimed to evaluate the demographic and biological factors that influence the different types of frailty in community-dwelling older adults in Iran through a cross-sectional analysis of data obtained from the Birjand Longitudinal Aging Study. This study is an ongoing cohort study of people aged 60 years and over and employed a multistage stratified cluster random sampling. Anthropometric measures were obtained by nurses. The "Fried frailty phenotype" was defined as physical frailty. Cognitive frailty was assessed using the Mini-Mental State Examination. Social frailty was evaluated by some questions, and psychological frailty was assessed using a patient health questionnaire. Blood samples were taken after overnight fasting. All statistical analyses were performed using Stata12 (Texas, USA) and Python. Some type of frailty had been experienced by 62.27 % of the older adults. Cognitive frailty was the dominant type of frailty (55.69 %). Based on multivariate regression analysis, age, sex, education, and marital status were the influencing factors in all types of frailty. Network analysis revealed that physical, cognitive, psychological, and social frailty had synergistic effects on each other, and age and sex had dominant interactions with frailty types. Cognitive frailty was dominant compared with other types of frailty, indicating the need to detect cognitive frailty at the earliest stage and to implement an appropriate program to manage cognitive frailty in older adults.

Comparison of various exercise interventions on cognitive function in Alzheimer's patients: A network meta-analysis

OBJECTIVE

Exercise helps enhance cognitive function in Alzheimer's patients, although the most effective forms of exercise remain unknown.

METHODS

This network meta-analysis was registered in INPLASY (INPLASY202330066). According to predetermined criteria, this investigation comprised randomized controlled studies involving exercise therapies in people with Alzheimer's disease. The exercise intervention was ranked using surface under the cumulative ranking curve (SUCRA) and mean ranking, with the critical goal outcomes being overall cognition, executive function, and memory function.

RESULTS

Resistance exercise is the most likely strategy to be beneficial for slowing down overall cognitive function loss in Alzheimer's patients (72.4%). Additionally, multi-component exercise was the most effective way to improve executive function (30.4%). The only type of exercise that significantly affects memory function is resistance exercise. Memory is the cognitive function that is least responsive to exercise.

CONCLUSION

Resistance exercise may be an efficient intervention for overall cognitive function decline in patients with Alzheimer's and conjointly for their memory function. Multi-component exercise is more effective in improving executive function in patients with Alzheimer's disease.

Remediation of cognitive and motor functions in Tunisian elderly patients with mild Alzheimer's disease: implications of music therapy and/or physical rehabilitation

The purpose of this study was to compare the effects of music therapy (MT) and/or physical rehabilitation (PR) on cognitive and motor function in elderly Tunisian male and female patients with mild Alzheimer's disease (AD). Male patients (N: 16; age: 74.19 ± 4.27 years; weight: 76.71 ± 5.22 kg) and female patients (N: 12; age: 71.46 ± 3.36 years; weight: 67.47 ± 4.31 kg) with mild AD were randomly assigned into 4 groups including control group (Co), PR group participated in physical rehabilitation, MT group received music therapy and MT + PR received both music therapy and physical rehabilitation. Participants were required to engage in the study for four months with three 60-min sessions per week. We found all scores of cognitive (MMSE, ADAS-Cog Total and the ADAS-Cog Memory subscale) and motor functions (step length, walking speed, 6MVT and BBS score) evaluated were the greatest in MT + PR compared to the other groups. Our study also demonstrated that MT has a greater effect on cognitive function, while PR has a more pronounced effect on motor function. Changes in MMSE scores were significantly positively correlated in the PR, MT and MT + PR groups with improvements in all motor functions including step length (r = 0.77), walking speed (r = 0.73), 6MVT (r = 0.75) and BBS scores (r = 0.78) in AD patients. In conclusion, the combination of MT and PR seems to be an appropriate intervention approach that needs consideration as a treatment strategy for elderly male and female patients with mild AD.

Risk Factors of Progression to Cognitive Frailty: Singapore Longitudinal Ageing Study 2

INTRODUCTION

Cognitive frailty is associated with higher risk of dementia and adverse health outcomes. However, multidimensional factors that influence cognitive frailty transitions are not known. We aimed to investigate risk factors of incident cognitive frailty.

METHODS

Prospective cohort study participants were community-dwelling adults without dementia and other degenerative disorders and baseline and follow-up, including N = 1,054 participants aged ≥55 free of cognitive frailty at baseline, with complete baseline (March 6, 2009, to June 11, 2013) and follow-up data at 3-5 years later (January 16, 2013, to August 24, 2018). Incident cognitive frailty was defined by one or more criteria of the physical frailty phenotype and <26 of Mini-Mental State Examination (MMSE) score. Potential risk factors assessed at baseline included demographic, socioeconomic, medical, psychological and social factors, and biochemical markers. Data were analyzed using least absolute shrinkage selection operator (LASSO) multivariable logistic regression models.

RESULTS

A total of 51 (4.8%) participants, including 21 (3.5%) of the cognitively normal and physically robust participants, 20 (4.7%) of the prefrail/frail only, and 10 (45.4%) of cognitively impaired only, transited to cognitive frailty at follow-up. Risk factors for transition to cognitive frailty were having eye problem (OR = 2.6, 95% CI 1.24-5.43) and low HDL cholesterol (OR = 4.1, 95% CI 2.03-8.40), while protective factors for cognitive frailty transition were higher levels of education (OR = 0.3, 95% CI 0.10-0.74) and participation in cognitive stimulating activities (OR = 0.4, 95% CI 0.17-0.82).

CONCLUSION

Multi-domain modifiable factors especially related to leisure activities predict cognitive frailty transition and may be targeted for prevention of dementia and associated adverse health outcomes.

Association of age-related eye diseases with cognitive frailty in older adults: a population-based study

BACKGROUND

Age-related eye diseases and cognitive frailty (CF) are both important predictors of adverse health outcomes in older adults, however, little is known about their association.

AIMS

To demonstrate the association between age-related eye diseases and cognitive frailty in a population of Iranian older adults.

METHODS

In this cross-sectional, population-based study, we included 1136 individuals (female n = 514) aged 60 years and older (mean 68.8 ± 6.7 years) who participated in the second cycle of the Amirkola Health and Aging Project (AHAP) between 2016 and 2017. Cognitive function and frailty were evaluated based on Mini-Mental State Examination (MMSE) and the FRAIL scale respectively. Cognitive frailty was defined as coexistence of cognitive impairment (CI) and physical frailty (PF), excluding confirmed cases of dementia such as Alzheimer's disease. Cataract, diabetic retinopathy (DR), age-related macular degeneration (AMD), elevated intraocular pressure (IOP ≥ 21 mmHg) and glaucoma suspects (vertical cup to disc ratio (VCDR) ≥ 0.6) were diagnosed based on standardized grading protocols. Associations between eye diseases and cognitive frailty were evaluated through binary logistic regression analysis.

RESULTS

Overall, CI, PF and CF were observed in 257 (22.6%), 319 (28.1%) and 114 (10.0%) participants respectively. After adjusting for confounders and ophthalmic conditions, individuals with cataract were more likely to have CF (OR 1.66; p-value 0.043), while DR, AMD, elevated IOP and glaucoma suspects (OR 1.32, 1.62, 1.42, 1.36, respectively) were not significantly associated with CF. Furthermore, cataract was significantly associated with CI (OR 1.50; p-value 0.022), but not with frailty (OR 1.18; p-value 0.313).

CONCLUSION

Older adults with cataract were more likely to have cognitive frailty and cognitive impairment. This association demonstrates the implications of age-related eye diseases beyond ophthalmology and substantiates the need for further research involving cognitive frailty in the context of eye diseases and visual impairment.

Brain connectivity in frailty: Insights from The Irish Longitudinal Study on Ageing (TILDA)

Frailty in older adults is associated with greater risk of cognitive decline. Brain connectivity insights could help understand the association, but studies are lacking. We applied connectome-based predictive modeling to a 32-item self-reported Frailty Index (FI) using resting state functional MRI data from The Irish Longitudinal Study on Ageing. A total of 347 participants were included (48.9% male, mean age 68.2 years). From connectome-based predictive modeling, we obtained 204 edges that positively correlated with the FI and composed the "frailty network" characterised by connectivity of the visual network (right); and 188 edges that negatively correlated with the FI and formed the "robustness network" characterized by connectivity in the basal ganglia. Both networks' highest degree node was the caudate but with different patterns: from caudate to visual network in the frailty network; and to default mode network in the robustness network. The FI was correlated with walking speed but not with metrics of global cognition, reinforcing the matching between the FI and the brain connectivity pattern found (main predicted connectivity in basal ganglia).

Medial temporal lobe structure, mnemonic and perceptual discrimination in healthy older adults and those at risk for mild cognitive impairment

Cognitive tests sensitive to the integrity of the medial temporal lobe (MTL), such as mnemonic discrimination of perceptually similar stimuli, may be useful early markers of risk for cognitive decline in older populations. Perceptual discrimination of stimuli with overlapping features also relies on MTL but remains relatively unexplored in this context. We assessed mnemonic discrimination in two test formats (Forced Choice, Yes/No) and perceptual discrimination of objects and scenes in 111 community-dwelling older adults at different risk status for cognitive impairment based on neuropsychological screening. We also investigated associations between performance and MTL sub-region volume and thickness. The at-risk group exhibited reduced entorhinal thickness and impaired perceptual and mnemonic discrimination. Perceptual discrimination impairment partially explained group differences in mnemonic discrimination and correlated with entorhinal thickness. Executive dysfunction accounted for Yes/No deficits in at-risk adults, demonstrating the importance of test format for the interpretation of memory decline. These results suggest that perceptual discrimination tasks may be useful tools for detecting incipient cognitive impairment related to reduced MTL integrity in nonclinical populations.

Predictors of incident reversible and potentially reversible cognitive frailty among Taiwanese older adults

BACKGROUND

Few studies emphasize on predictors of incident cognitive frailty (CF) and examine relationships between various gait characteristics and CF. Therefore, we conducted a 2-year prospective study to investigate potential predictors, including gait characteristics, of incident reversible CF (RCF) and potentially RCF (PRCF) among Taiwanese older adults.

METHODS

Eligible participants were individuals aged ≥ 65 years, who could ambulate independently, and did not have RCF/PRCF at the baseline. The baseline assessment collected information on physical frailty and cognitive measures, in addition to sociodemographic and lifestyle characteristics, preexisting comorbidities and medications, gait characteristics, Tinetti's balance, balance confidence as assessed by Activities-specific Balance Confidence (ABC) scale, and the depressive status as assessed by the Geriatric Depression Scale. The Mini-Mental State Examination (MMSE), Mattis Dementia Rating Scale, and Digit Symbol Substitution Test were used to evaluate cognitive functions. Incident RCF and PRCF were ascertained at a 2-year follow-up assessment.

RESULTS

Results of the multinomial logistic regression analysis showed that incident RCF was significantly associated with older age (odds ratio [OR] = 1.05) and lower ABC scores (OR = 0.97). Furthermore, incident PRCF was significantly associated with older age (OR = 1.07), lower ABC scores (OR = 0.96), the presence of depression (OR = 3.61), lower MMSE scores (OR = 0.83), slower gait velocity (OR = 0.97), and greater double-support time variability (OR = 1.09).

CONCLUSIONS

Incident RCF was independently associated with older age and lower balance confidence while incident PRCF independently associated with older age, reduced global cognition, the presence of depression, slower gait velocity, and greater double-support time variability. Balance confidence was the only modifiable factor associated with both incident RCF and PRCF.

Treatment of Alzheimer's disease by combination of acupuncture and Chinese medicine based on pathophysiological mechanism: A review

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by neurodegeneration, nerve loss, neurofibrillary tangles, and Aβ plaques. In modern medical science, there has been a serious obstacle to the effective treatment of AD. At present, there is no clinically proven and effective western medicine treatment for AD. The reason is that the etiology of AD is not yet fully understood. In 2018, the international community put forward a purely biological definition of AD, but soon this view of biomarkers was widely questioned, because the so-called AD biomarkers are shared with other neurological diseases, the diagnostic accuracy is low, and they face various challenges in the process of clinical diagnosis and treatment. Nowadays, scholars increasingly regard AD as the result of multimechanism and multicenter interaction. Because there is no exact Western medicine treatment for AD, the times call for the comprehensive treatment of AD in traditional Chinese medicine (TCM). AD belongs to the category of "dull disease" in TCM. For thousands of years, TCM has accumulated a lot of relevant treatment experience in the process of diagnosis and treatment. TCM, acupuncture, and the combination of acupuncture and medicine all play an important role in the treatment of AD. Based on the research progress of modern medicine on the pathophysiology of AD, this paper discusses the treatment of this disease with the combination of acupuncture and medicine.

The neurophysiological effect of NMDA-R antagonism of frontotemporal lobar degeneration is conditional on individual GABA concentration

There is a pressing need to accelerate therapeutic strategies against the syndromes caused by frontotemporal lobar degeneration, including symptomatic treatments. One approach is for experimental medicine, coupling neurophysiological studies of the mechanisms of disease with pharmacological interventions aimed at restoring neurochemical deficits. Here we consider the role of glutamatergic deficits and their potential as targets for treatment. We performed a double-blind placebo-controlled crossover pharmaco-magnetoencephalography study in 20 people with symptomatic frontotemporal lobar degeneration (10 behavioural variant frontotemporal dementia, 10 progressive supranuclear palsy) and 19 healthy age- and gender-matched controls. Both magnetoencephalography sessions recorded a roving auditory oddball paradigm: on placebo or following 10 mg memantine, an uncompetitive NMDA-receptor antagonist. Ultra-high-field magnetic resonance spectroscopy confirmed lower concentrations of GABA in the right inferior frontal gyrus of people with frontotemporal lobar degeneration. While memantine showed a subtle effect on early-auditory processing in patients, there was no significant main effect of memantine on the magnitude of the mismatch negativity (MMN) response in the right frontotemporal cortex in patients or controls. However, the change in the right auditory cortex MMN response to memantine (vs. placebo) in patients correlated with individuals' prefrontal GABA concentration. There was no moderating effect of glutamate concentration or cortical atrophy. This proof-of-concept study demonstrates the potential for baseline dependency in the pharmacological restoration of neurotransmitter deficits to influence cognitive neurophysiology in neurodegenerative disease. With changes to multiple neurotransmitters in frontotemporal lobar degeneration, we suggest that individuals' balance of excitation and inhibition may determine drug efficacy, with implications for drug selection and patient stratification in future clinical trials.