Frailty Index as a Measure of Biological Age in a Chinese Population

Gut microbial features and circulating metabolomic signatures of frailty in older adults

Frailty, a multidimensional indicator of suboptimal aging, reflects cumulative declines across multiple physiological systems. Although age-related changes have been reported in gut microbiota, their role in healthy aging remains unclear. In this study, we calculated frailty index (FI) from 33 health-related items to reflect the overall health status of 1,821 older adults (62-96 years, 55% female) and conducted multi-omics analysis using gut metagenomic sequencing data and plasma metabolomic data. We identified 18 microbial species and 17 metabolites shifted along with frailty severity, with stronger links observed in females. The associations of nine species, including various Clostridium species and Faecalibacterium prausnitzii, with FI were reproducible in two external populations. Plasma glycerol levels, white blood cell count and kidney function partially mediated these associations. A composite microbial score derived from FI significantly predicted 2-year mortality (adjusted hazard ratio across extreme quartiles, 2.86; 95% confidence interval, 1.38-5.93), highlighting the potential of microbiota-based strategies for risk stratification in older adults.

Associations of Dietary Diversity Trajectories with Frailty among Chinese Older Adults: A Latent Class Trajectory Analysis Based on a CLHLS Cohort

BACKGROUND

High dietary diversity has been found to be associated with frailty. However, the trajectory of dietary diversity intake in relation to frailty is unclear.

METHODS

Using the latent class trajectory modeling approach, we identified distinctive dietary variety trajectory groups among 2017 participants based on the Chinese Longitudinal Healthy Longevity Survey acquired at four time points within a 10-year period. Frailty status was assessed using a frailty index comprising 37 health deficits. Dietary diversity was quantified using the dietary variety score (DVS), based on food category consumption frequency. Logistic regression analyses were employed to explore the association between DVS change trajectories and frailty.

RESULTS

This study identified two distinct DVS trajectories: "Moderate-Slow decline-Slow growth", encompassing 810 (40.16%) individuals, and "Moderate-Slow growth-Accelerated decline", including 1207 (59.84%) individuals. After adjusting for covariates, the odds ratio for DVS in the "Moderate-Slow decline-Slow growth" group was 1.326 (95% confidence interval: 1.075-1.636) compared to the "Moderate-Slow growth-Accelerated decline" group. The "Moderate-Slow decline-Slow growth" trajectory continued to decrease and was maintained at a low level in the early stages of aging.

CONCLUSION

Sustaining a high dietary diversity trajectory over time, particularly in the early stages of aging, could potentially decrease the risk of frailty among older Chinese adults.

Unveiling the multifaceted nexus of subjective aging, biological aging, and chronological age: Findings from a nationally representative cohort study

OBJECTIVES

This study aims to investigate how subjective aging influences the psychological and behavioral responses of older individuals, specifically focusing on the associations between subjective aging and longitudinal changes in biological age.

METHODS

This is a retrospective cohort study retrieving data from the Taiwan Longitudinal Study on Aging (TLSA), over a 4-year follow-up period. Subjective aging is assessed by asking participants if they perceive themselves as old, while frailty is measured using a frailty index comprising 34 deficits from various domains. Participants are categorized into three groups based on their chronological age. The association between subjective aging and transition of biological age (as indicated by an increased frailty index) from 2011 to 2015 is examined using logistic regression models.

RESULTS

The study consisted of 2412 participants, who were categorized into middle-age (n = 1,082), young-old (n = 779), and old-old (n = 551) groups. Among them, individuals exhibiting subjective aging at baseline were more likely to be older in chronological age, female, illiterate, and unemployed, compared to those without subjective aging. The adjusted odds ratios (aORs) for the association between subjective aging and an increased biological age were 1.72 [95% CI: 0.88-3.34], 1.61 [0.77-3.37], and 1.08 [0.65-1.80], in the middle-age, young-old, and old-old groups, respectively.

DISCUSSIONS

No significant associations were found between changes in biological age and subjective aging across various chronological age groups. Notably, within the younger age group, a discernible trend towards an association was observed, indicating the potential age-related nuances in the complex interrelation between subjective age, biological aging, and chronological aging.

Links between life-course SES and frailty trajectory moderated by community environment resources: Person-environment Fit perspective

INTRODUCTION

Drawing from the life course and person-environment fit perspectives, this study examined whether life-course SES disadvantages during childhood, adulthood and old- age influence frailty development in late- life and how community environment resources moderated the association between life-course SES disadvantages and frailty trajectories over a seven-year follow-up period.

METHODS

Data from 11,675 participants aged ≥ 50 years at baseline who participated in the four waves (2011-2018) of the China Health and Retirement Longitudinal Survey (CHARLS) were used. Life-course SES disadvantages were self-reported, and community environment resources (basic infrastructure and voluntary organizations) were ascertained from informed officials in the community. Frailty development was measured at each wave by the Frailty Index (FI) based on 39 potential deficits. Multilevel growth modeling was used to examine the interactive effect of life-course SES disadvantages and community environment resources on frailty development.

RESULTS

Life-course SES disadvantage exerted cumulatively negative effects on frailty trajectory, and individuals with SES disadvantages in two or three life stages reported higher initial levels of and faster increases in frailty scores. Community environmental resources (basic infrastructure and voluntary organizations) had a protective effect on frailty development and buffered the negative effects of SES vulnerability experiences accumulated over the life course. Community basic infrastructure resources played an important role in slowing the progression of frailty for individuals with cumulative SES disadvantage and downward mobility.

DISCUSSION

Our findings provided new evidence of person-environmental docility among older adults, documenting the role of community resources in buffering SES disparities in health during later-life.

Marital transitions and frailty among middle-aged and older adults in China: The roles of social support

Background

This study explored the association of marital transitions and frailty among Chinese middle-aged and older people and whether this association differs by social support.

Methods

We used a sample of 12,388 adults aged ≥45 years who participated in the China Health and Retirement Longitudinal Study (CHARLS) between 2015 and 2018. Between-wave changes in marital status ("married at both times", "unmarried to married", "married to unmarried", "unmarried at both times") were used to explore the changes in frailty measured by the frailty index (FI), which was constructed from 55 health variables. Social support was evaluated based on social engagement and intergenerational support. The associations among marital transitions, social support and frailty were analyzed using generalized estimating equations (GEEs).

Results

The mean FI of 12,388 participants was 0.23 (SD = 0.13). Participants who were married to unmarried (β = 0.014, B = 0.005, P = 0.012) and unmarried at both times (β = 0.022, B = 0.003, P < 0.001) had significant a positive impact on FI compared with participants who were married at both times. Social engagement, financial support by children and providing care to grandchildren had an interactive effect with marital transitions in influencing FI.

Conclusions

Being unmarried may increase frailty among Chinese middle-aged and older adults. Financial support by children may mitigate the adverse effects of being unmarried on frailty.

Discordant Biological and Chronological Age: Implications for Cognitive Decline and Frailty

BACKGROUND

Older adults with discordant biological and chronological ages (BA and CA) may vary in cognitive and physical function from those with concordant BA and CA.

METHODS

To make our approach clinically accessible, we created easy-to-interpret participant groups in the Health, Aging, and Body Composition Study (N = 2 458, 52% female participants, 65% White participants, age: 73.5 ± 2.8) based on medians of CA, and a previously validated BA index comprised of readily available clinical tests. Joint models estimated associations of BA-CA group with cognition (Modified Mini-Mental State Examination [3MS] and Digit Symbol Substitution Test [DSST]) and frailty over 10 years.

RESULTS

The sample included the following: 32%, Young group (BA and CA < median); 21%, Prematurely Aging group (BA ≥ median, CA < median), 27%, Old group (BA and CA ≥ median), and 20%, Resilient group (BA < median, CA ≥ median). In education-adjusted models of cognition, among those with CA < median, the Prematurely Aging group performed worse than the Young at baseline (3MS and DSST p < .0001), but among those with CA ≥ median, the Resilient group did not outperform the Old group (3MS p = .31; DSST p = .25). For frailty, the Prematurely Aging group performed worse than the Young group at baseline (p = .0001), and the Resilient group outperformed the Old group (p = .003). For all outcomes, groups did not differ on change over time based on the same pairwise comparisons (p ≥ .40).

CONCLUSIONS

Discordant BA and CA identify groups who have greater cognitive and physical functional decline or are more protected than their CA would suggest. This information can be used for risk stratification.

Prevalence and factors associated with frailty and pre-frailty in the older adults in China: a national cross-sectional study

Objective

Frailty increases poor clinical outcomes in older adults, the aim of this study was to investigate the prevalence and factors associated with frailty and pre-frailty in older adults in China.

Research design and methods

Data were obtained from the Sample Survey of the Aged Population in Urban and Rural China in 2015, which was a cross-sectional study involving a nationally representative sample of older adults aged 60 years or older from 31 provinces/autonomous regions/municipalities in mainland China. The frailty index (FI) based on 33 potential deficits was used to classify individuals as robust (FI < 0.12), pre-frail (FI ≧0.12 and <0.25) and frail (FI ≥0.25).

Results

A total of 208,386 older people were included in the study, and the age-sex standardised prevalence of frailty and pre-frailty among older adults in China was 9.5% (95% CI 9.4-9.7) and 46.1% (45.9-46.3) respectively. The prevalence of frailty and pre-frailty was higher in female than in male older adults, higher in rural than in urban older adults, and higher in northern China than in southern China. The multinomial analysis revealed similar risk factors for frailty and pre-frailty, including increased age, being female, living in a rural area, low educational attainment, poor marital status, living alone, difficult financial status, poor access to medical reimbursement, and living in northern China.

Conclusion

Frailty and pre-frailty are very common among older adults in China and differ significantly between southern and northern China, men and women, and rural and urban areas. Appropriate public health prevention strategies should be developed based on identified risk factors in frail and pre-frail populations. The management of frailty and pre-frailty should be optimised according to regional and gender differences in prevalence and associated factors, such as strengthening the integrated management of chronic diseases, increasing reimbursement rates for medical costs, and focusing on vulnerable groups such as the disabled, economically disadvantaged, living alone and those with low literacy levels, in order to reduce the burden of frailty among older adults in China.

Spatial variations and influencing factors of Cumulative Health Deficit Index of elderly in China

BACKGROUND

With the acceleration of aging and urbanization, how to make cities more age-friendly has become a hot topic. During the long-term demographic transition, the health of the elderly has become an important consideration in urban planning and management. The health of the elderly is a complex issue. However, previous studies have mainly focused on the health defects related to disease incidence, loss of function, mortality, etc., yet a comprehensive evaluation of health status is lacking. The Cumulative Health Deficit Index (CHDI) is a composite index that combines psychological and physiological indicators. Health deficits can reduce the quality of life of the elderly and increase the burden on families, cities and even society, so it is indispensable to understand the individual factors and regional factors that affect CHDI. The research on the spatial differentiation of CHDI and its driving factors can provide scientific geographic information basis for the construction of age-friendly cities and healthy city planning. It also has great significance in narrowing the differences in the health status among regions and reducing the overall burden of the country.

METHODS

This research analyzed a nationwide dataset, the China Longitudinal Aging Social Survey in 2018 conducted by the Renmin University of China, which contained 11,418 elderly aged 60 years and older from 28 provinces/municipalities/autonomous regions that represent 95% of the population in mainland China. The Cumulative Health Deficit Index (CHDI) was the first time constructed using the entropy-TOPSIS method to evaluate the health status of the elderly. Entropy-TOPSIS is to quantify the importance of each indicator by calculating the entropy value to improve the reliability and accuracy of the results and avoid the influence of previous researchers' subjective assignments and model assumptions on the results. The selected variables include physical health 27 indicators (self-rated health, basic mobility assessment, daily activity ability, disease and treatment) and mental health 36 indicators (cognitive ability, depression and loneliness, social adjustment, and filial piety concept). The research used the Geodetector methods (factor detection and interaction detection) that combined individual and regional indicators to analyze the spatial variation characters and reveal the driving factors of CHDI.

RESULTS

The weight of mental health indicators (75.73) is three times that of physical health indicators (24.27), and its composition formula is: CHDI value = (14.77% disease and treatment + 5.54% daily activity ability + 2.14% health self-assessment + 1.81% basic mobility assessment) + (33.37% depression and loneliness + 25.21% cognitive ability + 12.46% social adjustment + 4.7% filial piety). Individual CHDI was more associated with age and was more evident in females than males. CHDI average values show the distribution trend of Hu Line (HL) in the geographic information graph that the CHDI in West HL regions are lower than in the East HL regions. The highest CHDI cities are in Shanxi, Jiangsu, and Hubei, whereas the lowest CHDI cities are Inner Mongolia, Hunan and Anhui. The geographical distribution maps of the 5-levels of CHDI levels show very different CHDI classification levels among the elderly in the same region. Further, the top three influential factors are personal income, empty nest, aged 80+, and regional factors also obviously affect CHDI values, such as the proportion participating in insurance, population density, and GDP. The two different factors in individual and regional factors all show a two-factor interaction effect, and enhancement or nonlinear enhancement. The top three ranks are personal income ∩ quality of air (0.94), personal income ∩ GDP (0.94), and personal income ∩ urbanization rate (0.87).

CONCLUSIONS

CHDI is a subjective and objective comprehensive index, and mental indicators are primary factors. Thus attaching importance to the psychological care of the elderly is the key to building a healthy aging society. The large individual heterogeneity and spatial differentiation of CHDI in the elderly were demonstrated by map visualization. The analysis of the influencing factors of CHDI by the Geodetector method proves that spatial differentiation is mainly affected by individual economic and social security factors, but also by the interaction with regional factors such as quality of air, GDP, and urbanization rate. This research fills a gap in the elderly health status in the field of spatial geography. The results can provide empirical evidence for policymakers to take measures according to local conditions to improve the health status of the elderly according to regional differences in physical and mental conditions. It also plays a guiding role for the country in balancing regional economic development, promoting healthy and sustainable urban development, and creating age-friendly cities.

From MIA to FIFA: The vicious matrix of frailty, inflammation, fluid overload and atherosclerosis in peritoneal dialysis

Cardiovascular disease (CVD) is a major cause of mortality and morbidity in peritoneal dialysis (PD) patients. Two decades ago, the common co-existence of malnutrition and systemic inflammation PD patients with atherosclerosis and CVD led to the proposed terminology of 'malnutrition-inflammation-atherosclerosis (MIA) syndrome'. Although the importance of malnutrition is well accepted, frailty represents a more comprehensive assessment of the physical and functional capability of the patient and encompasses the contributions of sarcopenia (a key component of malnutrition), obesity, cardiopulmonary as well as neuropsychiatric impairment. In recent years, it is also increasingly recognized that fluid overload is not only the consequence but also play an important role in the pathogenesis of CVD. Moreover, fluid overload is closely linked with the systemic inflammatory status, presumably by gut oedema, gastrointestinal epithelial barrier dysfunction and leakage of bacterial fragments to the systemic circulation. There are now a wealth of published evidence to show intricate relations between frailty, inflammation, fluid overload and atherosclerotic disease in patients with chronic kidney disease (CKD) and those on PD, a phenomenon that we propose the term 'FIFA complex'. In this system, frailty and atherosclerotic disease may be regarded as two patient-oriented outcomes, while inflammation and fluid overload are two inter-connected pathogenic processes. However, there remain limited data on how the treatment of one component affect the others. It is also important to define how treatment of fluid overload affect the systemic inflammatory status and to develop effective anti-inflammatory strategies that could alleviate atherosclerotic disease and frailty.

Effect of frailty status on mortality risk among Chinese community-dwelling older adults: a prospective cohort study

BACKGROUND

Frailty is associated with mortality among older adults. We aimed to determine the appropriate time and frailty index (FI) threshold for frailty intervention in Chinese community-dwelling older adults.

METHODS

In this prospective cohort study, we used data from the 2011 wave of the Chinese Longitudinal Healthy Longevity Study. Follow-up was performed for seven years from baseline. Using the FI to evaluate frailty and define frailty status, we explored the best time point and FI score for frailty intervention, by comparing the relationships of FI and frailty status with mortality.

RESULTS

From 2011 to 2018, 8642 participants were included and followed-up. A total of 4458 participants died during the study period. After adjusting for variables such as age, sex, marital status, education level, and living conditions, the hazard ratio (HR) of mortality risk based on the FI at baseline was 37.484 (95% confidence interval [CI]: 30.217-46.498; P < 0.001); female sex, living in the city, being married, and living with spouse were found to be protective factors, whereas ageing was a risk factor for frailty. The mortality risk was higher in pre-frail than in frail participants (HR: 3.588, 95% CI: 3.212-4.009, P < 0.001). Piecewise linear regression analysis revealed an FI score threshold of 0.5. When the FI score was > 0.5, the HR of mortality based on the FI was 15.758 (95% CI: 3.656-67.924; P < 0.001); when the FI score was ≤ 0.5, the HR of mortality based on the FI was 48.944 (95% CI: 36.162-66.244; P < 0.001).

CONCLUSION

Using FI as a continuous variable to predict death is more accurate than frailty status. The advancement of early interventions for mortality risk reduction is more beneficial in pre-frail than in frail patients, and an FI score of 0.5 was found to be the threshold for mortality prediction using the FI.

Effects of dietary diversity on frailty in Chinese older adults: a 3-year cohort study

BACKGROUND

Frailty has emerged as a global health burden with increased population aging. A diverse diet is essential for an adequate and balanced supply of nutrients. However, limited evidence supports the relationship between dietary diversity and frailty. We therefore assessed the associations of dietary diversity with the risk of frailty.

METHODS

We used the Chinese Longitudinal Healthy Longevity Survey to analyze a prospective cohort of Chinese older adults. A total of 1948 non-frail older adults were included in the final sample. Participants were categorized into groups with high or low dietary diversity scores (DDSs) using a food frequency questionnaire. A Generalized Estimating Equation were used to estimate risk ratios (RRs) and 95% confidence intervals (CIs) for determining frailty incidence.

RESULTS

Among 1,948 participants, 381 had frailty with the prevalence of 19.56% during the 3-year follow-up period. Compared with the low DDS group, the high DDS group exhibited a lower risk of frailty (RR, 0.72; 95% CI: 0.57-0.91). Compared with those with a consistently low DDS, the RR of participants with a consistently high DDS for frailty was 0.56 (95% CI: 0.42-0.74). Moreover, meat, beans, fish, nuts, fresh fruits, and fresh vegetables were inversely associated with frailty. In stratified analysis, a consistently high DDS, compared with a consistently low DDS, reduced the risk of frailty for people aged 65-79 years and those living in town and rural areas.

CONCLUSION

This study found a prospective association between dietary diversity and frailty among Chinese older adults. These findings stressed that it is important to improve dietary diversity for older adults to promote healthy ageing, particularly for young older adults and in town and rural areas.

Severity of frailty using modified Thai frailty index, social factors, and prediction of mortality among community-dwelling older adults in a middle-income country

Background

Frailty has been increasingly recognized as a public health problem for aging populations with significant social impact, particularly in low- and middle-income countries. We aimed to develop a modified version of the Thai Frailty Index (TFI) and explore the association between different frailty statuses, socioeconomic factors, and mortality in community-dwelling older people from a middle-income country.

Methods

The data from participants aged ≥60 years in the Fourth Thai National Health Examination Survey were used to construct the 30-item TFI. Cutoff points were created based on stratum-specific likelihood ratio. TFI ≤ 0.10 was categorized as fit, 0.10-0.25 as pre-frail, 0.25-0.45 as mildly frail, and >0.45 as severely frail. The association of frailty status with mortality was examined using Cox proportional hazard models.

Findings

Among 8,195 older adults with a mean age of 69.2 years, 1,284 died during the 7-year follow-up. The prevalence of frailty was 16.6%. The adjusted hazard ratio (aHR) for mortality in pre-frail was 1.76 (95% CI = 1.50-2.07), mildly frail 2.79 (95% CI = 2.33-3.35), and severely frail 6.34 (95% CI = 4.60-8.73). Having a caretaker in the same household alleviated mortality risk for severely frail participants with an aHR of 2.93 (95% CI = 1.92-4.46) compared with an aHR of 6.89 (95% CI = 3.87-12.26) among those living without a caretaker.

Interpretation

The severity of frailty classified by the modified TFI can predict long-term mortality risk for community-dwelling older adults. Identification of severely frail older people to provide appropriate care might alleviate mortality risk. Our findings can inform policymakers to appropriately allocate services in a resource-limited setting.

Concurrent and lagged associations of social participation and frailty among older adults

Frailty is a pervasive symptom among the older population, and social participation is a beneficial factor of late-life well-being. However, studies on the bidirectional association between social participation and frailty are limited. This study examined the cross-sectional and lagged associations of social participation and frailty. The analytic sample contained 6865 community-dwelling older adults, with 21,141 observations, from the first four waves (2011-2018) China Health and Retirement Longitudinal Study (CHARLS). Frailty was measured by the Frailty Index (FI). Social participation was measured by the accumulation of the frequencies of six social activities. Random intercept two-level models were used to analyse the concurrent and lagged association between social participation and frailty. The results showed significantly cross-sectional associations between higher levels of frailty and lower levels of social participation in the same wave. Moreover, there was a lagged association of social participation in the prior wave with the current frailty (b = -0.001, SE = 0.001, p = 0.028), and frailty in the prior wave with the current social participation (b = -0.634, SE = 0.088, p < 0.001) even after adjusting for sociodemographic characteristics, and frailty or social participation in the prior wave. The bidirectional associations between social participation and frailty imply the necessity of enhancing social participation to prevent or slow the frailty progression, and improving the physical and social environment to reduce social participation restrictions imposed by frailty status.

Sex-specific interventions to prevent and manage frailty

There is growing interest in interventions that delay, slow, and even reverse frailty. In this narrative review, we explore the evidence on exercise, nutrition, medication optimisation and social support interventions for frailty and consider how these relate to underlying frailty pathophysiology. We also consider pathophysiological mechanisms underpinning sex differences in frailty before evaluating the limited evidence for sex-specific frailty interventions that is currently available. Through this review of the literature, we generate a list of potential sex-specific interventions for frailty. While individual-level recommendations are certainly important, future work should turn the focus towards population-level interventions that take into account sex differences in frailty, including changes to healthcare and socioeconomic systems, as well as changes to the built environment to promote healthy behaviours.

Longitudinal Relationship Between Frailty and Cognitive Impairment in Chinese Older Adults: A Prospective Study

We aimed to examine the longitudinal association between frailty and cognitive impairment in the older Chinese population. This prospective cohort study used data from the Chinese Longitudinal Healthy Longevity Study 2011 wave. We calculated the follow-up duration as 3 years from the baseline year. Frailty was measured using the frailty index, and cognitive function was calculated by Mini-Mental State Examination Scale. Participants who were non-frailty and those with normal cognitive function were included in 2011 and followed up in 2014, respectively. Frailty was an independent risk factor for early-onset cognitive impairment. Age, hearing impairment, and a decreased ability to perform daily activities were the main risk factors for cognitive impairment, while affluent economic status was a protective factor. Cognitive impairment was not found to be an independent risk factor for frailty. We concluded that the frailty index is a significant predictor of cognitive impairment among community-dwelling older adults.

Frailty Risk Prediction Model among Older Adults: A Chinese Nation-Wide Cross-Sectional Study

OBJECTIVES

Numerous studies have been performed on frailty, but rarely do studies explore the integrated impact of socio-demographic, behavioural and social support factors on frailty. This study aims to establish a comprehensive frailty risk prediction model including multiple risk factors.

METHODS

The 2018 wave of the Chinese Longevity and Health Longitudinal Survey was used. Univariate and multivariate logistic regressions were performed to identify the relationship between frailty and multiple risk factors and establish the frailty risk prediction model. A nomogram was utilized to illustrate the prediction model. The area under the receiver operating characteristic curve (AUC), Hosmer-Lemeshow test and calibration curve were used to appraise the prediction model.

RESULTS

Variables from socio-demographic, social support and behavioural dimensions were included in the final frailty risk prediction model. Risk factors include older age, working as professionals and technicians before 60 years old, poor economic condition and poor oral hygiene. Protective factors include eating rice as a staple food, regular exercise, having a spouse as the first person to share thoughts with, doing physical examination once a year and not needing a caregiver when ill. The AUC (0.881), Hosmer-Lemeshow test (p = 0.618), and calibration curve showed that the risk prediction model was valid.

CONCLUSION

Risk factors from socio-demographic, behavioural and social support dimensions had a comprehensive effect on frailty, further supporting that a comprehensive and individualized intervention is necessary to prevent frailty.

Human age reversal: Fact or fiction?

Although chronological age correlates with various age‐related diseases and conditions, it does not adequately reflect an individual's functional capacity, well‐being, or mortality risk. In contrast, biological age provides information about overall health and indicates how rapidly or slowly a person is aging. Estimates of biological age are thought to be provided by aging clocks, which are computational models (e.g., elastic net) that use a set of inputs (e.g., DNA methylation sites) to make a prediction. In the past decade, aging clock studies have shown that several age‐related diseases, social variables, and mental health conditions associate with an increase in predicted biological age relative to chronological age. This phenomenon of age acceleration is linked to a higher risk of premature mortality. More recent research has demonstrated that predicted biological age is sensitive to specific interventions. Human trials have reported that caloric restriction, a plant‐based diet, lifestyle changes involving exercise, a drug regime including metformin, and vitamin D3 supplementation are all capable of slowing down or reversing an aging clock. Non‐interventional studies have connected high‐quality sleep, physical activity, a healthy diet, and other factors to age deceleration. Specific molecules have been associated with the reduction or reversal of predicted biological age, such as the antihypertensive drug doxazosin or the metabolite alpha‐ketoglutarate. Although rigorous clinical trials are needed to validate these initial findings, existing data suggest that aging clocks are malleable in humans. Additional research is warranted to better understand these computational models and the clinical significance of lowering or reversing their outputs.

Associations Between High-Sensitivity C-Reactive Protein and All-Cause Mortality Among Oldest-Old in Chinese Longevity Areas: A Community-Based Cohort Study

Background

The association between high-sensitivity C-reactive protein (hsCRP) levels and all-cause mortality for the oldest-old (aged 80 years or older) remains unclear. We aimed to investigate the associations between hsCRP concentrations and the risks of all-cause mortality, and further identify the potential modifying factors affecting these associations among the oldest-old.

Methods

This prospective, community-based cohort study included 2,206 participants aged 80 years or older (median age 93.0 years) from the Healthy Aging and Biomarkers Cohort Study. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) with 95% confidential intervals (95% CIs) for all-cause mortality according to hsCRP quartiles and recommendation for relative risk categories of hsCRP levels (< 1.0, 1.0–3.0, and > 3.0 mg/L), with adjustment for sociodemographic information, lifestyle, physical examination, medical history, and other potential confounders.

Results

During a median follow-up period of 3.1 years (IQR: 1.6–3.9 years), 1,106 deaths were verified. After full adjustment for potential confounders, a higher hsCRP concentration was positively associated with an increased risk of all-cause mortality (P for trend < 0.001). Compared with the lowest quartile, the fully adjusted HRs of the second, third, and fourth quartiles were 1.17 (95% CI: 0.94, 1.46), 1.28 (95% CI: 1.01, 1.61), and 1.49 (95% CI: 1.20, 1.87), respectively. The association of hsCRP with all-cause mortality was modified by smoking status (P for interaction = 0.011), an increased risk of hsCRP with all-cause mortality showed among non-current smokers (HR: 1.17; 95% CI: 1.07, 1.28), but no significance was observed in current smokers (HR: 0.83; 95% CI: 0.66, 1.18).

Conclusions

Our study indicated that elevated hsCRP concentrations were associated with a higher risk of all-cause mortality among Chinese oldest-old. Future studies investigating additional factors of disease and aging processes are needed to obtain a better understanding of the mechanisms.

A multi-centre cohort study on healthcare use due to medication-related harm: the role of frailty and polypharmacy

Objectives

To determine the association between frailty and medication-related harm requiring healthcare utilisation.

Design

Prospective observational cohort study.

Setting

Six primary and five secondary care sites across South East England, September 2013–November 2015.

Participants

One thousand and two hundred and eighty participants, ≥65 years old, who were due for discharge from general medicine and older persons’ wards following an acute episode of care. Exclusion criteria were limited life expectancy, transfer to another hospital and consent not gained.

Main outcome measures

Medication-related harm requiring healthcare utilisation (including primary, secondary or tertiary care consultations related to MRH), including adverse drug reactions, non-adherence and medication error determined via the review of data from three sources: patient/carer reports gathered through a structured telephone interview; primary care medical record review; and prospective consultant-led review of readmission to recruiting hospital. Frailty was measured using a Frailty Index, developed using a standardised approach. Marginal estimates were obtained from logistic regression models to examine how probabilities of healthcare service use due to medication-related harm were associated with increasing number of medicines and frailty.

Results

Healthcare utilisation due to medication-related harm was significantly associated with frailty (OR = 10.06, 95% CI 2.06–49.26, P = 0.004), independent of age, gender, and number of medicines. With increasing frailty, the need for healthcare use as a result of MRH increases from a probability of around 0.2–0.4. This is also the case for the number of medicines.

Conclusions

Frailty is associated with MRH, independent of polypharmacy. Reducing the burden of frailty through an integrated health and social care approach, alongside strategies to reduce inappropriate polypharmacy, may reduce MRH related healthcare utilisation.

Quantifying self-rated age

Chronological age, in conjunction with population life tables, is widely used for estimating future life expectancy. The aims of this study are to estimate a subjective ageing indicator, namely self-rated age, and to evaluate its concurrent validity in comparison with other age indicators: subjective survival probabilities, subjective age, and biological age. We use data from the Wave 6 of the Survey of Health, Ageing and Retirement in Europe, Wave 12 of the Health and Retirement Study in the United States, and life tables from the Human Mortality Database. For the statistical analysis we use multinomial regression models. Our results indicate that health status and frequency of physical activities imply similar patterns of self- rated age, subjective survival probabilities, subjective age, and biological age. However, the impact of cognitive function differs by geographical region. Self-rated age can be interpreted as a subjective adjustment that better reflects the ageing process.

Changes in late-life systolic blood pressure and all-cause mortality among oldest-old people in China: the chinese longitudinal healthy longevity survey

Background

Blood pressure targets for oldest-old people have been long debated due to the concern that more stringent targets are associated with increased mortality. We aimed to investigate the association between changes of late-life systolic blood pressure (SBP), mean SBP and SBP variability (SBPV), and all-cause mortality in oldest-old.

Methods

Based on the community-based Chinese Longitudinal Healthy Longevity Survey with follow-up conducted in the 3-year interval, we assembled a retrospective cohort of 6639 participants ≥ 80 years with available blood pressure measurements at baseline and second wave. The primary exposures were mean SBP and SBPV (defined as the annual difference in SBP divided by mean SBP) measured between baseline and second wave. The primary outcome was all-cause mortality assessed from the second wave.

Results

During 21443.1 person-years of follow-up, 4622 death was recorded. U-shaped associations of mortality with mean SBP and SBPV were identified; the value of 137 mmHg and 4.0 %/year conferred the minimum mortality risk, respectively. The associations of a larger SBPV with an increased mortality risk were observed for both rises and large falls in SBP. The hazard ratio was 1.11 (comparing lowest versus middle quintile; 95 % CI: 1.01, 1.22) with large falls in SBPV and 1.08 (comparing highest versus middle quintile; 95 % CI: 0.98, 1.18) with large rises in SBPV.

Conclusions

U-shaped associations between late-life SBP and SBPV and all-cause mortality were found. Our study suggests that a stable SBP level in the middle range is related to lower mortality risk in the oldest-old.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02492-4.

Impact of frailty and its inter-relationship with lean tissue wasting and malnutrition on kidney transplant waitlist candidacy and delisting

BACKGROUND & AIMS

Frailty and body composition contribute to adverse pre-transplant outcomes including hospitalization and waitlist mortality, but the interaction between frailty and body composition remains uncertain.

METHODS

Frailty was diagnosed by Clinical Frailty Scale (CFS) and a standard Frailty Questionnaire (FQ). Nutrition was evaluated by serum albumin level, subjective global assessment (SGA) and comprehensive malnutrition-inflammation score (MIS). Body composition was assessed by bioimpedance spectroscopy. All patients were followed up for three years. Primary outcome measure was a composite of death and permanent removal from waitlist. Secondary outcomes were emergency room attendance and hospitalization.

RESULTS

432 prevalent peritoneal dialysis (PD) patients were recruited. 148 (34.3%) were listed on transplant waitlist. Frailty, age and comorbidity load predicted waitlisting. With time, 47 patients were delisted. Frailty by FQ (p = 0.028), serum albumin level (p = 0.005) and waist circumference (p = 0.010) predicted delisting after adjustment for confounders. Frailty significantly interacted with lean tissue wasting (FQ: p = 0.002, CFS: p = 0.048), and MIS (FQ: p = 0.004; CFS: p = 0.014) on delisting. Lean tissue wasting caused 2.56 times risk of delisting among frail individuals identified by FQ (p = 0.016), while serum albumin and the presence of diabetes mellitus predicted the risk of delisting among non-frail individuals. Lean tissue wasted and frail subjects had a higher all-cause and infection-related hospitalization.

CONCLUSION

Frailty predicted both kidney transplant waitlisting and subsequent delisting. Frailty interacted with body composition on transplant waitlist delisting. Lean tissue wasting and malnutrition independently predicted delisting in frail and non-frail listed subjects respectively.

Vulnerable Older Adults' Identification, Geographic Distribution, and Policy Implications in China

With the population aging and urbanization in China, vulnerable older adults tend to show more complex characteristics, bringing great challenges to public health policies. Using China Longitudinal Aging Social Survey data 2014, this paper builds a comprehensive index system for the identification of vulnerable older adults from three dimensions, including health, economy, and social support, then divides older adults into four support levels and six small classes by using the typological method. The results show that older adults in urgent need of assistance or priority are those poor in health and economic conditions, 1.46% of them are highly vulnerable because of the lack of social support; 12.76% of them obtain a certain social support are moderately vulnerable; and 34.72% of them are slightly vulnerable with disadvantage in only one dimension. The geographic distribution of different types of vulnerable older adults varies significantly. The paper provides evidence to design more feasible and specific policies with comprehensive considerations for different types of vulnerable older adults residing in different regions.

The Importance of Age in the Prediction of Mortality by a Frailty Index: A Machine Learning Approach in the Irish Longitudinal Study on Ageing

The quantification of biological age in humans is an important scientific endeavor in the face of ageing populations. The frailty index (FI) methodology is based on the accumulation of health deficits and captures variations in health status within individuals of the same age. The aims of this study were to assess whether the addition of age to an FI improves its mortality prediction and whether the associations of the individual FI items differ in strength. We utilized data from The Irish Longitudinal Study on Ageing to conduct, by sex, machine learning analyses of the ability of a 32-item FI to predict 8-year mortality in 8174 wave 1 participants aged 50 or more years. By wave 5, 559 men and 492 women had died. In the absence of age, the FI was an acceptable predictor of mortality with AUCs of 0.7. When age was included, AUCs improved to 0.8 in men and 0.9 in women. After age, deficits related to physical function and self-rated health tended to have higher importance scores. Not all FI variables seemed equally relevant to predict mortality, and age was by far the most relevant feature. Chronological age should remain an important consideration when interpreting the prognostic significance of an FI.

Serum 25-hydroxyvitamin D, frailty, and mortality among the Chinese oldest old: Results from the CLHLS study

BACKGROUND AND AIMS

In this study, the aim is to explore whether frailty status modified the associations of serum 25(OH)D levels with all-cause and cause-specific mortality in the oldest old Chinese population.

METHODS AND RESULTS

A total of 1411 participants aged at least 80 years were enrolled in the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Information on serum 25(OH)D level, frailty status, and covariates were examined at baseline. All-cause and cause-specific mortality status were ascertained during the follow-up survey conducted in 2017-2018 by using the ICD-10 codes. Cox proportional hazard models with stratified analyses were performed to evaluate potential associations. Over a median follow-up of 3.2 years, 722 (51.2%) participants were deceased, including 202 deaths due to circulatory diseases, and 520 deaths due to noncirculatory causes. After multivariable adjustment, the lowest quartile of serum 25(OH)D levels (Hazard Ratios (95% Confidence Intervals), 1.85 (1.45-2.36), 1.85 (1.45-2.36), 1.73 (1.31-2.29), respectively) and frailty (Odd Ratios (95% Confidence Intervals), 1.91 (1.60-2.29), 2.67 (1.90-3.74), 1.64 (1.31-2.05)) were associated with significantly higher risk of all-cause mortality, circulatory mortality, and noncirculatory mortality, respectively. In addition, we observed significant interactions among 25(OH)D and frailty on the risk of all-cause and cause-specific mortality (all P-interaction < 0.001). Similar results were found in sensitivity analyses by excluding participants who died in the first year of follow-up and using clinical cutoffs of serum 25(OH)D levels.

CONCLUSION

Low serum 25(OH)D levels were associated with higher risk of all-cause and cause-specific mortality among the oldest old of the Chinese population, and the associations were significantly stronger in individuals with frailty.

Biological age in healthy elderly predicts aging-related diseases including dementia

Application of biological age as a measure of an individual´s health status offers new perspectives into extension of both lifespan and healthspan. While algorithms predicting mortality and most aging-related morbidities have been reported, the major shortcoming has been an inability to predict dementia. We present a community-based cohort study of 1930 participants with a mean age of 72 years and a follow-up period of over 7 years, using two variants of a phenotypic blood-based algorithm that either excludes (BioAge1) or includes (BioAge2) neurofilament light chain (NfL) as a neurodegenerative marker. BioAge1 and BioAge2 predict dementia equally well, as well as lifespan and healthspan. Each one-year increase in BioAge1/2 was associated with 11% elevated risk (HR 1.11; 95%CI 1.08-1.14) of mortality and 7% elevated risk (HR 1.07; 95%CI 1.05-1.09) of first morbidities. We additionally tested the association of microRNAs with age and identified 263 microRNAs significantly associated with biological and chronological age alike. Top differentially expressed microRNAs based on biological age had a higher significance level than those based on chronological age, suggesting that biological age captures aspects of aging signals at the epigenetic level. We conclude that accelerated biological age for a given age is a predictor of major age-related morbidity, including dementia, among healthy elderly.

Sex differences in frailty: Comparisons between humans and preclinical models

Frailty can be viewed as a state of physiological decline that increases susceptibility to adverse health outcomes. This loss of physiological reserve means that even small stressors can lead to disability and death in frail individuals. Frailty can be measured with various clinical tools; the two most popular are the frailty index and the frailty phenotype. Clinical studies have used these tools to show that women are frailer than men even though they have longer lifespans. Still, factors responsible for this frailty-mortality paradox are not well understood. This review highlights evidence for male-female differences in frailty from both the clinical literature and in animal models of frailty. We review evidence for higher frailty levels in female animals as seen in many preclinical models. Mechanisms that may contribute to sex differences in frailty are highlighted. In addition, we review work that suggests frailty may play a role in susceptibility to chronic diseases of aging in a sex-specific fashion. Additional mechanistic studies in preclinical models are needed to understand factors involved in male-female differences in frailty in late life.

Trajectories of frailty in aging: Prospective cohort study

Background

Emerging evidence suggests that there is significant variability in the progression of frailty in aging. We aimed to identify latent subpopulations of frailty trajectories, and examine their clinical and biological correlates.

Methods

We characterized frailty using a 41-item cumulative deficit score at baseline and annual visits up to 12 years in 681 older adults (55% women, mean age 74·6 years). Clinical risk profile and walking while talking performance as a clinical marker of trajectories were examined. Mortality risk associated with trajectories was evaluated using Cox regression adjusted for established survival predictors, and reported as hazard ratios (HR). Proteome-wide analysis was done.

Findings

Latent class modeling identified 4 distinct frailty trajectories: relatively stable (34·4%) as well as mild (36·1%), moderate (24·1%) and severely frail (5·4%). Four distinct classes of frailty trajectories were also shown in an independent sample of 515 older adults (60% women, 68% White, 26% Black). The stable group took a median of 31 months to accumulate one additional deficit compared to 20 months in the severely frail group. The worst trajectories were associated with modifiable risk factors such as low education, living alone, obesity, and physical inactivity as well as slower walking while talking speed. In the pooled sample, mild (HR 2·33, 95% CI 1·30–4·18), moderate (HR 2·49, 95% CI 1·33–4·66), and severely frail trajectories (HR 5·28, 95% CI 2·68–10·41) had higher mortality compared to the stable group. Proteomic analysis showed 11 proteins in lipid metabolism and growth factor pathways associated with frailty trajectories.

Conclusion

Frailty shows both stable and accelerated patterns in aging, which can be distinguished clinically and biologically.

How Old Is My Dog? Identification of Rational Age Groupings in Pet Dogs Based Upon Normative Age-Linked Processes

Behavioral development is a lifelong process where cognitive traits such as learning and memory may be expected to take quadratic or linear trajectories. It is common practice for operational purposes to reduce study subjects into chronological categories when conducting research. However, there are no agreed-upon thresholds for this practice, and the lack of standardization may hinder comparison between studies of normative and pathological aging. In this perspective review, chronological categories have been identified that can be considered to represent normative cognitive and neurological aging in domestic family dogs. These categories work to capture age-related developmental trajectories for the majority of dog breeds. It is encouraged that researchers studying cognition and behavior, pathological cognitive deficits, or welfare of dogs across age categories utilize the categories presented here to best enable comparison between studies. The proposed groups could also support education programs informing owners of what behavioral changes to expect in their dog as they age, but they cannot be used to reflect health-based needs associated with breed-specific morbidity. The use of the age categories proposed here highlights significant welfare issues for breeds with the shortest average lifespans (e.g., the Great Dane). Studies show no evidence of an increased rate of behavioral or cognitive aging in short-lived breeds, and the shortest-lived breeds are most likely to die when classified by the proposed categories as Mature Adults. Adoption of these chronological categories in future research would aid comparison between studies and identification of non-normative age-related pathologies.

Validation of the Korean Frailty Index in community-dwelling older adults in a nationwide Korean Frailty and Aging Cohort study

BACKGROUND/AIMS

We aimed to assess validity of the Korean Frailty Index (KFI) and the modified KFI (mKFI) in nationwide Korean population as screening measures for frailty status in older adults.

METHODS

Analysis was performed in the records of baseline assessments of 2,886 participants in the Korean Frailty Aging Cohort study from 2016 to 2017. The KFI included eight items on a history of hospitalization, self-reported health status, polypharmacy, weight loss, mood, incontinence, sensory problems, and timed up and go test. In mKFI, timed up and go test was replaced with a question whether a person can walk around a schoolyard. Cardiovascular Health Study (CHS) frailty scale was used as a gold standard.

RESULTS

In study population (mean age, 76; 47.6% men), score of the KFI correlated with the CHS scale. The KFI correlated with common geriatric parameters including Activities of Daily Living, nutritional status, cognitive performance, and mood. As a construct validity, items of KFI correlated with CHS scale. As a criterion validity, sensitivity was 81.6%, specificity was 67.0% to predict frailty by CHS scale with the score of 3 or higher in KFI. The KFI and mKFI correlated with each other (R2 = 0.88), and prediction ability for frailty by CHS scale was not significantly differed between KFI and mKFI.

CONCLUSION

The KFI and mKFI are valid instruments for frailty screening and might be useful as simple frailty screening tools to identify older adults who might benefit from comprehensive geriatric assessment and integrated, multidisciplinary geriatric care services.

Dynamic statistical model for predicting the risk of death among older Chinese people, using longitudinal repeated measures of the frailty index: a prospective cohort study

BACKGROUND

Frailty is a common characteristic of older people with the ageing process. We aimed to develop and validate a dynamic statistical prediction model to calculate the risk of death in people aged ≥65 years, using a longitudinal frailty index (FI).

METHODS

One training dataset and three validation datasets from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) were used in our study. The training dataset and validation datasets 1 to 3 included data from 9,748, 7,459, 9,093 and 6,368 individuals, respectively. We used 35 health deficits to construct the FI and a longitudinal FI based on repeated measurement of FI at every wave of the CLHLS. A joint model was used to build a dynamic prediction model considering both baseline covariates and the longitudinal FI. Areas under time-dependent receiver operating characteristic curves (AUCs) and calibration curves were employed to assess the predictive performance of the model.

RESULTS

A linear mixed-effects model used time, sex, residence (city, town, or rural), living alone, smoking and alcohol consumption to calculate a subject-specific longitudinal FI. The dynamic prediction model was built using the longitudinal FI, age, residence, sex and an FI-age interaction term. The AUCs ranged from 0.64 to 0.84, and both the AUCs and the calibration curves showed good predictive ability.

CONCLUSIONS

We developed a dynamic prediction model that was able to update predictions of the risk of death as updated measurements of FI became available. This model could be used to estimate the risk of death in individuals aged >65 years.

Impact of frailty on surgery for glioblastoma: a critical evaluation of patient outcomes and caregivers' perceptions in a developing country

OBJECTIVE

The authors aimed to evaluate the impact of age and frailty on the surgical outcomes of patients with glioblastoma (GBM) and to assess caregivers' perceptions regarding postdischarge care and challenges faced in the developing country of India.

METHODS

This was a retrospective study of patients with histopathologically proven GBM from 2009 to 2018. Data regarding the clinical and radiological characteristics as well as surgical outcomes were collected from the institute's electronic database. Taking Indian demographics into account, the authors used the cutoff age of 60 years to define patients as elderly. Frailty was estimated using the 11-point modified frailty index (mFI-11). Patients were divided into three groups: robust, with an mFI score of 0; moderately frail, with an mFI score of 1 or 2; and severely frail, with an mFI score ≥ 3. A questionnaire-based survey was done to assess caregivers' perceptions about postdischarge care.

RESULTS

Of the 276 patients, there were 93 (33.7%) elderly patients and 183 (66.3%) young or middle-aged patients. The proportion of severely frail patients was significantly more in the elderly group (38.7%) than in the young or middle-aged group (28.4%) (p < 0.001). The authors performed univariate and multivariate analysis of associations of different short-term outcomes with age, sex, frailty, and Charlson Comorbidity Index. On the multivariate analysis, only frailty was found to be a significant predictor for in-hospital mortality, postoperative complications, and length of hospital and ICU stay (p < 0.001). On Cox regression analysis, the severely frail group was found to have a significantly lower overall survival rate compared with the moderately frail (p = 0.001) and robust groups (p < 0.001). With the increase in frailty, there was a concomitant increase in the requirement for readmissions (p = 0.003), postdischarge specialist care (p = 0.001), and help from extrafamilial sources (p < 0.001). Greater dissatisfaction with psychosocial and financial support among the caregivers of severely frail patients was seen as they found themselves ill-equipped to provide postdischarge care at home (p < 0.001).

CONCLUSIONS

Frailty is a better predictor of poorer surgical outcomes than chronological age in terms of duration of hospital and ICU stay, postoperative complications, and in-hospital mortality. It also adds to the psychosocial and financial burdens of the caregivers, making postdischarge care challenging.

Complications, Additional Surgery, and Joint Survival Analysis After Medial Open-Wedge High Tibial Osteotomy

The reported incidence of complications following medial open-wedge high tibial osteotomy (MOWHTO) varies. The authors sought to assess the complications, additional surgeries, and joint survival following MOWHTO in patients with isolated medial compartment arthrosis during a mean follow-up of 10 years. This retrospective study involved patients implanted with spacer plates, angle adjustable plates, or inverse L-type plates with wedges between 2000 and 2010. A total of 504 knees from 441 patients were examined. Mean age of the study population was 52.6±7.0 years, with 56 (11.1%) knees from men and 448 (88.9%) from women. The 10-year Kaplan-Meier joint survival rate was 94.8%. Overall complication rate for MOWHTO was 63.7%, with complications in 20.3% of treated knees requiring additional surgery. In this population, although the overall complication rate and the need for additional surgery were high, the need for additional surgery resulting from serious complications was low (2.6%). The high joint survival rate and low rate of additional surgery for serious complications indicate that MOWHTO can be safely applied in patients with isolated medial gonarthrosis. [Orthopedics. 2020;43(5):303-314.].

Loneliness as a risk factor for frailty transition among older Chinese people

Background

Previous literature has reported that loneliness is a strong predictor of frailty risk. However, less is known about the role of loneliness in frailty transition types. This study aimed to examine whether and how loneliness are related to frailty transition among older Chinese people.

Methods

Our study used participants (aged ≥60 years) from 2008/2009, 2011/2012 and 2014 waves of the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Loneliness was assessed by a single question asking how often the respondent feels lonely. The FRAIL Scale was created to measure physical frailty for our study, and frailty was also assessed by a broader definition of the frailty index. Frailty transition as an outcome variable has been designed as two types according to the measurement of frailty.

Results

Greater loneliness at baseline reduced the possibility of remaining in a robust or prefrail physical frailty state after 3 years (OR = 0.78, 95%CI: 0.68–0.91, p < 0.01). Greater loneliness was associated with an increased risk of worsening physical frailty over time: compared with those who had never felt lonely, the odds ratios for people who often felt lonely were 1.19 (95%CI: 1.01–1.41, p < 0.05) after 3 years and 1.34 (95%CI: 1.08–1.66, p < 0.01) after 6 years. The association between loneliness and change in the frailty index differed in the survey periods: loneliness at baseline was found to increase the possibility of participants remaining in frailty (seldom loneliness: OR = 1.78, 95%CI: 1.25–2.55, p < 0.01; often loneliness: OR = 1.74, 95%CI: 1.21–2.50, p < 0.01) after 6 years, but no significance was shown in the 3-year follow up. Additionally, loneliness at baselines was significantly associated with frailty transition at follow up among the male participants. However, a similar association was not observed among the female participants.

Conclusion

Older people with a high level of loneliness tend to be frail in the future, and greater loneliness is related to an increased risk of worsening frailty and remaining frail. Male elderly with a high level of loneliness were more likely to have a worse frailty transition than female elderly in China.

Assessing Global Frailty Scores: Development of a Global Burden of Disease-Frailty Index (GBD-FI)

Frailty is an independent age-associated predictor of morbidity and mortality. Despite this, many countries lack population estimates with large heterogeneity between studies. No population-based standardised metric for frailty is available. We applied the deficit accumulation model of frailty to create a frailty index (FI) using population-level estimates from the Global Burden of Disease (GBD) 2017 study across 195 countries to create a novel GBD frailty index (GBD-FI). Standard FI criteria were applied to all GBD categories to select GBD-FI items. Content validity was assessed by comparing the GBD-FI with a selection of established FIs. Properties including the rate of deficit accumulation with age were examined to assess construct validity. Linear regression models were created to assess if mean GBD-FI scores predicted one-year incident mortality. From all 554 GBD items, 36 were selected for the GBD-FI. Face validity against established FIs was variable. Characteristic properties of a FI—higher mean score for females and a deficit accumulation rate of approximately 0.03 per year, were observed. GBD-FI items were responsible for 19% of total Disability-Adjusted Life Years for those aged ≥70 years in 2017. Country-specific mean GBD-FI scores ranged from 0.14 (China) to 0.19 (Hungary) and were a better predictor of mortality from non-communicable diseases than age, gender, Healthcare Access and Quality Index or Socio-Demographic Index scores. The GBD-FI is a valid measure of frailty at population-level but further external validation is required.

Frailty: A cost incurred by reproduction?

Evolutionary theories of senescence, such as the ‘disposable soma’ theory, propose that natural selection trades late survival for early fecundity. ‘Frailty’, a multidimensional measure of health status, may help to better define the long-term consequences of reproduction. We examined the relationship between parity and later life frailty (as measured by the Frailty Index) in a sample of 3,534 adults aged 65 years and older who participated in the English Longitudinal Study of Ageing. We found that the most parous adults were the most frail and that the parity-frailty relationship was similar for both sexes. Whilst this study provided some evidence for a ‘parity-frailty trade-off’, there was little support for our hypothesis that the physiological costs of childbearing influence later life frailty. Rather, behavioural and social factors associated with rearing many children may have contributed to the development of frailty in both sexes.

Composite Measure of Physiological Dysregulation as a Predictor of Mortality: The Long Life Family Study

Biological aging results in changes in an organism that accumulate over age in a complex fashion across different regulatory systems, and their cumulative effect manifests in increased physiological dysregulation (PD) and declining robustness and resilience that increase risks of health disorders and death. Several composite measures involving multiple biomarkers that capture complex effects of aging have been proposed. We applied one such approach, the Mahalanobis distance (D_M), to baseline measurements of various biomarkers (inflammation, hematological, diabetes-associated, lipids, endocrine, renal) in 3,279 participants from the Long Life Family Study (LLFS) with complete biomarker data. We used D_M to estimate the level of PD by summarizing information about multiple deviations of biomarkers from specified “norms” in the reference population (here, LLFS participants younger than 60 years at baseline). An increase in D_M was associated with significantly higher mortality risk (hazard ratio per standard deviation of D_M: 1.42; 95% confidence interval: [1.3, 1.54]), even after adjustment for a composite measure summarizing 85 health-related deficits (disabilities, diseases, less severe symptoms), age, and other covariates. Such composite measures significantly improved mortality predictions especially in the subsample of participants from families enriched for exceptional longevity (the areas under the receiver operating characteristic curves are 0.88 vs. 0.85, in models with and without the composite measures, p = 2.9 × 10⁻⁵). Sensitivity analyses confirmed that our conclusions are not sensitive to different aspects of computational procedures. Our findings provide the first evidence of association of PD with mortality and its predictive performance in a unique sample selected for exceptional familial longevity.

Determinants and indicators of successful ageing associated with mortality: a 4-year population-based study

Successful aging may be a solution to the major challenges that population aging poses to healthcare systems, financial security, and labor force supply. Hence, we studied the value of factors discovered by exploratory factor analysis in predicting four main indicators of successful aging, and their association with mortality. We followed-up a nationally representative sample of 1284 older adults for a median of 50 months. Successful aging was defined by fast walking, independence, emotional vitality, and self-rated health. Exploratory factor analysis revealed five determinants: physical activity, life satisfaction and financial status, health status, stress, and cognitive function. Physical activity and health status were significant factors in living independently. Life satisfaction and financial status were associated with walking speed. Stress was solely associated with emotional vitality. Life satisfaction and financial status, and health status, were important predictors of self-rated health. Compared to people without any successful aging indicators, those with one, two, three, or four showed dose-dependent lessening of mortality risk, with respective hazard ratios of 0.39 (95% CI 0.25-0.59), 0.29 (95% CI 0.17-0.50), 0.23 (95% CI 0.11-0.51), and 0.09 (95% CI 0.01-0.66). These associations were stronger in males, older adults, smokers, and drinkers, than in their counterparts.

Determinants of frailty development and progression using a multidimensional frailty index: Evidence from the English Longitudinal Study of Ageing

Objective

To identify modifiable risk factors for development and progression of frailty in older adults living in England, as conceptualised by a multidimensional frailty index (FI).

Methods

Data from participants aged 50 and over from the English Longitudinal Study of Ageing (ELSA) was used to examine potential determinants of frailty, using a 56-item FI comprised of self-reported health conditions, disabilities, cognitive function, hearing, eyesight, depressive symptoms and ability to carry out activities of daily living. Cox proportional hazards regression models were used to measure frailty development (n = 7420) and linear regression models to measure frailty progression over 12 years follow-up (n = 8780).

Results

Increasing age (HR: 1.08 (CI: 1.08–1.09)), being in the lowest wealth quintile (HR: 1.79 (CI: 1.54–2.08)), lack of educational qualifications (HR: 1.19 (CI: 1.09–1.30)), obesity (HR: 1.33 (CI: 1.18–1.50) and a high waist-hip ratio (HR: 1.25 (CI: 1.13–1.38)), being a current or previous smoker (HR: 1.29 (CI: 1.18–1.41)), pain (HR: 1.39 (CI: 1.34–1.45)), sedentary behaviour (HR: 2.17 (CI: 1.76–2.78) and lower body strength (HR: 1.07 (CI: 1.06–1.08)), were all significant risk factors for frailty progression and incidence after simultaneous adjustment for all examined factors.

Conclusion

The findings of this study suggest that there may be scope to reduce both frailty incidence and progression by trialling interventions aimed at reducing obesity and sedentary behaviour, increasing intensity of physical activity, and improving success of smoking cessation tools. Furthermore, improving educational outcomes and reducing poverty may also reduce inequalities in frailty.

The accumulation of deficits approach to describe frailty

The advancing age of the participants of the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam study was the incentive to investigate frailty as a major parameter of ageing. The aim of this study was to develop a multidimensional tool to measure frailty in an ageing, free-living study population. The "accumulation of deficits approach" was used to develop a frailty index (FI) to characterize a sub-sample (N = 815) of the EPIC-Potsdam (EPIC-P) study population regarding the aging phenomenon. The EPIC-P frailty index (EPIC-P-FI) included 32 variables from the following domains: health, physical ability, psychosocial and physiological aspects. P-values were calculated for the linear trend between sociodemographic and life style variables and the EPIC-P-FI was calculated using regression analysis adjusted for age. The relationship between the EPIC-P-FI and age was investigated using fractional polynomials. Some characteristics such as age, education, time spent watching TV, cycling and a biomarker of inflammation (C-reactive protein) were associated with frailty in men and women. Interestingly, living alone, having no partner and smoking status were only associated with frailty in men, and alcohol use and physical fitness (VO2max) only in women. The generated, multidimensional FI, adapted to the EPIC-P study, showed that this cohort is a valuable source for further exploration of factors that promote healthy ageing.

Frailty Quantified by the "Valencia Score" as a Potential Predictor of Lifespan in Mice

The development of frailty scores suitable for mice and which resemble those used in the clinical scenario is of great importance to understand human frailty. The aim of the study was to determine an individual frailty score for each mouse at different ages and analyze the association between the frailty score and its lifespan. For this purpose, the "Valencia Score" for frailty was used. Thus, a longitudinal study in mice was performed analyzing weight loss, running time and speed, grip strength and motor coordination at the late-adult, mature and old ages (40, 56 and 80 weeks old, respectively). These parameters are equivalent to unintentional weight loss, poor endurance, slowness, weakness, and low activity level, respectively, in humans. A cut-off point was used to identify frail mice for each criterion. All the measurements were also performed on chronologically adult prematurely aging mice. The results show that by using the "Valencia Score" for frailty a prematurely aged phenotype can be identified even during the adulthood of animals. This opens up the possibility of carrying out preventive long-term interventions. Moreover, the individual frailty score of a given mouse at the late-adult, mature and old ages is shown to be a relevant predictor of its lifespan.

Further defence of legal age change: a reply to the critics

In 'Moral case for legal age change', I argue that sometimes people should be allowed to change their age. I refute six immediate objections against the view that age change is permissible. I argue that the objections cannot show that legal age change should always be prohibited. In this paper, I consider some further objections against legal age change raised by Iain Brassington, Toni Saad and William Simkulet. I argue that the objections fail to show that age change should never be allowed.

Plasma 25-Hydroxyvitamin D Concentrations Are Inversely Associated with All-Cause Mortality among a Prospective Cohort of Chinese Adults Aged ≥80 Years

BACKGROUND

High concentrations of plasma 25-hydroxyvitamin D [25(OH)D], a marker of circulating vitamin D, have been associated with a lower risk of mortality in epidemiologic studies of multiple populations, but the association for Chinese adults aged ≥80 y (oldest old) remains unclear.

OBJECTIVE

We investigated the association between plasma [25(OH)D] concentration and all-cause mortality among Chinese adults aged ≥80 y.

DESIGN

The present study is a prospective cohort study of 2185 Chinese older adults (median age: 93 y). Prospective all-cause mortality data were analyzed for survival in relation to plasma 25(OH)D using Cox proportional hazards regression models, with adjustments for potential sociodemographic and lifestyle confounders and biomarkers. The associations were measured with HR and 95% CIs.

RESULTS

The median plasma 25(OH)D concentration was 34.4 nmol/L at baseline. Over the 5466 person-year follow-up period, 1100 deaths were identified. Men and women were analyzed together as no effect modification by sex was found. After adjusting for multiple potential confounders, the risk of all-cause mortality decreased as the plasma 25(OH)D concentration increased (P-trend <0.01). Compared with the lowest age-specific quartile of plasma 25(OH)D, the adjusted HRs for mortality for the second, third, and fourth age-specific quartiles were 0.72 (95% CI: 0.57, 0.90), 0.73 (95% CI: 0.58, 0.93), and 0.61 (95% CI: 0.47, 0.81), respectively. The observed associations were broadly consistent across age and other subgroups. Sensitivity analyses generated similar results after excluding participants who died within 2 y of follow-up or after further adjustment for ethnicity and chronic diseases.

CONCLUSIONS

A higher plasma 25-hydroxyvitamin D concentration was associated with a reduced risk of all-cause mortality among Chinese adults aged ≥80 y. This observed inverse association warrants further investigation in randomized controlled trials testing vitamin D supplementation in this age group.

Associations between a laboratory frailty index and adverse health outcomes across age and sex

OBJECTIVE

Early frailty may be captured by a frailty index (FI) based entirely on vital signs and laboratory tests. Our aim was to examine associations between a laboratory-based FI (FI-Lab) and adverse health outcomes, and investigate how this changed with age.

METHODS

Up to 8988 individuals aged 20+ years from the 2003-2004 and 2005-2006 National Health and Nutrition Examination Survey cohorts were included. Characteristics of the FI-Lab were compared to those of a self-reported clinical FI. Associations between each FI and health care use, self-reported health, and disability were examined in the full sample and across age groups.

RESULTS

Laboratory-based FI scores increased with age but did not demonstrate expected sex differences. Women aged 20-39 years had higher FI scores than men; this pattern reversed after age 60 years. FI-Lab scores were associated with poor self-reported health (odds ratio[95% confidence interval]: 1.46[1.39-1.54]), high health care use (1.35[1.29-1.42]), and high disability (1.41[1.32-1.50]), even among those aged 20-39 years.

CONCLUSION

Higher FI-Lab scores were associated with poor health outcomes at all ages. Associations in the youngest group support the notion that deficit accumulation occurs across the lifespan. FI-Lab scores could be utilized as an early screening tool to identify deficit accumulation at the cellular and molecular level before they become clinically visible.