Development and validation of a frailty index in the Longitudinal Aging Study Amsterdam

The Longitudinal Aging Study Amsterdam: design and cohort update 2025

The Longitudinal Aging Study Amsterdam (LASA) is an ongoing prospective cohort study of older adults in the Netherlands, with data on multiple domains of functioning available over a period of more than 30 years of follow-up. The study started in 1992 with a nationally representative sample of older adults aged 55-84 years. Over the years, three refresher cohorts (two cohorts aged 55-64 years in 2002 and in 2012, and one cohort aged 60-86 years in 2024) were added. The main aim of LASA was to describe determinants, trajectories and consequences of (changes in) physical, cognitive, emotional and social functioning. LASA has multiple strengths, including its multidisciplinary character, the very long period of follow-up, and the cohort-sequential design which enables the study of longitudinal changes as well as historical time trends in functioning. So far, findings based on data from LASA have been reported in more than 800 scientific publications (see www.lasa-vu.nl ). In this article, we provide an update of the design and methods of LASA, including a description of several ancillary studies such as the Loneliness study and the COVID-19 study.

Frailty and Mortality Risk Among Dogs with Extreme Longevity: Development and Predictive Validity of a Clinical Frailty Index in the Exceptional Aging in Rottweilers Study

Frailty refers to a state of increased vulnerability to mortality and other adverse outcomes as a consequence of age-related decline in physiologic reserve and function. Comparative biomedical scientists are relied upon to innovate approaches to enhance understanding of the similarities and differences between humans and other animal species that can impact healthy aging. The research aim of this study was to develop a clinical frailty index (FI) in the Exceptional Aging in Rottweilers Study (EARS) and test its ability to predict all-cause mortality in elderly dogs. EARS is an ongoing lifetime cohort study of pet dogs with extreme longevity living in North America. Living 30% longer than the breed average, these dogs represent the canine counterpart to human centenarians. A 34-item FI (EARS-FI) was constructed to assess deficit accumulation using clinical data collected by telephone interviews with owners of 93 dogs with extreme longevity. Health deficits across multiple domains, including cognitive and sensory, cardiovascular and endocrine, and mobility, were included. The association between EARS-FI and subsequent mortality was tested in Kaplan-Meier survival analysis and in age-adjusted Cox proportional hazard models. Median (interquartile range) EARS-FI was 0.43 (0.38-0.50), and the estimated frailty limit was 0.68, consistent with data reported in humans with extreme longevity. Frailty index increased with increasing chronological age (p < 0.001). Deficit accumulation was significantly associated with increased mortality risk. Age-adjusted hazard ratio for mortality per 0.01 unit increase in FI was 1.05 (95%CI, 1.02-1.08; p = 0.001). This work provides the first demonstration of a strong association between frailty and mortality risk in pet dogs with extreme longevity. Notably, EARS-FI showed key features observed in the evaluation of frailty in aging human populations: heterogeneity, increase with chronological age, and estimated limit of <0.7. Validated here as a predictor of mortality in aged pet dogs, EARS-FI offers a useful tool for further comparative analyses of the linkages between deficit accumulation, mortality, and other adverse health outcomes.

Association of objectively measured walking speed with incident cardiovascular diseases in middle-aged and older Chinese adults

OBJECTIVE

To evaluate the association between objectively measured walking speed and cardiovascular disease (CVD) risk in middle-aged and elderly Chinese adults.

METHODS

A total of 3969 participants from the China Health and Retirement Longitudinal Study (CHARLS) were included in this study. Multilevel logistic and linear regression models (community-household-individual) were used to estimate the association between walking speed and the risk of CVD.

RESULTS

A total of 1037 participants had a CVD event during the follow-up period, including 776 (19.6%) cases of cardiac disease and 353 (8.9%) cases of stroke. Participants who walked faster had a lower risk of CVD (tertile 2: OR = 0.80, 95% CI: 0.67-0.97, P = 0.022; tertile 3: OR = 0.73, 95% CI: 0.60-0.89, P = 0.002). Further analysis showed that participants who walked faster also had a lower risk of cardiac disease and stroke (cardiac disease: tertile 2: OR = 0.91, 95% CI: 0.74-1.12, P = 0.368; tertile 3: OR = 0.85, 95% CI: 0.68-1.07, P = 0.161; stroke: tertile 2: OR = 0.33, 95% CI: 0.14-0.78, P = 0.012; tertile 3: OR = 0.30, 95% CI: 0.11-0.82, P = 0.019). The results were consistent in pre-specified subgroups by sex, age, and body mass index.

CONCLUSION

We found that faster, objectively measured walking speed was significantly associated with a lower risk of CVD, especially stroke, in middle-aged and elderly Chinese people.

The impact of frailty on the use of social services, medication and mortality risk: a cross-sectional study

BACKGROUND

Frailty is a common condition in older people, and its prevalence increases with age. With an ageing population, the adverse consequences of frailty cause an increasing appeal to the health care system. The impact of frailty on population level is often assessed using adverse health outcomes, such as mortality and medication use. Use of community nursing services and services offered through the Social Support Act are hardly used in assessing the impact of frailty. However, these services are important types of care use, especially in relation to ageing in place. In this cross-sectional study, we aimed to assess the impact of frailty on use of Social Support Act services, use of community nursing services, medication use, and mortality.

METHODS

We used a frailty index, the FI-HM37, that was based on data from the Dutch Public Health Monitor 2016, for which respondents ≥ 65 years of age were included (n = 233,498). The association between frailty, the use of Social Support Act services, community nursing services and medication use was assessed using the Zero Inflated Poisson (ZIP) regression method. Survival analysis using Cox proportional hazards regression was conducted to estimate the hazard ratios for the association between frailty and mortality.

RESULTS

The ZIP regression with a final sample size of 181,350 showed that frailty affected care use even after correcting for several covariates mentioned in the literature. For each unit increase in frailty index (FI) score, the relative probability of using zero Social Support services decreased with 7.7 (p < 0.001). The relative chance of zero community nursing services decreased with 4.0 (p < 0.001) for each unit increase in FI score. Furthermore, for each unit increase in FI score, the likelihood of zero medication use decreased with 2.9 (p < 0.001). Finally, for each unit increase in FI score, the mortality risk was 3.8 times higher (CI = 3.4-4.3; p < 0.001).

CONCLUSIONS

We demonstrated that frailty negatively affects the use of Social Support Act services, the use of community nursing services, medication use, and mortality risk. This study is the first to demonstrate the impact of frailty on Social Support Act services and community nursing services in the Netherlands. Findings emphasize the importance of frailty prevention for older people and public health policy.

The temporal sequence and reciprocal relationships of frailty, social isolation and loneliness in older adults across 21 years

BACKGROUND

It is unclear whether social isolation and loneliness may precede frailty status or whether frailty may precipitate social isolation and loneliness. We investigated the reciprocal and temporal sequence of social isolation, loneliness, and frailty among older adults across 21 years.

METHODS

We used seven waves of the Longitudinal Aging Study Amsterdam from 2302 Dutch older adults (M = 72.6 years, SD = 8.6, 52.1% female) ages 55 or older. Using random intercept cross-lagged panel models, we investigated between- and within-person associations of social isolation and loneliness with frailty. Frailty was measured using the Frailty Index. Loneliness was measured using the 11-item De Jong Gierveld Loneliness Scale. Social isolation was measured using a multi-domain 6-item scale.

RESULTS

Social isolation and loneliness were weakly correlated across waves. At the between-person level, individuals with higher levels of frailty tended to have higher levels of social isolation but not loneliness. At the within-person level, the cross-lagged paths indicated that earlier frailty status predicted future social isolation and loneliness over time. However, prior social isolation was not associated with subsequent frailty except at time point 5 (T5). Loneliness at specific time points (T1, T4 and T6) predicted greater frailty at later time points (T2, T5 and T7). The results also supported reciprocal and contemporaneous relations between social isolation, loneliness and frailty.

CONCLUSIONS

Social isolation and loneliness are potential outcomes of frailty. Public health policies and health practitioners should prioritise interventions targeting social connection among older adults with pre-frailty or frailty.

Impact of frailty in older people on health care demand: simulation modelling of population dynamics to inform service planning

Background

As populations age, frailty and the associated demand for health care increase. Evidence needed to inform planning and commissioning of services for older people living with frailty is scarce. Accurate information on incidence and prevalence of different levels of frailty and the consequences for health outcomes, service use and costs at population level is needed.

Objectives

To explore the incidence, prevalence, progression and impact of frailty within an ageing general practice population and model the dynamics of frailty-related healthcare demand, outcomes and costs, to inform the development of guidelines and tools to facilitate commissioning and service development.

Study design and methods

A retrospective observational study with statistical modelling to inform simulation (system dynamics) modelling using routine data from primary and secondary health care in England and Wales. Modelling was informed by stakeholder engagement events conducted in Hampshire, England. Data sources included the Royal College of General Practitioners Research and Surveillance Centre databank, and the Secure Anonymised Information Linkage Databank. Population prevalence, incidence and progression of frailty within an ageing cohort were estimated using the electronic Frailty Index tool, and associated service use and costs were calculated. Association of frailty with outcomes, service use and costs was explored with multistate and generalised linear models. Results informed development of a prototype system dynamics simulation model, exploring population impact of frailty and future scenarios over a 10-year time frame. Simulation model population projections were externally validated against retrospective data from Secure Anonymised Information Linkage.

Study population

The Royal College of General Practitioners Research and Surveillance Centre sample comprised an open cohort of the primary care population aged 50 + between 2006 and 2017 (approx. 2.1 million people). Data were linked to Hospital Episode Statistics data and Office for National Statistics death data. A comparable validation data set from Secure Anonymised Information Linkage was generated.

Baseline measures

Electronic Frailty Index score calculated annually and stratified into Fit, Mild, Moderate and Severe frailty categories. Other variables included age, sex, Index of Multiple Deprivation score, ethnicity and Urban/rural.

Outcomes

Frailty transitions, mortality, hospitalisations, emergency department attendances, general practitioner visits and costs.

Findings

Frailty is already present in people aged 50-64. Frailty incidence was 47 cases per 1000 person-years. Frailty prevalence increased from 26.5% (2006) to 38.9% (2017). Older age, higher deprivation, female sex, Asian ethnicity and urban location independently predict frailty onset and progression; 4.8% of 'fit' people aged 50-64 years experienced a transition to a higher frailty state in a year, compared to 21.4% aged 75-84. Individual healthcare use rises with frailty severity, but Mild and Moderate frailty groups have higher overall costs due to larger population numbers. Simulation projections indicate frailty will increase by 7.1%, from 41.5% to 48.7% between 2017 and 2027, and associated costs will rise by £5.8 billion (in England) over an 11-year period.

Conclusions

Simulation modelling indicates that frailty prevalence and associated service use and costs will continue to rise in the future. Scenario analysis indicates reduction of incidence and slowing of progression, particularly before the age of 65, has potential to substantially reduce future service use and costs, but reducing unplanned admissions in frail older people has a more modest impact. Study outputs will be collated into a commissioning toolkit, comprising guidance on drivers of frailty-related demand and simulation model outputs.

Study registration

This study is registered as NCT04139278 www.clinicaltrials.gov.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health and Social Care Delivery Research programme (NIHR award ref: 16/116/43) and is published in full in Health and Social Care Delivery Research; Vol. 12, No. 44. See the NIHR Funding and Awards website for further award information.

Definition and assessment of psychological frailty in older adults: A scoping review

OBJECTIVES

The confusion surrounding psychological frailty and its components prompts the need for a standardized conceptual definition. To address this, we aimed to (1) identify the psychological variables included in multicomponent frailty assessment instruments used with older adults and examine their operationalization; and (2) formulate a thorough conceptualization of psychological frailty based on the variables identified.

METHODS

This study followed the most recent recommendations for conducting scoping reviews and is reported in accordance with PRISMA-ScR guidelines. We systematically searched the CINAHL, MEDLINE, PsycInfo, Scopus, and Web of Science databases, with additional searches in Google Scholar and reference lists.

RESULTS

Sixteen instruments were identified. The results suggested that: (1) In multicomponent frailty assessment instruments, psychological variables are poorly represented; (2) A wide variety of psychological variables are included in the instruments, the most frequent being cognitive functioning and affective functioning (e.g., depressive symptoms, emotional loneliness, anxiety symptoms, poor coping, and suicidal ideation); and (3) The way in which variables are referred to and operationalized varies across instruments.

CONCLUSIONS

Including both cognitive and affective variables in psychological frailty assessments may lead to inaccuracies. We suggest distinguishing between two separate dimensions within psychological frailty: cognitive frailty and affective frailty. A conceptual definition for each dimension is provided. This proposal aims to advance the debate regarding the conceptualization and assessment of psychological frailty, with further research and discussion needed to ensure its practical applicability.

Inflammatory markers and frailty in home-dwelling elderly, a cross-sectional study

BACKGROUND

Low-grade, chronic inflammation during ageing, ("inflammageing"), is suggested to be involved in the development of frailty in older age. However, studies on the association between frailty, using the frailty index definition, and inflammatory markers are limited. The aim of this study was to investigate the relationship between inflammatory markers and frailty index (FI) in older, home-dwelling adults.

METHOD

Home-dwelling men and women aged ≥ 70 years old, living in South-East Norway were recruited and included in a cross-sectional study. The FI used in the current study was developed according to Rockwood's frailty index and included 38 variables, resulting in an FI score between 0 and 1 for each participant. Circulating inflammatory markers (IL-6, CRP, IGF-1, cystatin C, cathepsin S, and glycoprotein Acetyls) were analyzed from non-fasting blood samples using ELISA. Whole-genome PBMC transcriptomics was used to study the association between FI score and inflammation.

RESULTS

The study population comprised 403 elderly (52% women), with a median age of 74 years and a mean BMI of 26.2 kg/m2. The mean FI score for the total group was 0.15 (range 0.005-0.56). The group was divided into a frail group (FI score ≥ 0.25) and non-frail group. After adjusting for BMI, age, sex, and smoking in the whole group, IL-6, cathepsin S, cystatin C, and Gp-acetyls remained significant associated to FI score (IL-6: 0.002, 95% CI: 0.001, 0.002, cathepsin S: 6.7e-06, 95% CI 2.44e-06, 0.00001, cystatin C: 0.004, 95% CI: 0.002, 0.006, Gp- Acetyls: 0.09, 95% CI: 0.05, 0.13, p < 0.01 for all), while CRP and IGF-1 were not (0.0003, 95% CI: -00001, 0.0007, p = 0.13, (-1.27e-06), 95% CI: (-0.0003), 0.0003, p = 0.99). There was a significant association between FI score and inflammatory markers, and FI score and monocyte-specific gene expression.

CONCLUSIONS

We found an association between FI score and inflammatory markers, and between FI score and monocyte-specific gene expression among elderly subjects above 70 years of age. Whether inflammation is a cause or consequence of frailty and whether the progression of frailty can be attenuated by reducing inflammation remains to be clarified.

The phenotypic and genotypic association of grip strength with frailty, physical performance and functional limitations over time in older adults

OBJECTIVES

To replicate the phenotypic associations of grip strength with frailty, physical performance and functional limitations in older adults for longer follow-up periods and to examine whether these associations are due to shared genetic factors.

METHODS

In total 2,262 participants 55 years and older with follow-up data up to 23 years (Nobservations = 8,262) from the Longitudinal Aging Study Amsterdam were included. Weighted polygenic risk scores for grip strength (PRS-GS) were built using the genome-wide meta-analysis results from UK Biobank as reference. Grip strength was measured two times on each hand using a dynamometer. Frailty index (FI) and frailty phenotype were operationalised following standard procedures. Performance tests included a timed walk test, a repeated chair stands test and put on-take off cardigan test. Functional limitations were assessed using a questionnaire with six items.

RESULTS

Higher grip strength was phenotypically associated with lower FI (b = -0.013, 95% CI (-0.016, -0.009)), better physical performance (b = 0.040, 95% CI (0.026, 0.054)) and less functional limitations (OR = 0.965, 95% CI (0.954, 0.977)) over time for follow-up periods up to 23 years. However, PRS-GS was not associated with any of the traits.

CONCLUSION

The phenotypic associations between grip strength, frailty, physical performance and functional limitations were replicated for follow-up periods up to 23 years. However, the associations between the traits could not be explained by shared genetics potentially indicating a more relevant involvement of non-genetic factors.

Application of MFI-5 in severe complications and unfavorable outcomes after radical resection of colorectal cancer

BACKGROUND

Frailty is considered a characteristic manifestation of physiological decline in multiple organ systems, which significantly increases the vulnerability of elderly individuals with colorectal cancer (CRC) and is associated with a poor prognosis. While studies have demonstrated that the 11-factor Modified Frailty Index (mFI-11) can effectively predict adverse outcomes following radical resection of CRC, there is a lack of research on the applicability of the 5-factor Modified Frailty Index (mFI-5) within this patient population.

METHODS

In this retrospective analysis, we examined a cohort of CRC patients aged 65 years and above who had undergone radical resection. For each patient, we calculated their mFI-5 score, considering a score of ≥ 2 as an indication of frailty. We conducted univariate and multivariate analyses to assess the association between the mFI-5 and adverse outcomes as well as postoperative complications.

RESULTS

Patients with an mFI-5 score ≥ 2 exhibited a significantly higher incidence of serious postoperative complications (53% vs. 30%; P = 0.001) and experienced a longer hospital stay [19.00 (15.00-24.50) vs. 17.00 (14.00-20.00); P < 0.05]. Notably, an mFI-5 score greater than 2 emerged as an independent risk factor for severe postoperative complications (odds ratio: 2.297; 95% confidence interval: 1.216 to 4.339; P = 0.01). Furthermore, the mFI-5 score displayed predictive capabilities for severe postoperative complications with an area under the receiver operating characteristic (ROC) curve of 0.629 (95% confidence interval: 0.551 to 0.707; P < 0.05).

CONCLUSION

The mFI-5 demonstrates a high level of sensitivity in predicting serious complications, prolonged hospital stays, and mortality following radical resection of colorectal carcinoma. As a practical clinical assessment tool, the mFI-5 enables the identification of high-risk patients and facilitates preoperative optimization.

Physiologically based pharmacokinetic (PBPK) modelling of oral drug absorption in older adults - an AGePOP review

The older population consisting of persons aged 65 years or older is the fastest-growing population group and also the major consumer of pharmaceutical products. Due to the heterogenous ageing process, this age group shows high interindividual variability in the dose-exposure-response relationship and, thus, a prediction of drug safety and efficacy is challenging. Although physiologically based pharmacokinetic (PBPK) modelling is a well-established tool to inform and confirm drug dosing strategies during drug development for special population groups, age-related changes in absorption are poorly accounted for in current PBPK models. The purpose of this review is to summarise the current state-of-knowledge in terms of physiological changes with increasing age that can influence the oral absorption of dosage forms. The capacity of common PBPK platforms to incorporate these changes and describe the older population is also discussed, as well as the implications of extrinsic factors such as drug-drug interactions associated with polypharmacy on the model development process. The future potential of this field will rely on addressing the gaps identified in this article, which can subsequently supplement in-vitro and in-vivo data for more robust decision-making on the adequacy of the formulation for use in older adults and inform pharmacotherapy.

The sublingual microcirculation and frailty index in chronic kidney disease patients

OBJECTIVE

To examine the relationship between sublingual microcirculatory measures and frailty index in those attending a kidney transplant assessment clinic.

METHODS

Patients recruited had their sublingual microcirculation taken using sidestream dark field videomicroscopy (MicroScan, Micro Vision Medical, Amsterdam, the Netherlands) and their frailty index score using a validated short form via interview.

RESULTS

A total of 44 patients were recruited with two being excluded due to microcirculatory image quality scores exceeding 10. The frailty index score indicated significant correlations with total vessel density (p < .0001, r = -.56), microvascular flow index (p = .004, r = -.43), portion of perfused vessels (p = .0004, r = -.52), heterogeneity index (p = .015, r = .32), and perfused vessel density (p < .0001, r = -.66). No correlation was shown between the frailty index and age (p = .08, r = .27).

CONCLUSIONS

There is a relationship between the frailty index and microcirculatory health in those attending a kidney transplant assessment clinic, that is not confounded by age. These findings suggest that the impaired microcirculation may be an underlying cause of frailty.

Frailty detection by healthcare professionals: a systematic review of the available English and French tools and their validation

BACKGROUND

There is a wide variety of frailty detection tools, but no gold standard. Choosing the most appropriate tool can therefore be complicated. Our systematic review seeks to provide useful data on the frailty detection tools available to help healthcare professionals in choosing a tool.

METHOD

We systematically searched for articles published between January 2001 and December 2022 in three electronic databases. Articles were to be written in English or French and were to discuss a frailty detection tool used by healthcare professionals in a population without specific health conditions. Any self-testing, physical testing or biomarkers were excluded. Systematic reviews and meta-analyses were also excluded. Data were extracted from two coding grids; one for the criteria used by the tools to detect frailty and the other for the evaluation of clinimetric parameters. The quality of the articles was assessed using QUADAS-2.

RESULTS

A total of 52 articles, covering 36 frailty detection tools, were included and analysed in the systematic review. Forty-nine different criteria were identified, with a median of 9 (IQR 6-15) criteria per tool. Regarding the evaluation of tool performances, 13 different clinimetric properties were identified, with a mean of 3.6 (± 2.2) properties assessed per tool.

CONCLUSION

There is considerable heterogeneity in the criteria used to detect frailty, as well as in the way tools are evaluated.

Racial, Ethnic, and Socioeconomic Differences in a Deficit Accumulation Frailty Index in the Multiethnic Cohort Study

BACKGROUND

Frailty status has been sparsely studied in some groups including Native Hawaiians and Asian Americans.

METHODS

We developed a questionnaire-based deficit accumulation frailty index (FI) in the Multiethnic Cohort (MEC) and examined frailty status (robust, FI 0 to <0.2, prefrail, FI 0.2 to <0.35, and frail FI ≥ 0.35) among 29 026 men and 40 756 women.

RESULTS

After adjustment for age, demographic, lifestyle factors, and chronic conditions, relative to White men, odds of being frail was significantly higher (34%-54%) among African American, Native Hawaiian, and other Asian American men, whereas odds was significantly lower (36%) in Japanese American men and did not differ in Latino men. However, among men who had high school or less, none of the groups displayed significantly higher odds of prefrail or frail compared with White men. Relative to White women, odds of being frail were significantly higher (14%-33%) in African American and Latino women, did not differ for other Asian American women and lower (14%-36%) in Native Hawaiian and Japanese American women. These racial and ethnic differences in women were observed irrespective of education. Risk of all-cause mortality was higher in prefrail and frail men than robust men (adjusted hazard ratio [HR] = 1.69, 1.59-1.81; HR = 3.27, 3.03-3.53); results were similar in women. All-cause mortality was significantly positively associated with frailty status and frailty score across all sex, race, and ethnic groups.

CONCLUSIONS

Frailty status differed significantly by race and ethnicity and was consistently associated with all-cause mortality. The FI may be a useful tool for aging studies in this multiethnic population.

Frailty transitions and prevalence in an ageing population: longitudinal analysis of primary care data from an open cohort of adults aged 50 and over in England, 2006-2017

INTRODUCTION

frailty is common in older adults and is associated with increased health and social care use. Longitudinal information is needed on population-level incidence, prevalence and frailty progression to plan services to meet future population needs.

METHODS

retrospective open cohort study using electronic health records of adults aged ≥50 from primary care in England, 2006-2017. Frailty was calculated annually using the electronic Frailty Index (eFI). Multistate models estimated transition rates between each frailty category, adjusting for sociodemographic characteristics. Prevalence overall for each eFI category (fit, mild, moderate and severe) was calculated.

RESULTS

the cohort included 2,171,497 patients and 15,514,734 person-years. Frailty prevalence increased from 26.5 (2006) to 38.9% (2017). The average age of frailty onset was 69; however, 10.8% of people aged 50-64 were already frail in 2006. Estimated transitions from fit to any level of frailty were 48/1,000 person-years aged 50-64, 130/1,000 person-years aged 65-74, 214/1,000 person-years aged 75-84 and 380/1,000 person-years aged ≥ 85. Transitions were independently associated with older age, higher deprivation, female sex, Asian ethnicity and urban dwelling. Mean time spent in each frailty category decreased with age, with the longest period spent in severe frailty at all ages.

CONCLUSIONS

frailty is prevalent in adults aged ≥50 and time spent in successive frailty states is longer as frailty progresses, resulting in extended healthcare burden. Larger population numbers and fewer transitions in adults aged 50-64 present an opportunity for earlier identification and intervention. A large increase in frailty over 12 years highlights the urgency of informed service planning in ageing populations.

Development of a frailty index from the Dutch public health monitor 2016 and investigation of its psychometric properties: a cross-sectional study

BACKGROUND

Frailty in older adults is an increasing challenge for individuals, health care organizations and public health, both globally and in The Netherlands. To focus on frailty prevention from a public health perspective, understanding of frailty status is needed. To enable measurement of frailty within a health survey that currently does not contain an established frailty instrument, we aimed to construct a frailty index (FI) and investigate its psychometric properties.

METHODS

We conducted a cross-sectional study using data from the Dutch Public Health Monitor (DPHM), including respondents aged ≥ 65 years (n = 233,498). Forty-two health deficits were selected based on literature, previously constructed FIs, face validity and standard criteria for FI construction. Deficits were first explored by calculating Cronbach's alpha, point-polyserial correlations, and factor loadings. Thereafter, we used the Graded Response Model (GRM) to assess item difficulty, item discrimination, and category thresholds.

RESULTS

Cronbach's alpha for the 42 items was 0.91. Thirty-seven deficits showed strong psychometric properties: they scored above the cutoff values for point-polyserial correlations (0.3) or factor loadings (0.4) and had moderate to very high discrimination parameters (≥ 0.65). These deficits were retained in the scale. Retaining the deficits with favorable measurement properties and removing the remaining deficits resulted in the FI-HM37.

CONCLUSION

The FI-HM37 was developed, an FI with 37 deficits indicative of frailty, both statistically and conceptually. Our results indicate that health monitors can be used to measure frailty, even though they were not directly designed to do so. The GRM is a suitable approach for deficit selection, resulting in a psychometrically strong scale, that facilitates assessment of frailty levels using the DPHM.

The impact of COVID-19 related adversity on the course of mental health during the pandemic and the role of protective factors: a longitudinal study among older adults in The Netherlands

PURPOSE

Many studies report about risk factors associated with adverse changes in mental health during the COVID-19 pandemic while few studies report about protective and buffering factors, especially in older adults. We present an observational study to assess protective and buffering factors against COVID-19 related adverse mental health changes in older adults.

METHODS

899 older adults (55 +) in the Netherlands were followed from 2018/19 to two pandemic time points (June-October 2020 and March-August 2021). Questionnaires included exposure to pandemic-related adversities ("COVID-19 exposure"), depressive and anxiety symptoms, loneliness, and pre-pandemic functioning. Linear regression analyses estimated main effects of COVID-19 exposure and protective factors on mental health changes; interaction effects were tested to identify buffering factors.

RESULTS

Compared to pre-pandemic, anxiety symptoms, depression symptoms and loneliness increased. A higher score on the COVID-19 adversity index was associated with stronger negative mental health changes. Main effects: internet use and high mastery decreased depressive symptoms; a larger network decreased anxiety symptoms; female gender, larger network size and praying decreased loneliness. COVID-19 vaccination buffered against COVID-19 exposure-induced anxiety and loneliness, a partner buffered against COVID-19 exposure induced loneliness.

CONCLUSION

Exposure to COVID-19 adversity had a cumulative negative impact on mental health. Improving coping, finding meaning, stimulating existing religious and spiritual resources, network interventions and stimulating internet use may enable older adults to maintain mental health during events with large societal impact, yet these factors appear protective regardless of exposure to specific adversities. COVID-19 vaccination had a positive effect on mental health.

Adverse Childhood Experiences and frailty in later life: a prospective population-based cohort study

BACKGROUND

The deficit accumulation method considers the ageing process underlying frailty as a random accumulation of health deficits.

OBJECTIVE

Although Adverse Childhood Experiences (ACE) have consistently been associated with the onset of mental disorders and somatic diseases during adolescence and midlife, it remains unknown whether ACE still exert detrimental health effects in late life. Therefore, we examined cross-sectionally and prospectively the association between ACE and frailty among community-dwelling older people.

DESIGN

Based on the health-deficit accumulation method, a Frailty Index was calculated with values ≥0.25 considered as frail. ACE were measured by a validated questionnaire. The cross-sectional association was examined by logistic regression among 2,176 community dwelling participants aged 58-89 years. The prospective association was examined by Cox-regression among 1,427 non-frail participants during a 17-year follow-up. Interactions with age and sex were tested and analyses were adjusted for potential confounders.

SETTING

The present study was embedded in the Longitudinal Aging Study Amsterdam.

RESULTS

ACE and frailty were positively associated at baseline (OR = 1.88; 95% CI = 1.46-2.42; P = 0.05). Among non-frail participants at baseline (n = 1,427), ACE interacted with age on the prediction of frailty. Stratified analyses showed that a history of ACE only resulted in a higher hazard rate for the incidence of frailty among those aged ≥70 years (HR = 1.28; P = 0.044).

CONCLUSION

Even in the oldest-old, ACE still lead to an accelerated rate of the accumulation of health deficits and therefore contribute to the onset of frailty.

Progression of frailty as measured by a cumulative deficit index: A systematic review

BACKGROUND

Frailty is a risk factor for adverse health outcomes. There is a paucity of literature on frailty progression defined by a cumulative deficit model among community dwelling older people. The objective of this review was to synthesise evidence on these changes in health and mortality among community-dwelling older people.

METHODS

Six databases (Medline, Embase, CINAHL, Cochrane, PsycInfo, Web of Science) and a clinical trials registry were searched in July 2021. The inclusion criteria were studies using a frailty index and providing information on transition between frailty states or to death in community-dwelling older people aged ≥ 50. Exclusion criteria were studies examining specific health conditions, conference abstracts and non-English studies. To standardise the follow-up period and facilitate comparison, we converted the transition probabilities to annual transition rates.

RESULTS

Two reviewers independently screened 5078 studies and 61 studies were included for analysis. Of these, only three used the same frailty state cut-points to facilitate cross-cohort comparison. This review found that frailty tends to increase with time, people who are frail at baseline have greater likelihood to progress in frailty and die, and the main factor that accelerates frailty progression is age. Other risk factors for progression are having chronic disease, smoking, obesity, low-income or/and low-education levels. A frailty index is an accurate predictor of adverse outcomes and death.

DISCUSSION

This systematic review demonstrated that worsening in frailty was a common frailty transition, and older people who are frail at baseline are more likely to die. A frailty index has significant power to predict adverse health outcomes. It is a useful tool for within-cohort comparison but there are challenges comparing different cohorts due to dependence of frailty progression on age and differences in how frailty index is defined and measured.

Frailty trajectories and associated factors in the years prior to death: evidence from 14 countries in the Survey of Health, Aging and Retirement in Europe

BACKGROUND

Age-related changes in frailty have been documented in the literature. However, the evidence regarding changes in frailty prior to death is scarce. Understanding patterns of frailty progression as individuals approach death could inform care and potentially lead to interventions to improve individual's well-being at the end of life. In this paper, we estimate the progression of frailty in the years prior to death.

METHODS

Using data from 8,317 deceased participants of the Survey of Health, Ageing, and Retirement in Europe, we derived a 56-item Frailty Index. In a coordinated analysis of repeated measures of the frailty index in 14 countries, we fitted growth curve models to estimate trajectories of frailty as a function of distance to death controlling both the level and rate of frailty progression for age, sex, years to death and dementia diagnosis.

RESULTS

Across all countries, frailty before death progressed linearly. In 12 of the 14 countries included in our analyses, women had higher levels of frailty close to the time of death, although they progressed at a slower rate than men (e.g. Switzerland (-0.008, SE = 0.003) and Spain (-0.004, SE = 0.002)). Older age at the time of death and incident dementia were associated with higher levels and increased rate of change in frailty, whilst higher education was associated with lower levels of frailty in the year preceding death (e.g. Denmark (0.000, SE = 0.001)).

CONCLUSION

The progression of frailty before death was linear. Our results suggest that interventions aimed at slowing frailty progression may need to be different for men and women. Further longitudinal research on individual patterns and changes of frailty is warranted to support the development of personalized care pathways at the end of life.

Prevalence and association of frailty with SARS-CoV-2 infection in older adults in Southern Switzerland-Findings from the Corona Immunitas Ticino Study

BACKGROUND

Frailty is an age-associated state of increased vulnerability to stressors that strongly predicts poor health outcomes. Epidemiological evidence on frailty is limited during the COVID-19 pandemic, and whether frailty is associated with the risk of infection is unknown.

OBJECTIVES

We derived a robust Frailty Index (FI) to measure the prevalence of frailty and its risk factors in community-dwelling older adults in Southern Switzerland (Ticino), and we explored the association between frailty and serologically confirmed SARS-CoV-2 infection.

METHODS

In September 2020, we recruited a random sample of community-dwelling older adults (65 +) in the Corona Immunitas Ticino prospective cohort study (CIT) and assessed a variety of lifestyle and health characteristics. We selected 30 health-related variables, computed the Rockwood FI, and applied standard thresholds for robust (FI < 0.1), pre-frail (0.1 ≤ FI < 0.21), and frail (FI ≥ 0.21).

RESULTS

Complete data for the FI was available for 660 older adults. The FI score ranged between zero (no frailty) and 0.59. The prevalence of frailty and pre-frailty were 10.3% and 48.2% respectively. The log-transformed FI score increased by age similarly in males and females, on average by 2.8% (p < 0.001) per one-year increase in age. Out of 481 participants with a valid serological test, 11.2% were seropositive to either anti-SARS-CoV-2 IgA or IgG. The frailty status and seropositivity were not statistically associated (p = 0.236).

CONCLUSION

Advanced age increases the risk of frailty. The risk of COVID-19 infection in older adults may not differ by frailty status.

10-Year Follow-up of the Original Faroese Septuagenarian Cohort: Focus on Frailty and Association With All-cause Mortality

Little is known about the health status of Faroese people reaching high age. The purpose of this study was to elucidate the health status of older adults in a small-scale society with emphasis on frailty and all-cause mortality. In this 10-year follow-up study, 347 Faroese citizens aged 80 to 84 from the Faroese Septuagenarian cohort participated. A detailed health examination was conducted, in addition to self-reported questionnaire. We constructed a 40-item Frailty Index (FI) to assess frailty. Survival and mortality risks were analyzed using Kaplan-Meier curves and Cox proportional hazard model. Median FI score was 0.28 ranging from 0.09 to 0.7; 71 (21%) individuals were least frail, 244 (67%) moderately frail, and 41 (12%) were most frail. Frailty and sex were statistically significantly associated with mortality; being male was associated with hazard ratio (HR) of 4.05 [CI 1.73, 9.48], and being most frail with HR of 6.2 [CI 1.84, 21.3]. Classification of octogenarians as least/moderately frail may be an opportunity to initiate interventions to prevent or delay frailty in this population stratum.

Efficacy and Safety of Dapagliflozin According to Frailty in Patients With Heart Failure: A Prespecified Analysis of the DELIVER Trial

BACKGROUND

Frailty is increasing in prevalence. Because patients with frailty are often perceived to have a less favorable risk/benefit profile, they may be less likely to receive new pharmacologic treatments. We investigated the efficacy and tolerability of dapagliflozin according to frailty status in patients with heart failure with mildly reduced or preserved ejection fraction randomized in DELIVER (Dapagliflozin Evaluation to Improve the Lives of Patients With Preserved Ejection Fraction Heart Failure).

METHODS

Frailty was measured using the Rockwood cumulative deficit approach. The primary end point was time to a first worsening heart failure event or cardiovascular death.

RESULTS

Of the 6263 patients randomized, a frailty index (FI) was calculable in 6258. In total, 2354 (37.6%) patients had class 1 frailty (FI ≤0.210; ie, not frail), 2413 (38.6%) had class 2 frailty (FI 0.211-0.310; ie, more frail), and 1491 (23.8%) had class 3 frailty (FI ≥0.311; ie, most frail). Greater frailty was associated with a higher rate of the primary end point (per 100 person-years): FI class 1, 6.3 (95% CI 5.7-7.1); class 2, 8.3 (7.5-9.1); and class 3, 13.4 (12.1-14.7; P<0.001). The effect of dapagliflozin (as a hazard ratio) on the primary end point from FI class 1 to 3 was 0.85 (95% CI, 0.68-1.06), 0.89 (0.74-1.08), and 0.74 (0.61-0.91), respectively (Pinteraction=0.40). Although patients with a greater degree of frailty had worse Kansas City Cardiomyopathy Questionnaire scores at baseline, their improvement with dapagliflozin was greater than it was in patients with less frailty: placebo-corrected improvement in Kansas City Cardiomyopathy Questionnaire Overall Summary Score at 4 months in FI class 1 was 0.3 (95% CI, -0.9 to 1.4); in class 2, 1.5 (0.3-2.7); and in class 3, 3.4 (1.7-5.1; Pinteraction=0.021). Adverse reactions and treatment discontinuation, although more frequent in patients with a greater degree of frailty, were not more common with dapagliflozin than with placebo irrespective of frailty class.

CONCLUSIONS

In DELIVER, frailty was common and associated with worse outcomes. The benefit of dapagliflozin was consistent across the range of frailty studied. The improvement in health-related quality of life with dapagliflozin occurred early and was greater in patients with a higher level of frailty.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03619213.

Frailty and risks of all-cause and cause-specific death in community-dwelling adults: a systematic review and meta-analysis

BACKGROUND

The associations of frailty with all-cause and cause-specific mortality remain unclear. Therefore, we performed this meta-analysis to fill this gap.

METHODS

We searched the PubMed and Embase databases through June 2022. Prospective cohort studies or clinical trials examining frailty were evaluated, and the multiple adjusted risk estimates of all-cause and cause-specific mortality, such as death from cardiovascular disease (CVD), cancer, respiratory illness, dementia, infection, and coronavirus disease 2019 (COVID-19), were included. A random effects model was used to calculate the summary hazard ratio (HR).

RESULTS

Fifty-eight studies were included for the qualitative systematic review, of which fifty-six studies were eligible for the quantitative meta-analysis, and the studies included a total of 1,852,951 individuals and more than 145,276 deaths. Compared with healthy adults, frail adults had a significantly higher risk of mortality from all causes (HR 2.40; 95% CI 2.17-2.65), CVD (HR 2.64; 95% CI 2.20-3.17), respiratory illness (HR 4.91; 95% CI 2.97-8.12), and cancer (HR 1.97; 95% CI 1.50-2.57). Similar results were found for the association between prefrail adults and mortality risk. In addition, based on the studies that have reported the HRs of the mortality risk per 0.1 and per 0.01 increase in the frailty index, we obtained consistent results.

CONCLUSIONS

The present study demonstrated that frailty was not only significantly related to an increased risk of all-cause mortality but was also a strong predictor of cause-specific mortality from CVD, cancer, and respiratory illness in community-dwelling adults. More studies are warranted to clarify the relationship between frailty and cause-specific mortality from dementia, infection, and COVID-19.

TRIAL REGISTRATION

PROSPERO (CRD42021276021).

Sacubitril/Valsartan and Frailty in Patients With Heart Failure and Preserved Ejection Fraction

BACKGROUND

Frailty is an increasingly common problem, and frail patients are less likely to receive new pharmacologic therapies because the risk-benefit profile is perceived to be less favorable than in nonfrail patients.

OBJECTIVES

This study investigated the efficacy of sacubitril/valsartan according to frailty status in 4,796 patients with heart failure with preserved ejection fraction randomized in the PARAGON-HF (Prospective Comparison of ARNI With ARB Global Outcomes in Heart Failure With Preserved Ejection Fraction) trial.

METHODS

Frailty was measured by using the Rockwood cumulative deficit approach. The primary endpoint was total heart failure hospitalizations or cardiovascular death.

RESULTS

A frailty index (FI) was calculable in 4,795 patients. In total, 45.2% had class 1 frailty (FI ≤0.210, not frail), 43.5% had class 2 frailty (FI 0.211-0.310, more frail), and 11.4% had class 3 frailty (FI ≥0.311, most frail). There was a graded relationship between FI class and the primary endpoint, with a significantly higher risk associated with greater frailty (class 1: reference; class 2 rate ratio: 2.19 [95% CI: 1.85-2.60]; class 3 rate ratio: 3.29 [95% CI: 2.65-4.09]). The effect of sacubitril/valsartan vs valsartan on the primary endpoint from lowest to highest FI class (as a rate ratio) was: 0.98 [95% CI: 0.76-1.27], 0.92 [95% CI: 0.76-1.12], and 0.69 [95% CI: 0.51-0.95]), respectively (P_interaction = 0.23). When FI was examined as a continuous variable, the interaction with treatment was significant for the primary outcome (P_interaction = 0.002) and total heart failure hospitalizations (P_interaction < 0.001), with those most frail deriving greater benefit.

CONCLUSIONS

Frailty was common in heart failure with preserved ejection fraction and associated with worse outcomes. Compared with valsartan, sacubitril/valsartan seemed to show a greater reduction in the primary endpoint with increasing frailty, although this was not significant when FI was examined as a categorical variable. (Prospective Comparison of ARNI With ARB Global Outcomes in Heart Failure With Preserved Ejection Fraction [PARAGON-HF]; NCT01920711).

Physical activity as a risk or protective factor for falls and fall-related fractures in non-frail and frail older adults: a longitudinal study

Background

Physical activity may be both a risk and protective factor for falls and fall-related fractures. Despite its positive effects on muscle and bone health, physical activity also increases exposure to situations where falls and fractures occur. This paradox could possibly be explained by frailty status. Therefore, the aim of this study was to investigate the associations between physical activity and both falls and fractures, and to determine whether frailty modifies the association of physical activity with falls, and fractures.

Methods

Data of 311 community-dwelling participants aged 75 years or older from the Longitudinal Aging Study Amsterdam, who participated in a three-year longitudinal study with five nine-monthly measurements between 2015/2016 and 2018/2019. Their mean age was 81.1 (SD 4.8) years and frailty was present in 30.9% of the participants. Physical activity in minutes per day was objectively assessed with an inertial sensor (Actigraph) for seven consecutive days. Falls and fractures were assessed every nine months using self-report during an interview over a follow-up period of three years. Frailty was determined at baseline using the frailty index. Associations were estimated using longitudinal logistic regression analyses based on generalized estimating equations.

Results

No association between physical activity and falls was found (OR = 1.00, 95% CI: 0.99–1.00). Fall risk was higher in frail compared to non-frail adults (OR = 2.21, 95% CI: 1.33–3.68), but no effect modification was seen of frailty on the association between physical activity and falls. Also no relation between physical activity and fractures was found (OR = 1.00, 95% CI: 0.99–1.01). Fracture risk was higher in frail compared to non-frail adults (OR = 2.81, 95% CI: 1.02–7.75), but also no effect modification of frailty was present in the association between physical activity and fractures.

Conclusions

No association between physical activity and neither falls nor fractures was found, and frailty appeared not to be an effect modifier. However, frailty was a risk factor for falls and fractures in this population of older adults. Our findings suggest that physical activity can be safely recommended in non-frail and frail populations for general health benefits, without increasing the risk of falls.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03383-y.

Low physical activity is the strongest factor associated with frailty phenotype and frailty index: data from baseline phase of Birjand Longitudinal Aging Study (BLAS)

Background

Frailty is the most complicated expression of aging that is related to disability or multi-morbidity. The aim of the present study was to estimate the prevalence of frailty and its associated factors among community-dwelling aged population.

Methods

A total of 1529 eligible community- dwelling older adults (≥ 60 years) were enrolled in the baseline phase of Birjand Longitudinal Aging Study (BLAS) from 2019 to 2020. Their frailty status was assessed using the Fried’s frailty phenotype and frailty index. Sociodemographic factors, including sex, age, marital status, and education level, were collected. Health status assessment included the history of hypertension, diabetes mellitus, cardiovascular disease, Alzheimer’s diseases and dementia, and other health conditions. Furthermore, functional assessment (ADL, IADL) and anthropometric measurements including height, weight, waist, calf, and mid-arm circumference were made and the body mass index was calculated. The nutrition status and polypharmacy (use 3 or more medication) were also evaluated.

Results

The prevalence of frailty was 21.69% according to the frailty phenotype and 23.97% according to the frailty index. A multiple logistic regression model showed a strong association between low physical activity and frailty phenotype (OR = 36.31, CI = 16.99–77.56, P < 0.01), and frailty index (OR = 15.46, CI = 5.65–42.34, P < 0.01). Other factors like old age (≥80), female sex, malnutrition, polypharmacy, obesity, and arthritis were also associated with frailty. The Kappa coefficient of the agreement between these two instruments was 0.18.

Conclusion

It seems that low physical activity is the most important determinant of frailty. Low physical activity and some other factors may be preventable or modifiable and thus serve as clinically relevant targets for intervention.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03135-y.

Frailty in Parkinson's disease and its association with early dementia: A longitudinal study

INTRODUCTION

Frailty is recognized as a clinical condition associated with increased vulnerability for developing negative health outcomes but has been little studied in patients with Parkinson's disease (PD). Here, we investigated the risk of frailty in de novo PD patients and its association with subsequent development of dementia.

METHODS

We conducted a three-year longitudinal population-based study of 192 drug-naive newly diagnosed PD patients and 172 controls (No-PD) matched for age, sex, and education. Frailty was measured using the frailty index (FI). Logistic regression models, adjusting for potential confounders, were conducted to assess the association between frailty at the time of PD diagnosis and the subsequent odds for developing PD dementia during follow-up.

RESULTS

The mean baseline FI score was higher in the PD (0.21 ± 0.10) than in the No-PD group (0.11 ± 0.07, p < 0.001). One-third of PD patients had high-FI (>0,25), compared to 5% in the no-PD group. Participants with PD had an increased risk to present frailty with an odds ratio (OR) of 6.68 (SE 2.70 IC 95% [3.15; 15.62], p-value <0.001) compared to the No-PD group. PD Participants with greater FI measured at baseline had increased odds of having dementia within three years of follow-up, after adjustment for age and sex (OR 2.91 SE 1.00 IC 95% [1.54; 5.99] p-value = 0.002).

CONCLUSION

Frailty is common in people with newly diagnosed PD and associated with increased odds for subsequent development of dementia in a three-year follow-up. This study emphasizes the prognostic importance of frailty in PD from the earliest clinical stages.

Inequalities in Frailty Among Older Turkish and Moroccan Immigrants and Native Dutch: Data from the Longitudinal Aging Study Amsterdam

Very few studies have investigated frailty among older immigrants in Europe. The aim of the current study was to investigate inequalities in frailty in young-olds related to gender, educational level and country of origin, as well as intersections between these characteristics. Cross-sectional data were used from older Turkish and Moroccan immigrants (n = 466) and native Dutch (n = 1,020), all aged 55-65 years and participating in the Longitudinal Aging Study Amsterdam. Frailty was assessed with a 30-item frailty index, based on the deficit accumulation approach. Frailty was higher among women, lower educated, and people with a migration background. Of all groups considered, frailty levels were the highest among Turkish immigrants. No statistically significant interaction effects between gender, educational level and country of origin were found. When targeting frailty interventions, special attention should be devoted to older immigrants, as they are the most vulnerable group with the highest frailty levels.

Do changes in frailty, physical functioning, and cognitive functioning predict mortality in old age? Results from the Longitudinal Aging Study Amsterdam

Background

The ability to accurately predict survival in older adults is crucial as it guides clinical decision making. The added value of using various health indicators as well as changes in these indicators for predicting mortality remains unclear. The aim of this study was to investigate whether changes in health indicators such as frailty and physical performance improve mortality predictions in old age.

Methods

This is a population based prospective cohort study on 995 community-dwelling people aged 68–92 years from the Longitudinal Aging Study Amsterdam. Two measurements at a three-year interval (1995/1996 and 1998/1999) were available for the frailty index, frailty phenotype, grip strength, walking speed, and Mini-Mental State Examination (MMSE). Cox regression was used to analyze mortality risks associated with the current health status and changes in health, with mortality data up to 2017. The extent to which these health indicators improved mortality predictions compared to models with age and sex only was assessed by the area under the receiver operating characteristic curve (AUC).

Results

The AUC of age and sex for five-year mortality was 72.8% (95% CI 69.0 – 76.5) and was the lowest in the oldest old (age > 80.5 years). The added AUC of the current status of health indicators ranged from 0.7 to 3.3%. The added AUC of the three-year change was lower, ranging from -0.0 to 1.1%, whereas the added AUC of three-year change and current status combined was similar to current status alone, ranging from 0.6 to 3.2%. Across age, the added AUC of current status was highest in the oldest old, however there was no such pattern using three-year change. Overall, the frailty index appeared to improve mortality predictions the most, followed by the frailty phenotype, MMSE, grip strength, and walking speed.

Conclusions

Current health status improved mortality predictions better than changes in health. Its contribution was highest in the oldest old, but the added value to models with age and sex only was limited.

Frailty in the oldest old: is the current level or the rate of change more predictive of mortality?

BACKGROUND

It is unclear whether frailty index (FI) change captures mortality risk better than and independently of the current FI level, i.e. whether a regular FI assessment among older adults provides additional insights for mortality risk stratification or not.

METHODS

We used data from the LASA 75-PLUS-study, which monitored health among 508 older adults (75+) between 2016 and 2019 every 9 months. Joint models for longitudinal and time-to-event data were used to assess the impact of both current FI and within-person FI change during the last year on mortality risk.

RESULTS

Twenty percent of the participants died during 4.5 years of follow-up. Adding within-person FI change to the current FI model improved model fit and it showed that FI increases during the last year were associated with an increase in mortality risk. Consequently, the effect of the current FI decreased considerably and became statistically non-significant.

CONCLUSIONS

The rate of FI change was more important than the current FI level for short-term mortality prediction among the oldest old, which highlights the benefits of regular frailty assessments.

Trajectories of Frailty With Aging: Coordinated Analysis of Five Longitudinal Studies

BACKGROUND AND OBJECTIVES

There is an urgent need to better understand frailty and its predisposing factors. Although numerous cross-sectional studies have identified various risk and protective factors of frailty, there is a limited understanding of longitudinal frailty progression. Furthermore, discrepancies in the methodologies of these studies hamper comparability of results. Here, we use a coordinated analytical approach in 5 independent cohorts to evaluate longitudinal trajectories of frailty and the effect of 3 previously identified critical risk factors: sex, age, and education.

RESEARCH DESIGN AND METHODS

We derived a frailty index (FI) for 5 cohorts based on the accumulation of deficits approach. Four linear and quadratic growth curve models were fit in each cohort independently. Models were adjusted for sex/gender, age, years of education, and a sex/gender-by-age interaction term.

RESULTS

Models describing linear progression of frailty best fit the data. Annual increases in FI ranged from 0.002 in the Invecchiare in Chianti cohort to 0.009 in the Longitudinal Aging Study Amsterdam (LASA). Women had consistently higher levels of frailty than men in all cohorts, ranging from an increase in the mean FI in women from 0.014 in the Health and Retirement Study cohort to 0.046 in the LASA cohort. However, the associations between sex/gender and rate of frailty progression were mixed. There was significant heterogeneity in within-person trajectories of frailty about the mean curves.

DISCUSSION AND IMPLICATIONS

Our findings of linear longitudinal increases in frailty highlight important avenues for future research. Specifically, we encourage further research to identify potential effect modifiers or groups that would benefit from targeted or personalized interventions.

The relationship between social deprivation and a frailty index of cumulative deficits in French middle-aged caregivers

Background

The Institut Pasteur de Lille, in the north of France, has implemented a large, multidisciplinary health check, which aims to identify frailty in middle-aged caregivers. We aimed to construct an adapted frailty index of cumulative deficit (FI-CD) and study the associated factors, in particular socioeconomic factors.

Methods

The cross-sectional study included caregivers aged 45 to 65. A 34-item FI-CD including deficits adapted to a middle-aged population (related to cognition and autonomy, dietetics, physical activity, comorbidities, functional signs, lab values and paraclinical examinations) was constructed in accordance with standard procedures. It was calculated as a ratio of deficits present out of the total number of possible deficits, giving a continuous score between 0 and 1. Scores > 0.25 and >  0.4 were classified as frailty and severe frailty, respectively. Univariate and multivariate associations were studied using linear regressions.

Results

One hundred and seventeen caregivers were included; among them, 111 were analyzed due to missing values. The mean FI-CD was 0.22 ± 0.08. Forty (36%) individuals were classified as frailty and three (2.7%) as severe frailty. In multivariate analysis, FI-CD was significantly associated with age (beta [95% confidence interval] = 0.005 [0.002; 0.009] per 1-year increase, p = 0.005) and social deprivation (beta = 0.054 [0.007; 0.102], p = 0.025). A significant interaction was observed between and age and social deprivation (p = 0.036). The adjusted relationship between FI-CD and age was beta = 0.010 [0.002; 0.019], p = 0.017 in precarious caregivers, and beta = 0.003 [− 0.001; 0.007], p = 0.19 in non-precarious caregivers.

Conclusions

The study suggested that the 34-item FI-CD could have clinical utility in the management of middle-aged caregivers. Social deprivation appeared as an important factor associated with frailty, highlighting the importance of early care and social support for precarious caregivers.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02736-3.

The conceptual and practical definitions of frailty in older adults: a systematic review

Purpose

This study aimed to review and extract all publications containing concepts related to definitions of frailty and categorize them.

Methods

A total of six electronic databases (PubMed, Ovid web, Web of Science, Scopus, Embase, Cochrane Library, and ProQuest) were searched to identify studies that introduced a definition of frailty up to October 2018. No language restrictions were imposed.

Results

Totally, 104,370 papers were found in the initial search and finally 68 papers were included. Of these, 21 studies provided a conceptual definition and 50 original articles also 9 review articles provided a practical definition. Moreover, 12 papers had both definitions of frailty. Of them, 62 were published in English, 2 in Portuguese, 1 in Japanese, 2 in Korean, and 1 in German languages.

Conclusion

Many screening tools have been developed but neither of them can cover a wide range of parameters at the same time, nor do they have simplicity in the execution. It is important to note that although a more or less general consensus on one single definition might be expected, we believe that the elderly population is too heterogeneous to allow a tool to address it as a whole, and such a definition may even be impossible. Therefore, in the absence of a "Gold Standard" definition, it is suggested to seek accurate knowledge of the strengths and weaknesses of each definition and choose the most appropriate definition and the most effective evaluation tool according to the purpose of the research and the characteristics of the older population.

A Simplified Frailty Index Predicts Mortality in Older Adults in Beijing

Objective

The comprehensive geriatric assessment (CGA) is an integral tool used to identify vulnerable older adults in need of individualized plans to delay the course of diseases and monitor treatment outcomes. We previously developed and validated a 68-item frailty index (FI) based on the CGA in a large, older, Chinese population. However, substantial time is needed to evaluate the 68 items. Therefore, we aimed to develop and validate a simplified FI for use in Chinese older population.

Design

Longitudinal study.

Setting and Participants

Data were drawn from the Beijing Longitudinal Study of Aging. The study was conducted in 2004 with 1808 participants evaluated using the CGA and was followed-up for 13 years. Mortality was recorded at 3, 5, 8, 10, and 13 years intervals.

Measures

27-Item, 50-item, and 68-item frailty indices were investigated. A Cox proportional hazards model and area under the curve of the receiver operating characteristic (AUC-ROC) were calculated to compare mortality predictions.

Results

The FI was positively correlated with age in males (r = 0.174, P <0.001) and females (r = 0.270, P <0.001). The mean baseline FI was 0.225 ± 0.085 (range: 0.04-0.56) as evaluated by the 27-item FI, 0.181 ± 0.117 (range: 0.02-0.62) by the 50-item FI, and 0.167 ± 0.101 (range: 0.02-0.59) by the 68-item FI. Cox regression models showed that mortality was significantly higher in frail people than in non-frail people for all 3 indices (p<0.001). The AUCs of the 68-item FI, 50-item FI, and 27-item FI for predicting mortality were 0.720, 0.717, and 0.677, respectively (p<0.001).

Conclusion

The 27-item FI is reasonable to expect that the AUC of the indices with the higher items number is inferior to the performance of the indices with higher number of items (FI50 and FI68). But 27-item maybe used as a tool to identify frail older adults and predict mortality in clinical and primary care practices in China.

Symptoms of depression, anxiety, and perceived mastery in older adults before and during the COVID-19 pandemic: Results from the Longitudinal Aging Study Amsterdam

OBJECTIVE

Governmental measures to protect older adults from COVID-19 are hypothesized to cause anxiety and depression. Previous studies are heterogeneous and showed small effects. This study aims to assess depressive and anxiety symptoms and perceived mastery just after the first wave of the COVID-19 pandemic compared to previous years in community-dwelling older adults and to identify potential risk groups according to the comprehensive geriatric assessment framework.

METHODS

Data were used from 1068 Dutch older adults (aged 55-93 at baseline in 2011-2013) participating in the Longitudinal Aging Study Amsterdam, including 4 follow-ups spanning 9 years. Depressive symptoms, anxiety symptoms and feelings of mastery were assessed with the short Center for Epidemiologic Studies Depression scale (CES-D-10), the Hospital Anxiety Depression Scale - Anxiety subscale (HADS-A) and the Pearlin Mastery Scale. Linear mixed regression was used to compare outcomes in June-August 2020 to previous years and to examine predictors to identify risk groups.

RESULTS

Slight increases in CES-D-10 (1.37, 95% Confidence interval [CI] 1.12;1.62), HADS-A (0.74, 95% CI 0.56;0.94) and mastery (1.10, 95% CI 0.88;1.31) occurred during the COVID year compared to previous years. Older adults with functional limitations or with frailty showed a smaller increase in feelings of mastery in the COVID-year.

CONCLUSION

Our results suggest limited mental health effects on older adults from the first COVID-19 wave. Older adults have perhaps better coping strategies than younger adults, or preventive measures did not have extensive consequences for the daily life of older adults. Further monitoring of depression, anxiety and perceived mastery is recommended.

Respiratory Symptoms Are Associated With Frailty in Older Adults With Normal Spirometry, Independent of Smoking, in the Canadian Longitudinal Study of Aging

BACKGROUND

Recent studies have demonstrated that even in the absence of lung impairment as determined by spirometry, smoking and respiratory symptoms are associated with poor overall health and well-being. However, this relationship is not well defined; and it remains unclear the degree to which symptoms are related to poor health, independent of smoking. This is of particular importance to older adults, as they are more likely to exhibit respiratory symptoms and are, therefore, at risk of not receiving appropriate treatment if they have never smoked and have normal spirometry.

METHODS

We performed a cross-sectional analysis of data from the Canadian Longitudinal Study on Aging to delineate the associations of respiratory symptoms and smoking on the health of participants age 45-86 who exhibited normal spirometry. Participant health was estimated using a frailty index, a multidimensional measure of vulnerability to adverse outcomes that has been validated in numerous health settings.

RESULTS

Of the 21,293 participants included in our analysis, 87% exhibited a normal FEV₁, FVC, and FEV₁/FVC; of those, 45% reported at least one respiratory symptom, and 50% were former or current smokers. Both respiratory symptoms and smoking were independently associated with frailty (median interquartile range [IQR] = 0.11 [0.07-0.15]), the most substantial associations observed for those having at least one respiratory symptom (adjusted β 0.023, 95% CI 0.022-0.025) and current smokers with > 10 pack-year exposure (adjusted β 0.014, 95% CI [0.010-0.019). Not only was the association between symptoms and frailty evident in never smokers, a significant proportion of the total effect of smoking on frailty was observed to be mediated by symptoms.

CONCLUSIONS

Our data show that respiratory symptoms, regardless of smoking history, were a significant correlate of frailty in older adults with normal spirometry. Hence, they should not be simply regarded as a benign by-product of aging.

Validation of a Deficit-Accumulation Frailty Index in the ASPirin in Reducing Events in the Elderly Study and Its Predictive Capacity for Disability-Free Survival

Frailty is a state of heightened vulnerability and susceptibility to physiologic stressors that increases with age. It has shown increasing utility in predicting a range of adverse health outcomes. Here, we characterize a 67-item deficit-accumulation frailty index (FI) in 19 110 community-dwelling individuals in the ASPirin in Reducing Events in the Elderly clinical trial. Participants aged 65-98 years were recruited from the United States and Australia and were without diagnosed dementia and cardiovascular disease, and major physical disability. The median FI score was .10 (interquartile range: .07-.14) at baseline, and the prevalence of frailty (FI > .21) increased from 8.1% to 17.4% after 6 years. FI was positively associated with age, and women had significantly higher scores than men at all ages. The FI was negatively correlated with gait speed (r = -.31) and grip strength (r = -.46), and strongly associated with a modified Fried's frailty phenotype (p < .0001, for all comparisons). Frailty was associated with the primary composite outcome capturing independent life lived free of major disability and dementia, and increased the rate of persistent physical disability (hazard ratio: 21.3, 95% confidence interval: 15.6-28.9). It added significantly to the predictive capacity of these outcomes above age, sex, and ethnicity alone. The FI is thus a useful biomarker of aging even among relatively healthy older individuals and provides important information about an individual's vulnerability to and risk of disease.

Trends in Frailty and Its Association With Mortality: Results From the Longitudinal Aging Study Amsterdam, 1995-2016

The aim of this study was to investigate trends in frailty and its relationship with mortality among older adults aged 64–84 years across a period of 21 years. We used data from 1995 to 2016 from the Longitudinal Aging Study Amsterdam. A total of 7,742 observations of 2,874 respondents in the same age range (64–84 years) across 6 measurement waves were included. Frailty was measured with a 32-item frailty index, with a cutpoint of ≥0.25 to indicate frailty. The outcome measure was 4-year mortality. Generalized estimating equation analyses showed that among older adults aged 64–84 years the 4-year mortality rate declined between 1995 and 2016, while the prevalence of frailty increased. Across all measurement waves, frailty was associated with 4-year mortality (odds ratio = 2.79, 95% confidence interval: 2.39, 3.26). There was no statistically significant interaction effect between frailty and time on 4-year mortality, indicating a stable association between frailty and mortality. In more recent generations of older adults, frailty prevalence rates were higher, while excess mortality rates of frailty remained the same. This is important information for health policy-makers and clinical practitioners, showing that continued efforts are needed to reduce frailty and its negative health consequences.

Older adults report cancellation or avoidance of medical care during the COVID-19 pandemic: results from the Longitudinal Aging Study Amsterdam

Aim

To investigate the extent to which Dutch older adults reported cancellation or avoidance of medical care during the first months of the COVID-19 pandemic.

Findings

One third of the study sample reported cancellation or avoidance of medical care during the first months of the pandemic, and this was more common among those with multiple chronic conditions.

Message

Delay of routine care during the pandemic may impact morbidity and related adverse outcomes in the long term, which should be monitored in future research.

Purpose

Delay of routine medical care during the COVID-19 pandemic may have serious consequences for the health and functioning of older adults. The aim of this study was to investigate whether older adults reported cancellation or avoidance of medical care during the first months of the COVID-19 pandemic, and to explore associations with health and socio-demographic characteristics.

Methods

Cross-sectional data of 880 older adults aged ≥ 62 years (mean age 73.4 years, 50.3% female) were used from the COVID-19 questionnaire of the Longitudinal Aging Study Amsterdam, a cohort study among community-dwelling older adults in the Netherlands. Cancellation and avoidance of care were assessed by self-report, and covered questions on cancellation of primary care (general practitioner), cancellation of hospital outpatient care, and postponed help-seeking. Respondent characteristics included age, sex, educational level, loneliness, depression, anxiety, frailty, multimorbidity and information on quarantine.

Results

35% of the sample reported cancellations due to the COVID-19 situation, either initiated by the respondent (12%) or by healthcare professionals (29%). Postponed help-seeking was reported by 8% of the sample. Multimorbidity was associated with healthcare-initiated cancellations (primary care OR = 1.92, 95% CI = 1.09–3.50; hospital OR = 1.86, 95% CI = 1.28–2.74) and respondent-initiated hospital outpatient cancellations (OR = 2.02, 95% CI = 1.04–4.12). Depressive symptoms were associated with postponed help-seeking (OR = 1.15, 95% CI = 1.06–1.24).

Conclusion

About one third of the study sample reported cancellation or avoidance of medical care during the first months of the pandemic, and this was more common among those with multiple chronic conditions. How this impacts outcomes in the long term should be investigated in future research.

Multiple domains of functioning in older adults during the pandemic: design and basic characteristics of the Longitudinal Aging Study Amsterdam COVID-19 questionnaire

The Longitudinal Aging Study Amsterdam (LASA) is an ongoing cohort study among older adults in the Netherlands. Respondents are usually interviewed approximately every 3 years. Because of the exceptional situation of the COVID-19 pandemic, it was decided to add an extra assessment in between, consisting of a postal/digital questionnaire with measures assessing the impact of the COVID-19 situation, as well as a selection of measures from regular LASA measurement cycles covering the physical, social and mental domains. In total, 1128 LASA respondents aged 62-102 years provided data, just after the first wave of the pandemic in 2020. This paper describes the methods and design of the LASA COVID-19 questionnaire, as well as the basic characteristics of the sample, including an overview of impactful situations experienced by older adults during the first months of the pandemic. The data of the questionnaire may be used to study the impact of the COVID-19 pandemic on multiple domains of functioning in older adults.

Acceleration of health deficit accumulation in late-life: evidence of terminal decline in frailty index three years before death in the US Health and Retirement Study

BACKGROUND

Little is known about within-person frailty index (FI) changes during the last years of life. In this study, we assess whether there is a phase of accelerated health deficit accumulation (terminal health decline) in late-life.

MATERIAL AND METHODS

A total of 23,393 observations from up to the last 21 years of life of 5713 deceased participants of the AHEAD cohort in the Health and Retirement Study were assessed. A FI with 32 health deficits was calculated for up to 10 successive biannual, self- and proxy-reported assessments (1995-2014), and FI changes according to time-to-death were analyzed with a piecewise linear mixed model with random change points.

RESULTS

The average normal (preterminal) health deficit accumulation rate was 0.01 per year, which increased to 0.05 per year at approximately 3 years before death. Terminal decline began earlier in women and was steeper among men. The accelerated (terminal) rate of health deficit accumulation began at a FI-value of 0.29 in the total sample, 0.27 for men, and 0.30 for women.

CONCLUSION

We found evidence for an observable terminal health decline in the FI following declining physiological reserves and failing repair mechanisms. Our results suggest a conceptually meaningful cut-off value for the continuous FI around 0.30.

Operationalization of a frailty index in patients with multiple sclerosis: A cross-sectional investigation

BACKGROUND

Frailty is an age-related status of increased vulnerability to stressors caused by the accumulation of multiple health deficits. This construct may allow to capture the clinical complexity of patients with multiple sclerosis (MS).

OBJECTIVE

To investigate the relationship between frailty and the clinical manifestations of MS.

METHODS

Patients with MS were consecutively enrolled at five tertiary dedicated services. Disability and fatigue were assessed. The phenotypes of MS were also identified. Frailty was measured using a frailty index (FI), computed by cumulatively considering 42 age-related multidimensional health deficits.

RESULTS

Overall, 745 MS patients (mean age = 48.2 years, standard deviation = 11.7 years; women 68%) were considered. The median FI value was 0.12 (interquartile range = 0.05-0.19) and the 99th percentile was 0.40. FI scores were associated with MS disease duration, disability, fatigue, as well as with the number of previous disease-modifying treatments and current symptomatic therapies. A logistic regression analysis model showed that FI score was independently associated with the secondary progressive phenotype.

CONCLUSION

Frailty is significantly associated with major characteristics of MS. The findings of the present cross-sectional investigation should be explored in future longitudinal studies.

Course of frailty stratified by physical and mental multimorbidity patterns: a 5-year follow-up of 92,640 participants of the LifeLines cohort study

BACKGROUND

The frailty index (FI) is a well-recognized measurement for risk stratification in older people. Among middle-aged and older people, we examined the prospective association between the FI and mortality as well as its course over time in relation to multimorbidity and specific disease clusters.

METHODS

A frailty index (FI) was constructed based on either 64 (baseline only) or 35 health deficits (baseline and follow-up) among people aged ≥ 40 years who participated in LifeLines, a prospective population-based cohort living in the Northern Netherlands. Among 92,640 participants, multivariable Cox proportional hazard models were fitted to study the hazard ratio (HR) of the FI at baseline, as well as for 10 chronic disease clusters for all-cause mortality over a 10-year follow-up. Among 55,426 participants, linear regression analyses were applied to study the impact of multimorbidity and of specific chronic disease clusters (independent variables) on the change of frailty over a 5-year follow-up, adjusted for demographic and lifestyle characteristics.

RESULTS

The FI predicted mortality independent of multimorbidity and specific disease clusters, with the highest impact in people with either endocrine, lung, or heart diseases. Adjusted for demographic and lifestyle characteristics, all chronic disease clusters remained independently associated with an accelerated increase of frailty over time.

CONCLUSIONS

Frailty may be seen as a final common pathway for premature death due to chronic diseases. Our results suggest that initiating frailty prevention at middle age, when the first chronic diseases emerge, might be relevant from a public health perspective.

Using elastic nets to estimate frailty burden from routinely collected national aged care data

OBJECTIVES

To (1) use an elastic net (EN) algorithm to derive a frailty measure from a national aged care eligibility assessment program; (2) compare the ability of EN-based and a traditional cumulative deficit (CD) based frailty measures to predict mortality and entry into permanent residential care; (3) assess if the predictive ability can be improved by using weighted frailty measures.

MATERIALS AND METHODS

A Cox proportional hazard model based EN algorithm was applied to the 2003-2013 cohort of 903 996 participants for selecting items to enter an EN based frailty measure. The out-of-sample predictive accuracy was measured by the area under the curve (AUC) from Cox models fitted to 80% training and validated on 20% testing samples.

RESULTS

The EN approach resulted in a 178-item frailty measure including items excluded from the 44-item CD-based measure. The EN based measure was not statistically significantly different from the CD-based approach in terms of predicting mortality (AUC 0.641, 95% CI: 0.637-0.644 vs AUC 0.637, 95% CI: 0.634-0.641) and permanent care entry (AUC 0.626, 95% CI: 0.624-0.629 vs AUC 0.627, 95% CI: 0.625-0.63). However, the weighted EN based measure statistically outperforms the weighted CD measure for predicting mortality (AUC 0.774, 95% CI: 0.771-0.777 vs AUC 0.757, 95% CI: 0.754-0.760) and permanent care entry (AUC 0.676, 95% CI: 0.673-0.678 vs AUC 0.671, 95% CI: 0.668-0.674).

CONCLUSIONS

The weighted EN and CD-based measures demonstrated similar prediction performance. The CD-based measure items are relevant to frailty measurement and easier to interpret. We recommend using the weighted and unweighted CD-based frailty measures.

Predictors of Frailty and Vitality in Older Adults Aged 75 years and Over: Results from the Longitudinal Aging Study Amsterdam

INTRODUCTION

Frailty can be seen as a continuum, from fit to frail. While many recent studies have focused on frailty, much less attention has been paid to the other end of the continuum: the group of older adults that remain (relatively) vital. Moreover, there is a lack of studies on frailty and vitality that investigate predictors from multiple domains of functioning simultaneously. The aim of this study was to identify predictors of frailty as well as vitality among older adults aged 75 years and over.

METHODS

We used longitudinal data from 569 adults aged ≥75 years who participated in the Longitudinal Aging Study Amsterdam. Predictors from the sociodemographic, social, psychological, lifestyle, and physical domains of functioning were measured at T1 (2008-2009). We used the frailty index (FI) to identify frail (FI ≥ 0.25) and vital (FI ≤ 0.15) respondents at follow-up, 3 years later (T2: 2011-2012). We conducted logistic regression analyses with backward stepwise selection to develop and internally validate our prediction models.

RESULTS

The prevalence of frailty in our sample at follow-up was 49.4% and the prevalence of vitality was 18.3%. Predictors of frailty and vitality partly overlapped and included age, depressive symptoms, number of chronic diseases, and self-rated health. We also found predictors that did not overlap. Male sex, moderate alcohol use, more emotional support received, and no hearing problems, were predictors of vitality. Lower cognitive functioning, polypharmacy, and pain were predictors of frailty. The final model for vitality explained 42% of the variance and the final model for frailty explained 48%. Both models had a good discriminative value (area under ROC-curve [AUC] vitality: 0.88; AUC frailty: 0.85).

CONCLUSION

Among older adults aged 75 years and over, predictors of frailty only partially overlap with predictors of vitality. The readily accessible predictors in our models may help to identify older adults who are likely to be vital, or who are at risk of frailty.

Inflammation as a risk factor for the development of frailty in the Lothian Birth Cohort 1936

Background

Research suggests that frailty is associated with higher inflammation levels. We investigated the longitudinal association between chronic inflammation and frailty progression.

Methods

Participants of the Lothian Birth Cohort 1936, aged 70 at baseline were tested four times over 12 years (wave 1: n = 1091, wave 4: n = 550). Frailty was assessed by; the Frailty Index at waves 1–4 and Fried phenotype at waves 1, 3 and 4. Two blood-based inflammatory biomarkers were measured at wave 1: Fibrinogen and C-reactive protein (CRP).

Results

Fully-adjusted, linear mixed effects models showed higher Fibrinogen was significantly associated with higher wave 1 Frailty Index score (β = 0.011, 95% CI[0.002,0.020], p < .05). Over 12 year follow-up, higher wave 1 CRP (β = 0.001, 95% CI[0.000,0.002], p < .05) and Fibrinogen (β = 0.004, 95% CI[0.001,0.007], p < .05) were significantly associated with increased Frailty Index change. For the Fried phenotype, wave 1 Pre-frail and Frail participants had higher CRP and Fibrinogen than Non-frail participants (p < .001). Logistic regression models calculated risk of worsening frailty over follow-up and we observed no significant association of CRP or Fibrinogen in minimally-adjusted nor fully-adjusted models.

Conclusions

Findings showed a longitudinal association of higher wave 1 CRP and Fibrinogen on worsening frailty in the Frailty Index, but not Fried Phenotype. A possible explanation for this disparity may lie in the conceptual differences between frailty measures (a biopsychosocial vs physical approach). Future research, which further explores different domains of frailty, as well the associations between improving frailty and inflammation levels, may elucidate the pathway through which inflammation influences frailty progression. This may improve earlier identification of those at high frailty risk.

•

Research exploring inflammation and frailty change over time is lacking.

•

Inflammation is associated with frailty over time when measured by a Frailty Index.

•

Understanding this association may help improve frailty interventions.

•

Results differ according to the tool used to measure frailty.

•

Future research should continue to compare different ways of measuring frailty.

Age and life expectancy clocks based on machine learning analysis of mouse frailty

The identification of genes and interventions that slow or reverse aging is hampered by the lack of non-invasive metrics that can predict the life expectancy of pre-clinical models. Frailty Indices (FIs) in mice are composite measures of health that are cost-effective and non-invasive, but whether they can accurately predict health and lifespan is not known. Here, mouse FIs are scored longitudinally until death and machine learning is employed to develop two clocks. A random forest regression is trained on FI components for chronological age to generate the FRIGHT (Frailty Inferred Geriatric Health Timeline) clock, a strong predictor of chronological age. A second model is trained on remaining lifespan to generate the AFRAID (Analysis of Frailty and Death) clock, which accurately predicts life expectancy and the efficacy of a lifespan-extending intervention up to a year in advance. Adoption of these clocks should accelerate the identification of longevity genes and aging interventions.