Long-term Associations Between Physical Frailty and Performance in Specific Cognitive Domains

Frailty and Processing Speed Performance at the Cusp of Midlife in CATSLife

OBJECTIVES

Frailty is not an end state of aging, but rather represents physiological vulnerability across multiple systems that unfolds across adulthood. However, examinations of frailty at the midlife transition, and how frailty may impact other age-sensitive traits, such as processing speed (PS), remain scarce. Our research aims were to examine frailty and frailty-speed associations before midlife, a ripe developmental period for healthy aging interventions.

METHODS

Using data from the Colorado Adoption/Twin Study of Lifespan behavioral development and cognitive aging (N = 1,215; Mage = 33.23 years; standard deviation = 4.98), we constructed 25-item (FI25) and 30-item (FI30) frailty indices. PS was measured using the Colorado Perceptual Speed task and WAIS-III Digit Symbol (DS) subtest. Multilevel models accounted for clustering among siblings and adjusted for sex, race, ethnicity, adoption status, educational attainment, and age.

RESULTS

Reliability of FI measures was apparent from strong intraclass correlations (ICCs) among identical twin siblings, although ICC patterns across all siblings suggested that FI variability may include nonadditive genetic contributions. Higher FI was associated with poorer PS performance but was significant for DS only (BFI25 = -1.17, p = .001, d = -0.12; BFI30 = -1.21, p = .001, d = -0.12). Furthermore, the negative frailty-DS association was moderated by age (BFI25×age = -0.14, p = .042; BFI30×age=-0.19, p = .008) where increasingly worse performance with higher frailty emerged at older ages.

DISCUSSION

Frailty is evident before midlife and associated with poorer PS, an association that magnifies with age. These findings help elucidate the interrelationship between indicators of frailty and cognitive performance for adults approaching midlife, an understudied period within life-span development.

The key role of depression and supramarginal gyrus in frailty: a cross-sectional study

Background

The age-related decrease in reserve and resistance to stressors is recognized as frailty, one of the most significant challenges identified in recent years. Despite a well-acknowledged association of frailty with cognitive impairment, depression, and gray matter morphology, no clear data are available regarding the nature of this relationship. This cross-sectional study aims to disentangle the role of the behavioral, neuropsychological, and neural components as predictors or moderators of frailty.

Methods

Ninety-six older adults (mean age = 75.49 ± 6.62) were consecutively enrolled and underwent a clinical and MRI (3 T) evaluation to assess frailty, physical activity, global cognitive level, depression, wellbeing, autonomy in daily living, cortical thickness, and subcortical volumes.

Results

Results showed a full mediation of depression on the link between cortical thickness and frailty, while the cognitive level showed no significant mediating role. In particular, left supramarginal thickness had a predicting role on depression, that in turn impacted frailty occurrence. Finally, handgrip weakness was an early key indicator of frailty in this study's cohort.

Conclusion

These data substantiate the role of depression in mediating the link between neural integrity of the supramarginal gyrus and frailty. In the complexity of frailty, handgrip weakness seems to be an early key indicator. These results are relevant for the design of rehabilitation interventions aimed at reversing the frail condition.

Navigating and diagnosing cognitive frailty in research and clinical domains

While physical frailty has been recognized as a clinical entity for some time, the concept of cognitive frailty (CF) is now gaining increasing attention in the geriatrics research community. CF refers to the co-occurrence of physical frailty and cognitive impairment in older adults, which has been suggested as a potential precursor to both dementia and adverse physical outcomes. However, this condition represents a challenge for researchers and clinicians, as there remains a lack of consensus regarding the definition and diagnostic criteria for CF, which has limited its utility. Here, using insights from both the physical frailty literature and cognitive science research, we describe emerging research on CF. We highlight areas of agreement as well as areas of confusion and remaining knowledge gaps, and provide our perspective on fine-tuning the current construct, aiming to stimulate further discussion in this developing field.

Sustaining an ageing population: the role of micronutrients in frailty and cognitive impairment

Age-related frailty and cognitive decline are complex multidimensional conditions that significantly impact the ability of older adults to sustain functional capacity and independence. While underlying causes remain poorly understood, nutrition continually emerges as one associated risk element. Many studies have addressed the importance of adequate nutrition in delaying the onset of these conditions, but the specific role of micronutrients is not well established. The consideration of pre-frailty as an outcome variable is also limited in the current literature. In this review, we focus on the potential value of maintaining micronutrient sufficiency to sustaining the health of the ageing population. Using data from the Irish longitudinal study on ageing, we consider several vitamins known to have a high prevalence of low status in older adults and their impact on pre-frailty, frailty and cognitive impairment. They include vitamin B12 and folate, both of which are associated with multiple biological mechanisms involved in long-term health, in particular in cognitive function; vitamin D, which has been associated with increased risk of musculoskeletal disorders, depression and other chronic diseases; and the carotenoids, lutein and zeaxanthin, that may help mitigate the risk of frailty and cognitive decline via their antioxidant and anti-inflammatory properties. We show that low concentrations of folate and carotenoids are implicated in poorer cognitive health and that the co-occurrence of multiple nutrient deficiencies confers greatest risk for frailty and pre-frailty in the Irish longitudinal study on ageing cohort. These health associations contribute to evidence needed to optimise micronutrient status for health in the older adult population.

Association of kidney function and albuminuria with frailty worsening and death in very old adults

BACKGROUND AND OBJECTIVES

Studies analysing the association of albuminuria and prevalent frailty in community-dwelling very old adults are scarce and lack information on incident frailty. We investigated the association of kidney function decline and increase of albuminuria with frailty worsening or death in very old adults.

DESIGN

Longitudinal analyses with biennial visits of the Berlin Initiative (cohort) Study and a frailty follow-up of 2.1 years.

SETTING/SUBJECTS

1,076 participants with a mean age of 84.3 (5.6) years of whom 54% were female.

METHODS

Partial proportional odds models were used to assess the association of estimated glomerular filtration rate (eGFR) decline and/or albuminuria (albumin creatinine ratio, ACR) with frailty worsening or death.

RESULTS

At frailty baseline, 1,076 participants with an eGFR of 50 (13) ml/min/1.73 m2, 48% being prefrail and 31% frail were included. After median 2.1 years, 960 (90%) participants had valid information on frailty transition: 187 (17.5%) worsened and 111 (10.3%) died. In the multivariable model, the odds of frailty worsening for participants with albuminuria in combination with eGFR <60 ml/min/1.73 m2 were elevated [OR (95% CI): 2.47 (1.41-4.31)] compared to participants without albuminuria and eGFR ≥60 ml/min/1.73 m2 as there was a rapid eGFR decline of ≥3 ml/min/1.73 m2 per year [1.55 (1.04-2.33)] and albuminuria trajectories six years prior [1.53 (1.11-2.10)] to frailty baseline. The odds of death for each exposure were even higher.

CONCLUSIONS

In older adults, advanced stages of CKD and albuminuria alone were associated with 2-fold odds of frailty worsening independent of death.

Association between Perceived Health-Related Quality of Life and Depression with Frailty in the FRASNET Study

Frailty is a major challenge facing the aging world. The phenotype of the frail subject is still far from being satisfactorily defined. We report data on mood, cognition, and quality of life (QoL) in relation to anamnestic factors, health, and socio-economic status in the FRASNET geriatric population (1204 subjects in stable health conditions), which is an observational cohort study that includes fairly balanced groups of Italian frail (421, 35%), pre-frail (449, 37.3%) and robust (334, 27.7%) subjects. A conditional inference tree analysis revealed a substantial influence of psychological variables on frailty. The physical indicator of QoL (Short Form Survey-36-Physical Component Summary, SF-36-PCS) was the predominant variable in the full model (threshold at 39.9, p < 0.001): higher frailty was found in subjects with a caregiver and lower SF-36-PCS. Frailty was also associated with the mental indicator of QoL (Short Form Survey-36-Mental Component Summary, SF-36-MCS), depression (Geriatric Depression Scale, GDS-15), leisure activities, and level of education. In support of the prominent role of inflammation in aging and mental illness, the SF-36-PCS score was correlated with the blood concentration of C-X-C motif chemokine ligand 10 (CXCL10) (r Pearson -0.355, p = 0.015), a critical signal in cell senescence and inflammaging, while the rs7567647 variant in FN1 gene encoding a glycoprotein in the extracellular matrix was significantly associated with frailty in a multivariable model (p = 0.0006). The perception of health-related QoL and subclinical depression contribute to frailty. Their assessment could improve the identification of older patients at increased risk of adverse outcomes.

Mediating effects of cognitive reserve on the relationship between frailty and cognition in older people without dementia

PURPOSE

This study aimed to explore the potential mediating effects of cognitive reserve on the association between frailty and cognition in the older people without dementia.

METHODS

We performed a cross-sectional analysis of data from 3122 community-dwelling older adults (≥ 65-years-old) without dementia of the Cognitive Function and Ageing Study in Wales. A 31-item frailty index was used to assess frailty. A cognitive lifestyle score was constructed to evaluate cognitive reserve, which includes participants' educational level, occupational attainment, and engagement in social and cognitive activities in later life. Linear regression and mediation modeling were used to investigate the relationship between frailty and cognition and the mediating effects of cognitive reserve as well as social and cognitive activities, an alterable component of cognitive reserve for older adults.

RESULTS

Frailty was negatively associated with cognition. Cognitive reserve was a mediator of the association between frailty and global cognition (- 1.92; 95% CI: - 2.50, - 1.35), as well as individual cognitive domains, with indirect effects contributing to 13-59% of the total effects. Social and cognitive activities have smaller but similar mediating effects on these associations.

CONCLUSIONS

Negative effect of frailty on cognition was partially mediated by a reduction in cognitive reserve. Our results support the possibility that enhancing cognitive reserve, especially engagement in social and cognitive activities may protect cognitive health against frailty.

Impact of frailty, mild cognitive impairment and cognitive frailty on adverse health outcomes among community-dwelling older adults: A systematic review and meta-analysis

Aims

This study analyzes the impact of frailty, mild cognitive impairment, and cognitive frailty on adverse outcomes in community-dwelling older adults.

Methods

This systematic review and meta-analysis were conducted using the PRISMA guidelines and MOOSE statement. We developed a specific search strategy for each electronic database and searched PubMed, Web of Science, MEDLINE, and Embase from initial records to July 2021. The studies on adverse outcomes of frailty, pre-frailty, mild cognitive impairment, and mild cognitive impairment with pre-frailty and cognitive frailty were included. Two researchers independently extracted data based on a spreadsheet and assessed the risk of bias. The primary outcomes were mortality, dementia, disability, and hospitalization. The second outcome included quality of life and falls. All analysis was conducted by using Review Manager (RevMan) 5.3 software.

Results

A total of 22 cohort studies (71,544 older adults with mean age ranging from 65.1 to 93.6 years) were included with a low risk of bias and high methodological quality with a NOS score ≥7. Compared to robust elders, individuals identified as frailty were associated with a higher risk of mortality (RR = 2.11, 95% CI: 1.57–2.83) and disability (RR = 5.91, 95% CI: 2.37–14.74). Mild cognitive impairment with pre-frailty was associated with mortality (RR = 1.74, 95% CI: 1.48–2.05) and dementia (RR = 4.15, 95% CI: 1.87–9.20). Pre-frailty was associated with a higher risk of mortality (RR = 1.29, 95% CI: 1.11–1.50). Cognitive frailty was associated with higher risk of incident mortality (RR = 2.41, 95% CI: 1.97–2.94), dementia (RR = 3.67, 95% CI: 2.81–4.78), disability (RR = 11.32, 95% CI: 4.14–30.97), and hospitalization (RR = 2.30, 95% CI: 1.60–3.32), as well as poor quality of life.

Conclusion

Cognitive frailty could be a comprehensive psychosomatic predictor for adverse outcomes among older people. Interactions between frailty, mild cognitive impairment, and cognitive frailty on adverse outcomes must be further explored.

Systematic review registration

[https://inplasy.com/inplasy-2022-5-0064/], identifier [INPLASY202250064].

Specific cognitive domains and frailty trajectories among older Taiwanese adults

Objective: To investigate the associations of specific cognitive functions and with the frailty trajectory among older Taiwanese adults.Methods: At baseline, 730 community-dwelling older adults were recruited from outpatient clinics of a general hospital. Frailty status was defined using phenotype criteria. Global cognition was assessed using the modified Telephone Interview of Cognitive Status and Mini-Mental State Examination (MMSE). The Mattis Dementia Rating Scale (MDRS) and Digit Symbol Substitution Test were used to evaluate 6 cognitive domains: attention, initiation/perseveration, construction, conceptualization, memory, and processing speed. The group-based trajectory model was used to identify latent frailty trajectory groups and the multinomial logistic regression was to examine the relationships of specific cognitive functions with frailty trajectory.Results: Among 485 participants (168 men, 317 women, and mean age: 71.1 ± 5.5 years) completed 2 annual follow-up assessments, three frailty trajectory groups of improvement, no-change, and progression were identified. After adjusting for baseline frailty status, age, sex, global cognition, regular exercise habit, and number of comorbidities, higher scores on MDRS's initiation/perseveration (odds ratio [OR] = 0.85; 95% CI = 0.75-0.95) and attention (OR = 0.63; 95% CI = 0.38-1.00), respectively, were significantly associated with lower risk of frailty progression. Conversely, no significant association was detected between MMSE or TICSM scores and frailty improvement or progression.Conclusion: Specific cognitive functions of initiation/perseveration and attention, rather than global cognition, may be more useful to predict frailty progression, thus allowing the identification of at-risk older adults.

Multi-Concept Frailty Predicts the Late-Life Occurrence of Cognitive Decline or Dementia: An Updated Systematic Review and Meta-Analysis of Longitudinal Studies

Background

Frailty is a multidimensional syndrome that increases an individual’s vulnerability for developing adverse health outcomes, which include dementia. It might serve as a promising target for dementia prevention. However, there are currently no studies summarizing the association between multi-concept frailty and the risk of cognitive disorders. This study aims to summarize the evidence of associations between multi-concept frailty and cognitive disorders based on longitudinal studies.

Methods

Scopus, The Cochrane Library, PsycINFO, CINAHL, PubMed, and EMBASE databases were searched from inception to January 2, 2022. Longitudinal studies, which explored the association of frailty with incident risk of cognitive decline or dementia, were included. The multivariable-adjusted effect estimates were pooled by random-effects models. The evidence credibility was depicted according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) method.

Results

A total of 30 longitudinal studies were included. Four types of frailty concepts were involved, including physical, cognitive, social, and biopsychosocial frailty. The meta-analysis comprised 20 studies of 252,571 older adults (mean age: 64.1–80.4 years), among whom 7,388 participants developed cognitive decline or dementia. Physical frailty was associated with higher risk of developing cognitive disorders [pooled relative risk (pRR) = 1.52, 95% confidence interval (CI): 1.28–1.80, I2 = 21.2%, pRR = 1.62 for cognitive decline, 95% CI: 1.07–2.45, I2 = 40.2%, pRR = 1.37 for all-cause dementia (ACD), 95% CI: 1.13–1.66, I2 = 0.0%]. Cognitive frailty (pRR = 2.90, 95% CI: 1.28–6.55, I2 = 78.1%) and pre-frailty (pRR = 4.24, 95% CI: 2.74–6.56, I2 = 30.2%) were linked to higher risk of ACD. Biopsychosocial frailty could predict a 41% (pRR = 1.41, 95% CI: 1.17–1.71) elevated risk of cognitive decline or dementia [pRR = 1.53 (95% CI: 1.19–1.96) for ACD and 1.11 (95% CI: 1.05–1.17) for Alzheimer’s disease (AD)]. In the systematic review, social frailty was associated with a 53% higher risk of AD. Preventing frailty could avoid a maximum of 9.9% cognitive disorders globally. The overall evidence strength is rated as low-to-moderate. Inconsistency and imprecision are major sources of bias.

Conclusion

Frailty in late life is a promising risk factor for cognitive disorders. Frail elderly should be monitored for their cognitive dynamics and initiate early prevention of dementia.

Systematic Review Registration

www.ClinicalTrials.gov, identifier CRD4202127 3434.

A Longitudinal Study on the Association of Interrelated Factors Among Frailty Dimensions, Cognitive Domains, Cognitive Frailty, and All-Cause Mortality

BACKGROUND

Cognitive frailty integrating impaired cognitive domains and frailty dimensions has not been explored.

OBJECTIVE

This study aimed to explore 1) associations among frailty dimensions and cognitive domains over time and 2) the extended definitions of cognitive frailty for predicting all-cause mortality.

METHODS

This four-year cohort study recruited 521 older adults at baseline (2011-2013). We utilized 1) generalized linear mixed models exploring associations of frailty dimensions (physical dimension: modified from Fried et al.; psychosocial dimension: integrating self-rated health, mood, and social relationship and support; global frailty: combining physical and psychosocial frailty) with cognition (global and domain-specific) over time and 2) time-dependent Cox proportional hazard models assessing associations between extended definitions of cognitive frailty (cognitive domains-frailty dimensions) and all-cause mortality.

RESULTS

At baseline, the prevalence was 3.0%for physical frailty and 37.6%for psychosocial frailty. Greater physical frailty was associated with poor global cognition (adjusted odds ratio = 1.43-3.29, β: -1.07), logical memory (β: -0.14 to -0.10), and executive function (β: -0.51 to -0.12). Greater psychosocial frailty was associated with poor global cognition (β: -0.44) and attention (β: -0.15 to -0.13). Three newly proposed definitions of cognitive frailty, "mild cognitive impairment (MCI)-psychosocial frailty," "MCI-global frailty," and "impaired verbal fluency-global frailty," outperformed traditional cognitive frailty for predicting all-cause mortality (adjusted hazard ratio = 3.49, 6.83, 3.29 versus 4.87; AIC = 224.3, 221.8, 226.1 versus 228.1).

CONCLUSION

Notably, extended definitions of cognitive frailty proposed by this study better predict all-cause mortality in older adults than the traditional definition of cognitive frailty, highlighting the importance of psychosocial frailty to reduce mortality in older adults.

Psychological and Social Factors Associated with Coexisting Frailty and Cognitive Impairment: A Systematic Review

Those living with coexistent frailty and cognitive impairment are at risk of poorer health outcomes. Research often focuses on identifying biological factors. This review sought to identify the association psychological and social factors have with coexisting physical and cognitive decline. Six databases were systematically searched in July 2020. Studies included individuals aged 60 years or older identified as being both frail and cognitively impaired. A narrative synthesis examined patterns within the data. Nine studies were included, most employed a cross-sectional design. Depression was investigated by all nine studies, those with coexistent frailty and cognitive impairment had higher levels of depressive symptoms than peers. Findings were mixed on social factors, although broadly indicate lower education, living alone and lower material wealth were more frequent in those living with coexistent decline. Further research is needed to explore potentially modifiable psychological and social factors which could lead to the development of supportive interventions.

Does the impact of intensive lifestyle intervention on cognitive function vary depending baseline level of frailty? An ancillary study to the Action for Health in Diabetes (Look AHEAD) Trial

AIMS

To assess whether there is an opportune window when intensive lifestyle intervention (ILI) benefits cognitive function.

METHODS

Standardized cognitive assessments were collected following ≥8 years of either ILI or a control condition of diabetes support and education (DSE) in 3708 individuals, ages 45-76 years at enrollment, with type 2 diabetes and overweight or obesity. Frailty index (FI) scores were used to group individuals at baseline into tertiles according to their age-related health status. Linear models were used to describe intervention adherence and cognitive function, with interaction terms to examine the consistency of relationships among tertiles.

RESULTS

Worse baseline FI scores were associated with poorer subsequent performance in tests of attention, processing speed, and executive function. No differences in any measure of cognitive function were observed between intervention groups within any FI tertile (all p > 0.10). Among individuals with worse baseline FI scores, weight gain was associated with poorer global cognitive function among participants assigned to DSE. There was no association between weight changes and cognitive function among participants assigned to ILI.

CONCLUSIONS

Among adults with type 2 diabetes and overweight/obesity, we found no evidence that there is a window of opportunity based on FI when ILI benefits cognitive function.

Portals to frailty? Data-driven analyses detect early frailty profiles

BACKGROUND

Frailty is an aging condition that reflects multisystem decline and an increased risk for adverse outcomes, including differential cognitive decline and impairment. Two prominent approaches for measuring frailty are the frailty phenotype and the frailty index. We explored a complementary data-driven approach for frailty assessment that could detect early frailty profiles (or subtypes) in relatively healthy older adults. Specifically, we tested whether (1) modalities of early frailty profiles could be empirically determined, (2) the extracted profiles were differentially related to longitudinal cognitive decline, and (3) the profile and prediction patterns were robust for males and females.

METHODS

Participants (n = 649; M age = 70.61, range 53-95) were community-dwelling older adults from the Victoria Longitudinal Study who contributed data for baseline multi-morbidity assessment and longitudinal cognitive trajectory analyses. An exploratory factor analysis on 50 multi-morbidity items produced 7 separable health domains. The proportion of deficits in each domain was calculated and used as continuous indicators in a data-driven latent profile analysis (LPA). We subsequently examined how frailty profiles related to the level and rate of change in a latent neurocognitive speed variable.

RESULTS

LPA results distinguished three profiles: not-clinically-frail (NCF; characterized by limited impairment across indicators; 84%), mobility-type frailty (MTF; characterized by impaired mobility function; 9%), and respiratory-type frailty (RTF; characterized by impaired respiratory function; 7%). These profiles showed differential neurocognitive slowing, such that MTF was associated with the steepest decline, followed by RTF, and then NCF. The baseline frailty index scores were the highest for MTF and RTF and increased over time. All observations were robust across sex.

CONCLUSIONS

A data-driven approach to early frailty assessment detected differentiable profiles that may be characterized as morbidity-intensive portals into broader and chronic frailty. Early inventions targeting mobility or respiratory deficits may have positive downstream effects on frailty progression and cognitive decline.

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.

Frailty and cognitive decline

Frailty and cognitive impairment are among the 2 most common geriatric syndromes. Their presence poses major risks to the elderly including greater disability, reduced quality of life, and higher morbi-mortality. Recent evidence suggest that frailty can be a risk factor for incident dementia. The opposite is also true since subjects with Alzheimer's disease and other dementia also present with more severe frailty measures. The mechanisms for the association between frailty and cognitive impairment is not clear, but possibly involves abnormalities in biological processes related to aging. Here, we will review the current evidence of the association between frailty and cognitive impairment. We will also review the possible biological mechanistic links between the 2 conditions. Finally, we will address potential therapeutic targets and interventions that can mitigate both conditions.

Physical frailty and decline in general and specific cognitive abilities: the Lothian Birth Cohort 1936

Background

Physical frailty is associated with many adverse outcomes including disability, chronic disease, hospitalisation, institutionalisation and death. It is unclear what impact it might have on the rate of normal cognitive ageing. We investigated whether physical frailty was related to initial level of, and change in, cognitive abilities from age 70 to 79 years.

Method

Participants were 950 members of the Lothian Birth Cohort 1936. Physical frailty was assessed at age 70 years using the Fried criteria. Cognitive function was assessed at ages 70, 73, 76 and 79 years. We used linear regression to examine cross-sectional and prospective associations between physical frailty status at age 70 years and factor score estimates for baseline level of and change in four cognitive domains (visuospatial ability, memory, processing speed and crystallised ability) and in general cognitive ability.

Results

Physical frailty, but not prefrailty, was associated with lower baseline levels of visuospatial ability, memory, processing speed and general cognitive ability after control for age, sex, education, depressive symptoms, smoking and number of chronic illnesses. Physical frailty was associated with greater decline in each cognitive domain: age-adjusted and sex-adjusted standardised regression coefficients (95% CIs) were: −0.45 (−0.70 to –0.20) for visuospatial ability, −0.32 (−0.56 to –0.07) for memory, −0.47 (−0.72 to −0.22) for processing speed, −0.43 (−0.68 to –0.18) for crystallised ability and −0.45 (−0.70 to –0.21) for general cognitive ability. These associations were only slightly attenuated after additional control for other covariates.

Conclusion

Physical frailty may be an important indicator of age-related decline across multiple cognitive domains.

Frailty effects on non-demented cognitive trajectories are moderated by sex and Alzheimer's genetic risk

BACKGROUND

Age-related frailty reflects cumulative multisystem physiological and health decline. Frailty increases the risk of adverse brain and cognitive outcomes, including differential decline and dementia. In a longitudinal sample of non-demented older adults, we examine whether (a) the level and/or change in frailty predicts trajectories across three cognitive domains (memory, speed, and executive function (EF)) and (b) prediction patterns are modified by sex or Alzheimer's genetic risk (Apolipoprotein E (APOE)).

METHODS

Participants (n = 632; M age = 70.7, range 53-95; 3 waves) were from the Victoria Longitudinal Study. After computing a frailty index, we used latent growth modeling and path analysis to test the frailty effects on level and change in three latent variables of cognition. We tested two potential moderators by stratifying by sex and APOE risk (ε4+, ε4-).

RESULTS

First, frailty levels predicted speed and EF performance (level) and differential memory change slopes. Second, change in frailty predicted the rate of decline for both speed and EF. Third, sex moderation analyses showed that females were selectively sensitive to (a) frailty effects on memory change and (b) frailty change effects on speed change. In contrast, the frailty effects on EF change were stronger in males. Fourth, genetic moderation analyses showed that APOE risk (e4+) carriers were selectively sensitive to frailty effects on memory change.

CONCLUSION

In non-demented older adults, increasing frailty is strongly associated with the differential decline in cognitive trajectories. For example, higher (worse) frailty was associated with more rapid memory decline than was lower (better) frailty. These effects, however, are moderated by both genetic risk and sex.

Integrating Frailty and Cognitive Phenotypes: Why, How, Now What?

PURPOSE OF REVIEW

This review elucidates the concept of frailty in relationship to reserve and resilience, the relationships and shared pathophysiology between physical frailty and cognitive impairment, the theoretical underpinnings of three integrated phenotypes of physical and cognitive impairments, and the potential of incorporating biomarkers into phenotype refinement and validation.

RECENT FINDINGS

The fact that frailty and cognitive impairment are associated and often coexist in older adults has led to the popular view of expanding the definition of frailty to include cognitive impairment. However, there is great variability in approaches to and assumptions regarding the integrated phenotypes of physical frailty and cognitive impairment.

SUMMARY

The development of integrated frailty and cognitive phenotypes should explicate the types of frailty and cognitive impairment they intend to capture and prioritize the incorporation of biological theories that help determine shared and distinct pathways in the progression to physical and cognitive impairments.

Associations between Frailty and Delirium among Older Patients Admitted to an Emergency Department

BACKGROUND

Switzerland's demographic trends show, as elsewhere on the planet, increasing numbers of older and very old adults. This suggests that its healthcare system will suffer serious repercussions, including in the use of care and especially the use of emergency services. Significant numbers of older adults will be at risk of developing multiple chronic conditions including one or more geriatric syndromes, such as frailty and delirium. Few studies to date have documented associations between frailty and delirium.

AIM

To explore the relationships between frailty and delirium in older adult patients consulting (n = 114) at an emergency department (ED) in Switzerland.

METHOD

A cross-sectional study was conducted in a peripheral hospital ED in the French-speaking part of Switzerland. Frailty was assessed using the Tilburg Frailty Indicator (TFI). Delirium was assessed using the Confusion Assessment Method (CAM). Participants' cognitive states were assessed using the 6-item Cognitive Impairment Test (6CIT) and the Informant Questionnaire on Cognitive Decline in the Elderly (IQ-CODE), completed by the participant's most significant informal caregiver.

RESULTS

The mean participant age was 77.6 years (SD = 7.7); the majority of the subjects were women (54%). The participants took an average of 4.7 different medications a day (SD = 3.2, median = 4). More than half (62%) of the participants were frail; 2 and 14% presented signs and symptoms of delirium and subsyndromal delirium, respectively. A weak but significant association between scores for frailty and delirium (p < 0.05) was demonstrated, and clinical observation confirmed this. A 4-h follow-up measurement of delirium in the ED revealed no significant or clinical difference.

CONCLUSION

Although the literature describes strong associations between frailty and delirium in surgical units and community care settings, the present study only demonstrated a weak-to-moderate association between frailty and delirium in our ED.

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.

Improving Inferences About Null Effects With Bayes Factors and Equivalence Tests

Researchers often conclude an effect is absent when a null-hypothesis significance test yields a nonsignificant p value. However, it is neither logically nor statistically correct to conclude an effect is absent when a hypothesis test is not significant. We present two methods to evaluate the presence or absence of effects: Equivalence testing (based on frequentist statistics) and Bayes factors (based on Bayesian statistics). In four examples from the gerontology literature, we illustrate different ways to specify alternative models that can be used to reject the presence of a meaningful or predicted effect in hypothesis tests. We provide detailed explanations of how to calculate, report, and interpret Bayes factors and equivalence tests. We also discuss how to design informative studies that can provide support for a null model or for the absence of a meaningful effect. The conceptual differences between Bayes factors and equivalence tests are discussed, and we also note when and why they might lead to similar or different inferences in practice. It is important that researchers are able to falsify predictions or can quantify the support for predicted null effects. Bayes factors and equivalence tests provide useful statistical tools to improve inferences about null effects.