Cognitive Dysfunction in Urban-Community Dwelling Prefrail Older Subjects

Relationship between Mild Cognitive Impairment, Pre-Frailty, Physical and Psychological Functioning, and Functional Capacity among Community-Dwelling Older Adults

Mild cognitive impairment (MCI) is associated with a high risk of dementia. Reportedly, 54.6% of older adults with MCI fall into the pre-frailty category. However, it is unclear what differences exist in older adults with regard to their physical, psychological, and functional capacities, which depend on MCI, pre-frailty, or a combination of the two. This study aimed to examine the differences between the association between physical function, psychological function, and functional capacity by examining a combination of MCI and pre-frailty among community-dwelling older Japanese individuals. The participants in the analysis were 236 older people living in the community. They were classified into four groups, as follows: normal, MCI only, pre-frailty only, and pre-frailty/MCI; furthermore, their physical, psychological, and functional capacities were compared. In addition, a multinomial logistic regression analysis was performed using MCI and pre-frailty as dependent variables. No associated factors were identified for MCI only, and a depressive mood was only associated with pre-frailty. When pre-frailty and MCI were combined, knee extension muscle strength, fastest gait speed, the s30 s chair stand test, depressed moods, and the instrumental activities of daily living (IADL) were correlated. Our results suggest that when MCI and pre-frailty are combined, declines in both physical and psychological functions and IADL are likely to occur.

Screening prefrailty in Japanese community-dwelling older adults with daily gait speed and number of steps via tri-axial accelerometers

Prefrailty is an intermediate stage between non-frailty and frailty. It is associated with an increased risk of progression to frailty, which makes it important to screen older adults for prefrailty at an early stage. This study verified whether daily gait speed and number of steps measured using a tri-axial accelerometer could be used to identify prefrailty. In total, 1692 Japanese community-dwelling older adults were divided into robust (n = 1032) and prefrail (n = 660) groups based on the Kihon Checklist, which is a self-administered questionnaire. Both daily gait speed and number of steps were measured for two weeks using tri-axial accelerometers. We also calculated the area under the ROC curve and the cut-off values for these parameters. Our results showed that the cut-off value for daily gait speed was 106.3 cm/s, while that for number of steps was 6342.2. In addition, we found that the combined assessment of both cut-off values was a more effective way to screen older adults with prefrailty status compared to either parameter alone. This is also considered an effective way to reduce national expenditures for daily care assistance.

How gait influences frailty models and health-related outcomes in clinical-based and population-based studies: a systematic review

Aging is often associated with a decline in physical function that eventually leads to loss of autonomy in activities of daily living (ADL). Walking is a very common ADL, important for main determinants of quality of life in older age, and it requires the integration of many physiological systems. Gait speed has been described as the 'sixth vital sign' because it is a core indicator of health and function in aging and disease. We reviewed original studies up to June 2020 that assessed frailty in both longitudinal and cross-sectional observational studies, paying particular attention to how gait is measured in older population and how the gait parameter adopted may influence the estimated frailty models and the health-related outcomes of the various studies (i.e. clinical, cognitive, physical, and nutritional outcomes). Eighty-five studies met the search strategy and were included in the present systematic review. According to the frailty tools, more than 60% of the studies used the physical phenotype model proposed by Fried and colleagues, while one-third referred to multi-domain indexes or models and only 5% referred to other single-domain frailty models (social or cognitive). The great heterogeneity observed in gait measurements and protocols limited the possibility to directly compare the results of the studies and it could represent an important issue causing variability in the different outcome measures in both clinical-and population-based settings. Gait appeared to be an indicator of health and function also in frail older adults, and different gait parameters appeared to predict adverse health-related outcomes in clinical, cognitive, and physical domains and, to a lesser extent, in nutritional domain. Gait has the potential to elucidate the common basic mechanisms of cognitive and motor decline. Advances in technology may extend the validity of gait in different clinical settings also in frail older adults, and technology-based assessment should be encouraged. Combining various gait parameters may enhance frailty prediction and classification of different frailty phenotypes.

Potentially modifiable risk factors for slow gait in community-dwelling older adults: A systematic review

PURPOSE

Slow gait speed in older adults is associated with increased risk for falls and fractures, functional dependence, multimorbidity, and even mortality. The risk of these adverse outcomes can be reduced by intervening on potentially modifiable risk factors. The purpose of this systematic review was to identify potentially modifiable risk factors associated with slow gait speed and clinically meaningful gait speed decline in older community-dwelling adults.

METHODS

Literature searches were conducted in MEDLINE, EMBASE, and CINAHL, Google Scholar, and in the bibliographies of retrieved articles.

RESULTS

Forty studies met the inclusion criteria for qualitative review. Study designs were cross-sectional and longitudinal. Operational definitions of 'slow gait' and 'meaningful gait speed decline' were variable and based on sample distributions (e.g. quartiles), external criteria (e.g. < 0.8 m/s), and dynamic changes over time (e.g. ≥ 0.05 m/s decline per year). Twenty-six potentially modifiable risk factors were assessed in at least two studies. The risk factors most commonly investigated and that showed significant associations with slow gait and/or meaningful gait speed decline include physical activity, education, body mass index-obesity, pain, and depression/depressive symptoms.

CONCLUSION

Our results suggest that there are modifiable targets to maintain gait speed that are amenable to potential treatment.

Clinical and Neuropsychological Correlates of Prefrailty Syndrome

Physical frailty is closely associated with cognitive impairment. We aim to investigate the neuropsychological profiles of prefrail and non-frail dementia-free community-dwelling older adults using a comprehensive neuropsychological evaluation, and to examine the association between specific frailty criteria and clinical and neuropsychological scores. Participants completed a comprehensive standardized neuropsychological evaluation (covering cognitive domains such as memory, executive functions, language and attention), and frailty assessment. Frailty was assessed according to biological criteria: unintentional weight loss, exhaustion, low physical activity, slowness, and weakness. The sample comprised 60 dementia-free community-dwelling adults, aged 65 years or older (range 65-89 years; 60.0% women). Forty-two participants were classified as robust (no frailty criteria present), and 18 as prefrail (1 or 2 frailty criteria present). We explored neurocognitive differences between the groups and examined the association between specific criteria of frailty phenotype and clinical and neuropsychological outcomes with bivariate tests and multivariate models. Prefrail participants showed poorer cognitive performance than non-frail participants in both memory and non-memory cognitive domains. However, delayed episodic memory was the only cognitive subdomain that remained significant after controlling for age, gender, and educational level. Gait speed was significantly associated with general cognitive performance, immediate memory, and processing speed, while grip strength was associated with visual episodic memory and visuoconstructive abilities. Both gait speed and grip strength were negatively associated with depressive scores. Our results suggest that prefrailty is associated with cognitive dysfunction. The fact that specific cognitive domains may be susceptible to subclinical states of physical frailty may have important clinical implications. Indeed, early detection of specific cognitive dysfunctions may allow opportunities for reversibility.

Effect of various exercises on frailty among older adults with subjective cognitive concerns: a randomised controlled trial

BACKGROUND

Physical exercise has been linked to reduced frailty, but there is insufficient evidence of beneficial effects in community-dwelling older adults with subjective cognitive concerns.

OBJECTIVE

This study aimed to clarify the effects of physical exercise in this population.

DESIGN

Single-blind randomised controlled trial.

SETTING

Community sports centres.

PARTICIPANTS

Residents aged 65-85 years were screened using the Kihon checklist; those with subjective cognitive concerns were invited for eligibility assessment. In total, 415 community-dwelling older adults were enrolled and randomised.

METHODS

This trial investigated the effects of aerobic training (AT), resistance training (RT) and combined training (AT+RT) programs on reducing frailty. All participants were randomised into one of the three intervention groups or the control group. Participants in the intervention groups underwent a group training program and self-paced home training for 26 weeks. The control group received lectures about health promotion. A 95-item frailty index (FI) was utilised to determine the effects of training. Participants were followed up at weeks 26 and 52.

RESULTS

At baseline, mean age of all participants (47% women) was 72.3 ± 4.6 years, with a mean FI score of 0.3 ± 0.1. Compared with control group, AT improved total FI by 0.020 (CI -0.039 to -0.001, effect size -0.275) and the depression and anxiety component of FI by 0.051 (CI -0.084 to -0.018, effect size -0.469) at week 26, but the effects waned at week 52. No significant differences in FI were found in RT and AT+RT groups at weeks 26 and 52.

CONCLUSIONS

A 26-week AT reduced frailty modestly, especially in the depression and anxiety component, in older adults with subjective cognitive concerns.

Effect of oral health intervention on cognitive decline in community-dwelling older adults: A randomized controlled trial

PURPOSE

The incidence of dementia is rapidly increasing worldwide, especially in developed countries. Little is known regarding the effectiveness of dental intervention to prevent dementia or a decline in cognitive functions among community-dwelling older adults, but a few studies have reported a correlation between the lack of regular dental checkups and dementia. For that reason, this study aimed to investigate the effects of oral health intervention on cognitive functions in community-dwelling subjects with a mild cognitive decline via a randomized controlled trial.

PATIENTS AND METHODS

Fifty-five community-dwelling older adults with a Mini-Mental State Examination score of ≥21 to ≤26 who had not visited a dental clinic in the previous year were randomized to an intervention group (n = 28) or a control group (n = 29). The intervention group received monthly oral health intervention by dental hygienists for 8 months while the control group did not. Data on demographics, cognitive function and oral parameters were collected before and after the intervention.

RESULTS

Twenty-five subjects in the intervention group (mean age 77.0 years) and 25 in the control group (mean age 72.8 years) completed the study. Significant improvements were observed in the Trail Making Test (TMT)-A, TMT-B, bleeding on probing rate, oral diadochokinesis, tongue pressure and chewing ability in the intervention group (P < 0.05). There were also significant interactions between the TMT-A and TMT-B scores, oral diadochokinesis, tongue pressure and chewing ability (P < 0.05).

CONCLUSION

Oral health intervention by dental hygienists may be effective for improving the oral health and executive function of cognitive function assessed via TMT.

The prevalence of cognitive frailty and pre-frailty among older people in Bangkok metropolitan area: a multicenter study of hospital-based outpatient clinics

Objectives:

To identify the prevalence of, and factors associated with, cognitive frailty and prefrailty, and to investigate correlation between frailty tools.

Methods:

One hundred and ninety five older adults were recruited from the medical outpatient clinics of 3 tertiary hospitals in Bangkok metropolitan region. The data collected were demographic information, lifestyle factors, functional status, mood assessment, and cognitive and frailty assessments. The frailty tools used were Frailty Phenotype and FRAIL scale.

Results:

The prevalence of pre-frailty, frailty, mild cognitive impairment (MCI), cognitive pre-frailty and cognitive frailty was 57.4%, 15.9%, 26.2%, 14.4% and 6.7%, respectively. A multivariate analysis showed that age ≥70 years (OR 5.34; 95% CI 2.06-12.63), and education at primary school or under (OR 4.18; 95% CI 1.61-10.82) were associated with cognitive frailty and cognitive pre-frailty. The correlation between physical frailty rated by the Modified Fried Frailty Phenotype and the FRAIL scale was good (Kappa coefficient = 0.741).

Conclusions:

The prevalence of cognitive frailty is not uncommon which requires screening and interventions. Age and a low educational level were related to cognitive frailty/prefrailty. The FRAIL scale yielded a high correlation with Frailty phenotypes, implying its benefit in routine clinical use in primary care practice, where there is limited time and resources.

Effect of Various Exercises on Intrinsic Capacity in Older Adults With Subjective Cognitive Concerns

OBJECTIVES

Physical activity is associated with improvement in overall health and well-being, but robust evidence with comprehensive assessment of general health is lacking. This study aimed to clarify the effects of physical activity on intrinsic capacity among community-dwelling older adults with subjective memory concerns.

DESIGN

A single-blind randomized controlled trial compared aerobic training (AT), resistance training (RT), and combined training (AT+RT) programs for improving general health evaluated by intrinsic capacity.

SETTING

Toyota, Japan.

PARTICIPANTS

Residents (65-85 years old) who screened positive for subjective memory concerns using the Kihon checklist were invited for eligibility assessment. In total, 415 community-dwelling older adults were enrolled and randomized into the AT, RT, AT+RT, and control groups.

METHODS

Participants in the intervention groups underwent a group training program and self-paced home training for 26 weeks. The control group received lectures about health promotion. Intrinsic capacity (IC), constructed based on locomotion, cognition, psychological function, and vitality domains, was used to assess general health at baseline, week 26, and week 52. Between-group differences were exhibited with Z-score change in individual domain and combination of all domains.

RESULTS

At baseline, mean age of all participants (47% women) was 72.3 ± 4.6 years, with a mean composited IC Z-score of -0.2 ± 0.5. Overall, AT and RT improved composite IC Z-scores by 0.17 (95% confidence interval [CI] 0.03-0.30) and 0.17 (95% CI 0.05-0.28) at week 26, respectively, but the beneficial effects waned at week 52. No significant differences in composite IC Z-scores were found in the AT+RT group at weeks 26 and 52.

CONCLUSIONS AND IMPLICATIONS

Twenty-six-week AT with self-paced home training and RT with self-paced home training improve IC among community-dwelling older adults with subjective memory concerns, but the benefits waned subsequently. It will be required to develop optimal interventions that have a continuous beneficial effect on IC among community-dwelling older adults.

Prefrailty in older adults: A concept analysis

BACKGROUND

The concept of prefrailty lacks clarity. Often, prefrailty is defined in relation to frailty and less often as a distinct concept. Theoretical evidence for prefrailty is minimal unlike frailty, which has been examined for decades although consensus about how to measure frailty has not been achieved.

OBJECTIVE

The aim of this study was to conduct a concept analysis of prefrailty to provide greater understanding of this phenomenon in the context of older adults.

DESIGN

Rodgers and Knafl's evolutionary concept analysis approach.

DATA SOURCES

The literature search for the concept analysis was conducted as follows: three databases (MEDLINE, CINAHL, and Abstracts in Social Gerontology databases) were searched using carefully selected search terms; and grey literature was not included.

REVIEW METHODS

In phase one, we used the search strategy and search terms to narrow the search for relevant articles. We selected articles that met the following inclusion criteria: (1) how prefrailty was conceptualized; (2) how prefrailty was measured; and (3) interventions targeted towards prefrailty. In phase two, we extracted data from included articles. In phase three, we analyzed data using thematic analysis and findings were presented as attributes, antecedents, consequences, and related concepts of prefrailty. One example of prefrailty in older adults was presented to highlight the concept in praxis. In phase four, methodological and substantive area experts reviewed and contributed to discussion and interpretation of findings including disciplinary perspectives of prefrailty.

RESULTS

A total of 41 articles were included for synthesis. The attributes of prefrailty were predisposing in nature, non-specific, multidimensional, and cumulative in effects. Antecedents of prefrailty were categorized into the following domains: sociodemographic characteristics, comorbidity, behaviours, and laboratory/clinical markers. Consequences of prefrailty were separated into two themes: increased risk of adverse outcomes and advancing levels of frailty. Surrogate and related terms (noted in the literature) that had shared attributes with prefrailty were increased vulnerability, transitional stage, dynamic process, progressive process with latent phase, and physical frailty.

CONCLUSIONS

As a result of conducting this concept analysis, we found that prefrailty was defined as a clinically silent process that predisposes individuals to frailty. Prefrailty, as a concept, was derived from the Fried's operational definition for frailty. Attributes, antecedents, consequences, and related terms will help clinicians consider how prefrailty presents in older adults separate from frailty. Further research is needed to build upon our understanding from this concept analysis. Tweetable Abstract: Prefrailty is unclear as a concept - Research on sociodemographic characteristics of older adults living with frailty will help clarify.

Falls in community-dwelling prefrail older adults

Frailty has been established as a risk factor for falls, and prefrailty also seems a risk; however, few studies have focused on the association between falls and each of the five components of frailty proposed by Fried. In the present study, we sought to elucidate the association between prefrailty and falls, and moreover, the association of frailty component with falls. Participants were community-dwelling older people who had cognitive complaints but not dementia (N = 447, male 54.6%). Prefrailty was defined as exhibiting one or two of the five Fried criteria. Frail individuals were excluded. Background characteristics were compared between the prefrail and robust groups, and multiple regression analysis was performed to investigate the associations between fall history within the past year and factors that were significantly different between the groups. We also performed logistic regression analysis with adjustment for age, education and gender to assess associations with frailty components. We found that prefrailty was associated with fall history. Depressed mood was also significantly associated with fall history. Among the five frailty criteria, exhaustion was significantly associated with falls. Prefrailty, especially the criteria of exhaustion, and depressed mood were associated with fall history.

Combined Impact of Physical Frailty and Social Isolation on Rate of Falls in Older Adults

OBJECTIVES

The aim of this study was to examine the impact of the combination of physical frailty and social isolation on falling in community-dwelling older adults.

DESIGN

A cross-sectional study of data obtained at registration in a randomized control trial.

SETTING

Community-based study of participants recruited from Toyota, Japan.

PARTICIPANTS

380 community-dwelling older adults (47.9% women, mean age = 72.3 ± 4.6 years).

MEASUREMENTS

Participants were categorized as non-frail or pre-frail/frail based on the Fried frailty criteria (slowness, weakness, exhaustion, low activity, and weight loss). Social isolation was examined using the Lubben Social Network Scale (LSNS-6), and scores lower than 12 points indicated social isolation. Participants were divided into four groups depending on pre-frail/frail status and social isolation, and experiences of multiple falls over the past year were compared between the groups.

RESULTS

Participants were classified into robust (n = 193), physical frailty (PF; n = 108), social isolation (SI; n = 43), and PF with SI (PF+SI; n = 36) groups. A total of 38 (10.0%) participants reported multiple falls. Logistic regression analysis showed that PF and SI groups were not independently associated with falling (PF: OR 1.64, 95% CI 0.65-4.16, SI: OR 2.25, 95% CI 0.77-6.58), while PF+SI group was significantly associated with falling compared with the robust group (OR 3.06, 95% CI 1.00-9.34, p = 0.049) after controlling for confounding factors.

CONCLUSION

Our findings support the assertion that coexistence with physical frailty and social isolation were associated with falling in the older adults.

Glu-mGluR2/3-ERK Signaling Regulates Apoptosis of Hippocampal Neurons in Diabetic-Depression Model Rats

Objectives

Diabetes mellitus is frequently accompanied by depression (diabetes−depression, DD), and DD patients are at higher risk of diabetes-related disability and mortality than diabetes patients without depression. Hippocampal degeneration is a major pathological feature of DD. Here, we investigated the contribution of the Glu−mGluR2/3−ERK signaling pathway to apoptosis of hippocampal neurons in DD model rats.

Methods

The DD model was established by high-fat diet (HFD) feeding and streptozotocin (STZ) injection followed by chronic unpredictable mild stress (CUMS). Other groups were subjected to HFD + STZ only (diabetes alone) or CUMS only (depression alone). Deficits in hippocampus-dependent memory were assessed in the Morris water maze (MWM), motor activity in the open field test (OFT), and depression-like behavior in the forced swim test (FST). Terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) was used to estimate the rate of hippocampal neuron apoptosis. Hippocampal glutamate (Glu) content was measured by high performance liquid chromatography. Hippocampal expression levels of mGluR2/3, ERK, and the apoptosis effector caspase-3 were estimated by immunohistochemistry and Western blotting.

Results

DD model rats demonstrated more severe depression-like behavior in the FST, greater spatial learning and memory deficits in the MWM, and reduced horizontal and vertical activity in the OFT compared to control, depression alone, and diabetes alone groups. All of these abnormalities were reversed by treatment with the mGluR2/3 antagonist LY341495. The DD group also exhibited greater numbers of TUNEL-positive hippocampal neurons than all other groups, and this increased apoptosis rate was reversed by LY341495. In addition, hippocampal expression levels of caspase-3 and mGluR2/3 were significantly higher, ERK expression was lower, and Glu was elevated in the DD group. The mGluR2//3 antagonist significantly altered all these features of DD.

Conclusions

Comorbid diabetes and depression are associated with enhanced hippocampal neuronal apoptosis and concomitantly greater hippocampal dysfunction. These pathogenic effects are regulated by the Glu−mGluR2/3−ERK signaling pathway.

Cognitive function in Prefrail and frail community-dwelling older adults in China

Background

Physical frailty, characterized by reduced physiologic complexity and ability to cope with stressors, is closely associated with cognitive impairment, which increases the risk of poor clinical outcomes. To better capture the association between frailty and cognitive impairment, a new construct, cognitive frailty, has been proposed. Cognitive frailty is a clinical condition characterized by the simultaneous presence of physical frailty and cognitive impairment. There is little evidence on the relationship between physical frailty and cognition, as well as cognitive frailty, in Chinese older adults. We aimed to elucidate whether physical frailty is associated with cognitive impairment in an older Chinese population.

Methods

Data were obtained from the China Comprehensive Geriatric Assessment Study. The sample comprised 3202 community-dwelling adults, aged 60 years and older, from seven Chinese cities. Physical frailty was assessed using a modified, four-item version of the Fried criteria, according to frailty phenotype. Cognitive function was assessed using the Mini-Mental State Examination (MMSE).

Results

The prevalence of physical frailty, prefrailty, cognitive impairment, and cognitive frailty was 9.9, 33.9, 7.5, and 2.3%, respectively (weighted: 8.8, 33.8, 6.5, and 2.0%). The prevalence of the combination of prefrail/frail and cognitive impairment was 5.1% (weighted 4.5%). Frail participants performed worse on global cognition and all cognitive domains than robust and prefrail participants. The MMSE total score was positively correlated with walking speed and negatively correlated with age and frailty. A multivariate logistic regression revealed that after adjusting for age, gender, education level, living area, and chronic diseases, frailty, exhaustion, slowness, and inactivity were significantly associated with poor global cognition.

Conclusions

The standard prevalence of physical frailty, prefrailty, cognitive impairment, and cognitive frailty in community-dwelling older adults in China was 8.8, 33.8, 6.5, and 2.0%, respectively. Frailty, exhaustion, slowness, and inactivity were significantly associated with poor global cognition.