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

Cross-sectional and longitudinal associations between physical activity and intrinsic capacity in healthy older adults from the MAPT study

BACKGROUND

The construct of intrinsic capacity (IC) has been recently developed with the aim of assessing and monitoring life-long individuals' functional trajectories. Physical activity (PA) is recognized for its benefits on health but its associations with IC remain less investigated. We explored the cross-sectional and longitudinal associations of PA with IC in non-demented older adults.

METHODS

Eight hundred and thirty-seven males and females aged 70 years and over, were included in the present work. IC and its domains (mobility, vitality, cognition, psychology and sensory) were assessed over 2 years and converted to a 0-100 scale. Participants were categorized into 5 PA groups (0-29; 30-499; 500-999; 1000-1999; and 2000+ MET-min/week) using questionnaires. The associations between PA and IC variables (all reflected and square-root-transformed) observed over 2 years were examined using mixed-effect linear regressions.

FINDINGS

Over the 2-year follow-up, ordinal PA was associated with higher scores in IC (B = -0.066, SE = 0.015, p < .001) In addition, compared to the inactive group, most of the active groups had a slower decline in IC (B30-499 MET-min/week = -0.196, SE = 0.078; B500-999 MET-min/week = -0.208, SE = 0.076; B1000-1999 MET-min/week = -0.165, SE = 0.073; B2000+MET-min/week = -0.187, SE = 0.074; all p < .05). Subdomain analyses revealed that these associations were driven by mobility, vitality and psychological domain.

INTERPRETATION

This study suggests that PA may help preventing IC decline, especially mobility, vitality, and psychology in older adults.

Sleep disturbances and intrinsic capacity trajectories among Chinese older adults: The Rugao Longevity and Ageing Study

Age related decline of intrinsic capacity (IC) is the core of the functional ability and risk factor of adverse outcomes such as disability, hospitalization, and mortality. However, the relationship between sleep disturbance and IC decline are largely unknown. We conducted a longitudinal study and used data of 1514 community elders from the aging arm of the Rugao Longevity and Ageing Study. We found that poor sleep quality is cross-sectional associated with an increased risk of lower IC. In longitudinal analysis, sleep disturbances were inversely associated with composite IC score changes after adjusting for confounders (PSQI>5 vs. PSQI≤5: mean difference [-0.23], P = 0.0005), suggesting that poor sleep quality was associated with a decline in IC during the follow-up period. In conclusion, sleep disturbances were associated with worse IC changes. The results suggest that improving sleep health may help prevent IC decline and hence decreasing the burden of geriatric nursing practice.

Development and validation of an intrinsic capacity score in the UK Biobank study

BACKGROUND

In 2015, the World Health Organization introduced the concept of intrinsic capacity (IC) to define the individual-level characteristics that enable an older person to be and do the things they value. This study developed an intrinsic capacity score for UK Biobank study participants and validated its use as a tool for health outcome prediction, understanding healthy aging trajectories, and genetic research.

METHODS

Our analysis included data from 45,208 UK biobank participants who had a complete record of the ten variables included in the analysis. Factor adequacy was tested using Kaiser-Meyer-Olkin, Barthelt's, and the determinant of matrix tests, and the number of factors was determined by the parallel analysis method. Exploratory and confirmatory factor analyses were employed to determine the structure and dimensionality of indicators. Finally, the intrinsic capacity score was generated, and its construct and predictive validities as well as reliability were assessed.

RESULTS

The factor analysis identified a multidimensional construct comprising one general factor (intrinsic capacity) and five specific factors (locomotor, vitality, cognitive, psychological, and sensory). The bifactor structure showed a better fit (comparative fit index = 0.995, Tucker Lewis index = 0.976, root mean square error of approximation = 0.025, root mean square residual = 0.009) than the conventional five-factor structure. The intrinsic capacity score generated using the bifactor confirmatory factor analysis has good construct validity, as demonstrated by an inverse association with age (lower intrinsic capacity in older age; (β) =-0.035 (95%CI: -0.036, -0.034)), frailty (lower intrinsic capacity score in prefrail participants, β = -0.104 (95%CI: (-0.114, -0.094)) and frail participants, β = -0.227 (95%CI: -0.267, -0.186) than robust participants), and comorbidity (a lower intrinsic capacity score associated with increased Charlson's comorbidity index, β =-0.019 (95%CI: -0.022, -0.015)). The intrinsic capacity score also predicted comorbidity (a one-unit increase in baseline intrinsic capacity score led to a lower Charlson's comorbidity index, β = 0.147 (95%CI: -0.173, -0.121)) and mortality (a one-unit increase in baseline intrinsic capacity score led to 25 % lower risk of death, odds ratio = 0.75(95%CI: 0.663, 0.848)).

CONCLUSION

The bifactor structure showed a better fit in all goodness of fit tests. The intrinsic capacity construct has strong structural, construct, and predictive validities and is a promising tool for monitoring aging trajectories.

Enhancing Intrinsic Capacity and Related Biomarkers in Community-Dwelling Multimorbid Older Adults Through Integrated Multidomain Interventions: Ancillary Findings From the Taiwan Integrated Geriatric (TIGER) Trial

OBJECTIVE

This study aimed to evaluate the efficacy of integrated multidomain interventions and primary health care on intrinsic capacity (IC) and related biomarkers.

DESIGN

An ancillary analysis from the Taiwan Integrated Geriatric Care (TIGER) study: a randomized controlled trial.

SETTING AND PARTICIPANTS

A total of 398 community-dwelling older adults aged ≥65 years with ≥3 chronic conditions.

METHODS

Participants were randomized into the 12-month pragmatic multidomain intervention or usual care groups. The primary outcome was the change in IC and its subdomains (locomotion, cognition, vitality, psychological, and sensory) at baseline and 3-, 6-, 9-, and 12-month follow-ups. Generalized linear mixed models were used to evaluate the multidomain intervention effects on these changes.

RESULTS

The intervention arm had greater improvement in IC than the usual care arm (overall difference 1.5; 95% CI 0.5-2.5; P = .005), mainly from subdomains of locomotion (overall difference 1.4; 95% CI 0.5-2.4; P = .004) and cognition (2.9; 95% CI 2.1-3.7; P < .001). Changes in neutrophil-to-lymphocyte ratio (NLR -2.4; 95% CI -3.9 to -0.8, P = .003), serum levels of albumin (35.1; 95% CI 23.1-47.2; P < .001), dehydroepiandrosterone sulfate (DHEA-S 2.8; 95% CI 1.9-3.8; P < .001), free androgen index (FAI 1.5; 95% CI 1.1-1.9; P < .001), and vitamin D (4.0; 95% CI 2.0-6.1; P < .001) were associated with changes in IC over time.

CONCLUSIONS AND IMPLICATIONS

The incorporation of multidomain interventions into primary health care significantly enhanced IC over the 12-month program. Changes in NLR, FAI, and serum levels of albumin, DHEA-S, vitamin D were associated with changes in IC over time.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03528005.

Towards a core outcome set (COS) for intrinsic capacity (IC) intervention studies in adults in midlife and beyond: a scoping review to identify frequently used outcomes and measurement tools

This scoping review was conducted to identify the outcomes and measurement tools used in IC intervention studies, as first step towards the development of a core outcome set (COS) for IC trials. PRISMA-ScR and COS-STAD were followed. The review considered randomized controlled trials targeting IC published in Medline, Scopus, Embase, Cochrane Central Register of Controlled Trials, and clinicaltrials.gov, until June 2023. Of 699 references, 534 studies were screened once duplicates were removed, 15 were assessed for eligibility, and 7 (4 articles and 3 protocols) met eligibility criteria. Twenty-eight outcomes were identified (19 related to IC and its domains and 9 unrelated). The most reported primary outcome was the change in IC levels postintervention (5 over 7 studies) and the most reported outcomes (either as primary and/or secondary) were the changes in physical performance and in depressive symptoms (6 over 7 studies). Fifty-five tools used to construct the domains' z-scores and/or assess the effect of interventions were identified (47 related to IC and its domains and 8 unrelated). The most reported tool was an IC Z-score, calculated by 4 domains' z-scores: locomotor, vitality, cognitive, and psychological (5 over 7 studies). The tools differed among studies (10 locomotor related, 6 vitality related, 16 cognitive related, 8 psychological related, 6 sensorial related, 8 unrelated tools). The vast heterogeneity (28 outcomes and 55 tools within 7 studies) highlighted the need of a COS. These outcomes and tools will be presented to experts in a future step, to select the ones that should be taken into consideration in IC trials.

Evaluating the impact of aerobic and resistance green exercises on the fitness, aerobic and intrinsic capacity of older individuals

OBJECTIVE

Our study determined the impact of 12-week aerobic exercise (AE) and aerobic + resistance exercises (AE + RE) within the green exercise concept, on senior fitness, aerobic capacity, and intrinsic capacity (IC).

METHODS

The study was a multicenter, randomized controlled study conducted at two senior living facilities with individuals aged 65 and above whose cardiorespiratory and musculoskeletal conditions are suitable for moderate exercise and who have normal cognition levels. Block randomization was applied to 96 participants in a ratio of 1:1:1 to be assigned to AE, AE + RE, and control (C) groups. Intervention groups received exercise sessions led by physiotherapists within the senior living facilitiy gardens, with a frequency of once a week for 50 min, for 12 weeks. Also, they were prescribed additional exercise sessions on two additional days of the week. At the commencement of the study and 12th week, shuttle walking test, senior fitness test (SFT), intrinsic capacity assessment (with Timed Up and Go test, Mini Mental State Examination, Geriatric Depression Scale-15, Mini Nutritional Assessment, handgrip strength test) was conducted of all participants. The primary outcome was the Z score of IC, secondary outcomes were VO2max and SFT subparameters. The study was registered in the Protocol Registry and Results System (Clinicaltrials.gov PRS) with the registration number NCT05958745.

RESULTS

90 participants successfully completed the study, with 30 individuals in each of the AE, AE + RE, and C groups. By the end of the 12th week, the arm curl score was significantly higher in the AE + RE compared to the C (mean difference: 3.96, 95 % CI= 2.47 to 5.46, p = 0.01). There were significant differences in chair stand, two-minute step, 8-foot up-and-go, chair sit and reach, and back scratch tests in both AE and AE + RE compared to C. AE and AE + RE exhibited significantly higher shuttle test distances and VO2max values compared to the C (p < 0.0001). AE + RE achieved a significantly higher total IC score than the C (mean difference: 0.59, %95 CI= -0.07 to 1.26, p = 0.025).

CONCLUSION

In this study within the green exercise concept, both AE and AE + RE led to similar improvements in strength, flexibility, mobility, endurance, and aerobic capacity. Notably, AE + RE demonstrated an additional benefit by increasing the total IC, while AE alone did not exhibit the same effect.

Multidomain interventions for sarcopenia and cognitive flexibility in older adults for promoting healthy aging: a systematic review and meta-analysis of randomized controlled trials

The global population is undergoing rapid aging, making physical activity a crucial element in preventing mortality and lowering the risk of Alzheimer's disease. Age-related declines in muscle mass and cognitive abilities significantly contribute to frailty and dependency. Thus, this study focuses on a meticulous analysis of the protective effects of multidomain interventions, an emerging resource combating age-related declines. It seeks to underscore their profound impact on cognitive flexibility and sarcopenia, highlighting their pivotal role in mitigating the adverse effects of aging. To identify relevant randomized controlled trials up to November 2023, we reviewed eight online academic databases, following PERSiST guidelines, PRISMA reporting system, and PICOs criteria. Meta-analyses on selected functional outcomes utilized a random-effects model, including the Timed Up and Go Test, Sit to Stand Test, Victoria Stroop Test, and Trail Making Test. Out of 2082 scrutinized articles, 17 were included in the systematic review, and 8 in the meta-analysis. Positive effects (p = 0.05, I2 = 57%; 95% CI - 0.63 to - 0.05) were observed in cognitive flexibility for certain interventions. Similarly, interventions addressing muscle strength demonstrated improvements in the Sit to Stand Test for the exercise group compared to the control group (p = 0.02, I2 = 0%; 95% CI - 0.63 to - 0.05). These findings underscore the importance of incorporating physical activity as a primary component of public health interventions for promoting healthy aging and reducing the burden of age-related diseases. Future interventions may explore more homogeneous approaches and evaluate the impact of thrice multidomain weekly sessions.

Intrinsic Capacity and Its Biological Basis: A Scoping Review

BACKGROUND

In 2015, the World Health Organization (WHO) introduced the concept of intrinsic capacity (IC) to define healthy aging based on functional capacity. In this scoping review, we summarized available evidence on the development and validation of IC index scores, the association of IC with health-related factors, and its biological basis. The review specifically focused on identifying current research gaps, proposed strategies to leverage biobank datasets, and opportunities to study the genetic mechanisms and gene-environment interactions underlying IC.

METHODS

The literature search was conducted across six databases, including PubMed, CINAHL, Web of Science, Scopus, AgeLine, and PsycINFO, using keywords related to IC.

RESULTS

This review included 84 articles, and most of them (n=38) adopted the 5-domains approach to operationalize IC, utilizing correlated five factors or bifactor structures. Intrinsic capacity has consistently shown significant associations with socio-demographic and health-related outcomes, including age, sex, wealth index, nutrition, exercise, smoking, alcohol use, ADL, IADL, frailty, multimorbidity, and mortality. While studies on the biological basis of the composite IC are limited, with only one study finding a significant association with the ApoE gene variants, studies on specific IC domains - locomotor, vitality, cognitive, psychological, and sensory suggest a heritability of 20-85% of IC and several genetic variants associated with these subdomains have been identified. However, evidence on how genetic and environmental factors influence IC is still lacking, with no available study to date.

CONCLUSION

Our review found that there was inconsistency in the use of standardized IC measurement tools and indicators, but the IC indices had shown good construct and predictive validity. Research into the genetic and gene-to-environment interactions underlying IC is still lacking, which calls for the use of resources from large biobank datasets in the future.

The overall and domain-specific quality of life of Chinese community-dwelling older adults: the role of intrinsic capacity and disease burden

Objective

This study aimed to investigate the impact of the different domains of intrinsic capacity (IC) and chronic disease burden on health-related quality of life (HRQoL) and domain-specific HRQoL in Chinese community-dwelling older adults.

Design

A cross-sectional observational study of a community-based cohort.

Participants

We evaluated Chinese older adults (n = 429, mean age, 72.91 ± 7.014 years; female proportion, 57.30%).

Measurements

IC contains five domains, namely locomotion, vitality, cognition, psychological, and sensory capacity. Locomotion dysfunction was defined as grip and/or gait decline. Vitality decline was defined if two of the following three parameters were present: fatigue, physical inactivity, and weight loss or overweight. Cognition was classified into normal cognition, pre-mild cognitive impairment (pre-MCI), and MCI according to the normative z-scores of the neuropsychological test battery. Psychological dysfunction was diagnosed based on depressive symptoms. Sensory dysfunction was defined as hearing and/or vision impairment. HRQoL was assessed using the AQoL-8D scale, which comprised physical (including independent living, senses, and pain) and psychosocial (including mental health, happiness, self-worth, coping, and relationships) dimensions. Low HRQoL (HRQoL score or subscores in the highest quintile) was used as a dependent variable in logistic regression analyses adjusted for demographic, health-related, and psychological confounders.

Results

Sensory impairment was an independent determinant of senses, and locomotion impairment was significantly associated with overall HRQoL, independent living, and pain in the physical dimension of HRQoL. Cognition was an independent determinant of the senses. Vitality was independently associated with overall HRQoL, senses, and pain in the physical dimension and mental health and relationships in the psychological dimension of HRQoL. The psychological domain of IC was independently associated with overall and domain-specific HRQoL apart from senses after adjustment for all confounders. The number of multimorbidities mainly had a significant impact on independent living after adjustment for all confounders.

Conclusion

IC domains and chronic disease burden had heterogeneous influences on overall and domain-specific HRQoL. The impairment of sensory and locomotion domains had a synergistic impact on the overall and physical dimensions of HRQoL. The vitality and psychological domains of IC had more profound effects on HRQoL. Older people with high morbidity might have a higher risk of poor independent living.

Effect of home-based group conversation intervention using smartphone application on cognitive health and psychological well-being of older adults with subjective cognitive concerns in Japan: a randomized controlled trial protocol

Background

Social activity is a key component in the prevention of cognitive decline. However, face-to-face social intervention has limited accessibility. To address this issue, we developed the "Photo-Integrated Conversation Moderated by Application" (PICMOA), a home-based group conversation intervention using smartphones. This paper introduces the PICMOA intervention and the protocol of the ongoing randomized controlled trial (RCT), which aims to evaluate the effects of PICMOA on the cognitive functioning and psychological well-being of Japanese community dwelling older adults at the risk of cognitive function decline.

Methods

This study uses an RCT design in two parallel group trials with 1:1 allocation. The participants are community dwelling older adults aged 65 years and above, living in an urban city in Japan, with subjective cognitive concerns. In total, 81 participants were allocated to the intervention or control groups. The intervention group receives 30 min of weekly PICMOA sessions at their home for 12 weeks. The PICMOA intervention consists of (1) a photo preparation period before the session and (2) a structured group conversation session talking about the photos that participants took according to a specific theme. The control group receives 30 min of weekly health education videos on a tablet device. The primary outcome is cognitive functioning at pre- and post-phases of the 12-week intervention measured using the Telephone Interview for Cognitive Status in Japanese, semantic and phonemic fluency tests, and the Digit Span Forward and Backward tests. The secondary outcomes are psychological and social aspects including mental status, well-being, loneliness, and social support.

Discussion

Interest is growing in internet-based activities for preventing social isolation. However, the effect of remote conversation interventions on cognitive functioning remains unclear. This study addresses this issue and provides a new avenue of social participation for older adults.

Clinical trial registration

https://www.umin.ac.jp/ctr/, identifier: UMIN000047247.

The Association between Physical Activity and Intrinsic Capacity in Chinese Older Adults and Its Connection to Primary Care: China Health and Retirement Longitudinal Study (CHARLS)

BACKGROUND

In 2015, intrinsic capacity (IC) was proposed by the WHO as a new measure for healthy aging. Evidence has shown that physical activity (PA) benefits the physical and mental health of older adults. However, the association between PA and IC among older adults was not well evaluated or reported. This study aims to investigate the association between PA and general and specific IC among Chinese older adults.

METHOD

The study included individuals aged 60 and above from the China Health and Retirement Longitudinal Study in 2015. The IC scores were constructed based on the WHO concept of five domains: psychological capacity, cognition, locomotion, vitality, and sensory abilities. Total PA and leisure PA were measured based on different activity purposes. Linear mixed-effects models and generalized linear mixed-effects models were developed to assess the associations between PA and IC.

RESULTS

A total of 3359 participants were included in this study. Older adults who reported some PA were associated with a higher composite IC score, with a mean difference of 0.14 (95% CI: 0.09-0.18, p < 0.001) compared to those who reported no PA. In terms of leisure PA, physically active adults had a higher composite IC score with a mean difference of 0.06 (95% CI: 0.03-0.09, p < 0.001). Older adults with a high level of leisure PA also had a significantly higher composite IC score (diff. in mean = 0.07, 95% CI: 0.01-0.13, p < 0.05) compared to those with low-level leisure PA. In addition, PA was positively and significantly associated with three specific IC domains: locomotion, cognition, and vitality.

CONCLUSIONS

Improving both general and leisure PA can be an effective way to prevent the decline in IC among older adults, thus reducing the personal and public load of primary healthcare for aging countries such as China.

Measurements of Intrinsic Capacity in Older Adults: A Scoping Review and Quality Assessment

OBJECTIVES

This review summarizes the measurements of intrinsic capacity in 5 domains across different studies and evaluates the quality of research papers.

DESIGN

Scoping review of papers written in English and Chinese published in peer-reviewed journals.

SETTING AND PARTICIPANTS

The intrinsic capacity of older adults was assessed using the multidomain structure (Cognition, Locomotion, Psychological, Sensory and Vitality) proposed by the World Health Organization.

METHODS

We searched PubMed, MEDLINE, and Web of Science for papers in English, and CNKI, CBM for papers written in Chinese published until September 13, 2022. Both cross-sectional and cohort studies of multidomain measurements of intrinsic capacity were included. Three independent reviewers appraised the quality of studies, and Cohen's kappa was calculated to determine interrater reliability. Data were listed by author, year, setting, country, age range and number of participants, measurement and calculation of intrinsic capacity, and data acquisition method.

RESULTS

We included 53 studies. Twenty-one studies were of high quality, 31 studies were of moderate quality, and 1 study was of low quality. Measurements of intrinsic capacity and derivation of the summative index score were heterogeneous. Intrinsic capacity was usually assessed in 4 or 5 domains. Sensory was the most frequently overlooked domain or subdivided into vision and hearing in some studies. Indicators of vitality were the most heterogeneous. We also found consistency in heterogeneous measurements. The most common measurements of cognition, locomotion, and psychological capacity were the Mini-Mental State Examination, Short Physical Performance Battery, and Geriatric Depression Scale respectively. Self-reported questionnaires were commonly adopted in sensory domain. The Mini-Nutritional Assessment and grip strength were the most measured indicators of vitality.

CONCLUSIONS AND IMPLICATIONS

The focus on capacity and disease should be balanced to better promote healthy aging in older adults. Heterogeneity of intrinsic capacity measurements underscores the need for consensus about standardized measurements and calculation procedures.

Effects of a 12-week Vivifrail exercise program on intrinsic capacity among frail cognitively impaired community-dwelling older adults: secondary analysis of a multicentre randomised clinical trial

INTRODUCTION

The World Health Organisation recently defined the construct of intrinsic capacity (IC), a function-based marker of older adult's health encompassing all mental and physical capacities of the individual. Multicomponent physical exercise (MCE) is a potential intervention capable to maintain/increase IC at older age; however, evidence is scarce on the effects of MCE on IC in cognitively impaired pre-frail/frail older adults.

METHODS

Secondary analyses of a randomised clinical trial. One hundred and eighty-eight older outpatients (age = 84.06 ± 4.77, 70.2% women) presenting with pre-frailty/frailty (according to Fried Criteria) and mild cognitive impairment (MCI)/mild dementia were recruited in the Geriatric clinics of three tertiary hospitals in Spain. Subjects were randomised to participate in the 12-week home-based individualised Vivifrail MCE or usual care. An IC index was created based on the z-score of the locomotion (Short Physical Performance Battery), cognitive (Montreal Cognitive Assessment), psychology (15-item Geriatric Depression Scale Yesavage) and vitality (handgrip strength) domains.

RESULTS

After the 3-month intervention, linear mixed models showed significant between-group differences in the evolution of the IC composite score (β=0.48; 95% confidence interval [CI] = 0.24, 0.74; P < 0.001), IC Locomotion (β = 0.42; 95% CI = 0.10, 0.74; P < 0.001), IC Cognition (β = 0.45; 95% CI = 0.03, 0.87; P < 0.05) and IC Vitality domains (β = 0.50; 95% CI = 0.25, 0.74 at 3-month) favouring the MCE group.

CONCLUSIONS

The 12-week Vivifrail multicomponent exercise program is an effective strategy to enhance IC, especially in terms of locomotion, cognition and vitality IC domains in community-dwelling older adults with pre-frailty/frailty and MCI/mild dementia, compared to usual care.

WHO working definition of vitality capacity for healthy longevity monitoring

Intrinsic capacity, a crucial concept in healthy ageing, is defined by WHO as "the composite of all the physical and mental capacities that an individual can draw on at any point in time". Vitality capacity is considered the underlying physiological determinant of intrinsic capacity. To advance the measurement and monitoring of vitality capacity, a working group of WHO staff members and twenty experts representing six WHO regions was convened to discuss and clarify the attributes of vitality capacity and to develop a clear working definition of the concept. Potential biomarkers to measure vitality capacity were identified, and the following consensual working definition was developed: vitality capacity is a physiological state (due to normal or accelerated biological ageing processes) resulting from the interaction between multiple physiological systems, reflected in (the level of) energy and metabolism, neuromuscular function, and immune and stress response functions of the body.

Exploring the conceptual framework and measurement model of intrinsic capacity defined by the World Health Organization: A scoping review

WHO has defined intrinsic capacity (IC) as the composite of all physical and mental capacities of an individual covering five subdomains: cognition, locomotion, sensory, vitality, and psychological. Despite this well accepted definition, the conceptual and measurement model of IC remains unclear, which hampers a standardized operationalization of the construct. We performed a scoping review to give a comprehensive overview of the extent to which the current literature of IC addresses and assumes the conceptual framework and measurement model of IC as reflective or formative. For inclusion, we considered all types of articles that were published in peer-reviewed journals except for protocol articles. A systematic search of 6 databases from different disciplines led to the inclusion of 31 papers. We found inconsistency and gaps in the descriptions of IC. Most of the papers did not define the measurement model. In the conceptual background and validation articles, we identified descriptions of both reflective and formative measurement models while in empirical studies applying IC measurements the underlying assumptions remained mainly unclear. Defining a measurement model is not merely a theoretical matter but influences the operationalization and validation processes of the construct. This study raised questions about the most fundamental features of the IC construct and discusses whether IC should be considered as an underlying latent trait of all capacities (reflective construct) or an aggregate summary measure of the subdomain capacities (formative construct).

Intrinsic Capacity Declines with Elevated Homocysteine in Community-Dwelling Chinese Older Adults

Purpose

Intrinsic capacity (IC) reflects the overall health status of older adults and has great public health significance. But few studies described the related biomarkers for IC. The aim of this study was to investigate the association between homocysteine (Hcy) and IC in older adults.

Participants and Methods

This cross-sectional study included 1927 community-dwelling Chinese older adults aged 60–98 years from May 2020 to December 2020. Data were collected through interviews, physical examinations, and laboratory tests. IC involved five domains of cognition, locomotion, sensory, vitality, and psychology evaluated by the Mini-cog scale, 4-m walk test, self-reported visual and hearing conditions, MNA-SF scale, and GDS-4 scale, respectively. The score of each domain dichotomized as 0 (normal) and 1 (impaired) was added together to an IC total score. Low IC was defined as a score of 3–5, and high IC as 0–2. Hcy was measured by a two-reagent enzymatic assay. A restricted cubic spline regression model was used to explore the non-linear relationship between Hcy and low IC.

Results

Hcy was higher in the low IC group than in the high IC group. Restricted cubic spline analysis revealed a J-shaped nonlinear association between Hcy and low IC. The risk of IC decline was slowly decreased until 8.53 µmol/L of Hcy (OR=0.753, 95% CI=0.520–1.091, P=0.132), and increased with elevations of per 5 µmol/L Hcy afterwards (OR=1.176, 95% CI=1.059–1.327, P=0.005). Among the five domains of IC, Hcy had ORs of 1.116 (1.009–1.247) for cognition impairment, 1.167 (1.055–1.305) for vitality, and 1.160 (1.034–1.303) for psychology per 5 µmol/L increase in Hcy above the change point. Additional sensitivity analysis also demonstrated the nonlinear association between Hcy and low IC.

Conclusion

Hcy had a J-shaped association with low IC. Higher Hcy (Hcy ≥8.53µmol/L) might provide clinical implications for early identifying the risk of low IC.

Defining and assessing intrinsic capacity in older people: A systematic review and a proposed scoring system

INTRODUCTION

The World Health Organization has introduced the term 'intrinsic capacity' (IC) as a marker of healthy ageing. However, controversy exists on the definition and assessment of IC. We aimed to review the definitions and methods used for the assessment of IC in older adults. In addition, we proposed a new IC scoring method.

METHODS

A systematic search was performed in PubMed, Web of Science, Cochrane Library, Scopus and SPORTDiscus (up to February 10th, 2022) for studies assesing IC in older adults (>60 years).

RESULTS

Thirty-three studies were included. There is overall consensus on the definition of IC as well as on its different dimensions, that is: locomotion, vitality, sensory, cognition and psychological. However, the methods for assessing each of these five dimensions differ substantially across studies and there is no consensus on the best method to compute an eventual global compound score to evaluate IC taking into account all its different dimensions.

CONCLUSIONS

The IC represents a highly relevant clinical concept that has been unfortunately underutilized. We propose a standardization for the assessment of each dimension of IC, with a global 0 (worst) to 10 (highest) score.

Screening intrinsic capacity and its epidemiological characterization: a secondary analysis of the Mexican Health and Aging Study

Objective.

To describe the levels of intrinsic capacity and those factors related to its decline in Mexican older adults, using the Mexican Health and Aging Study.

Methods.

This is a cross-sectional secondary analysis of the 2015 data of the Mexican Health and Aging Study, including adults aged 50 years and above. Selected questions were included to represent each domain of intrinsic capacity screening: cognition, depression, hearing, vision, anorexia, weight loss, and mobility. Sociodemographic characteristics, psychosocial factors, and health conditions were included to assess their association with intrinsic capacity. Further categories were established to assess not only individual characteristics but also different groupings. Along with descriptive statistics, multinomial regression models were performed.

Results.

From a total of 12 459 adults aged 50 years and above, 54.7% were women and the average age was 71.2 years; 87.8% of the individuals had at least one intrinsic capacity domain affected, and mobility had the highest frequency (47.6%). All domains showed a trend of increasing with age and were higher among women. Self-rated health, chronic diseases, number of visits to a physician in the last year, and ≥2 affected activities of daily living were consistently associated with more intrinsic capacity domains affected.

Conclusions.

Decreased levels of intrinsic capacity in Mexican older people are associated with less schooling, self-rated health, chronic diseases, visits to a physician, and activities of daily living.

Intrinsic Capacity: Validation of a New WHO Concept for Healthy Ageing in a Longitudinal Chinese Study

BACKGROUND

The World Health Organization has proposed a model of healthy aging built around the concept of functional ability, comprising an individual's intrinsic capacity, the physical and social environment they occupy, and interactions between the two. However, these constructs have been poorly defined. We examined the structure of intrinsic capacity in a representative sample of the Chinese population aged 60 years and over and assessed its value in predicting declining performance in instrumental activities of daily living (IADLs) and activities of daily living (ADLs) using similar methods to a construct validation previously undertaken in an English cohort.

METHODS

De-identified data were accessed on 7643 participants of the China Health and Retirement Longitudinal Study (CHARLS) 2011 and 2013 waves. Incrementally related structural equation modelling was applied, including exploratory and confirmatory factor analysis, and path analysis. Multiple linear regression tested construct validity, and simple and serial mediation models assessed predictive validity.

RESULTS

Factor loadings for the models showed a clear structure for intrinsic capacity: one general factor with five subfactors - locomotor, cognitive, psychological and sensory capacities, and vitality (reflecting underlying physiologic changes). Intrinsic capacity predicted declining performance in both IADLs (Standardized Coefficient (SE) -0.324 (0.02), p<0.001) and ADLs (-0.227 (0.03), p<0.001), after accounting for age, sex, education, wealth and number of chronic diseases. Each characteristic was associated with intrinsic capacity, providing strong construct validity.

CONCLUSIONS

Assessment of intrinsic capacity provides valuable information on an individual's subsequent functioning beyond that afforded by age, other personal factors and multimorbidity.

Cross-sectional study examining the status of intrinsic capacity decline in community-dwelling older adults in China: prevalence, associated factors and implications for clinical care

OBJECTIVES

Intrinsic capacity (IC) was proposed by the WHO as a new concept for capturing an individual's functional capacities across their lifetime. We aimed to investigate the prevalence and factors associated with IC decline and examine associations between IC and adverse outcomes among community-dwelling older adults in China.

DESIGN

A cross-sectional study.

SETTING

Community, China.

PARTICIPANTS

Data were derived from the China Comprehensive Geriatric Assessment Study, a population-based nationally representative sample. IC comprises of five domains: locomotion, cognition, vitality, sensory and psychology. Participants were deemed to have IC decline if they showed a decline in any of the five domains. Sociodemographic characteristics, chronic diseases, geriatric syndromes and adverse outcomes were also examined.

RESULTS

Of the 5823 community-dwelling participants aged 60-98 years, 2506 had IC decline (weighted 39.9%): 57.7% in western, 38.3% in northern, 33.7% in northwest, 36.1% in middle, 16.9% in eastern and 19.8% in northeast China. The number of participants with decline in the locomotion, cognition, vitality, sensory and psychological domains were 1039 (17.8%), 646 (11.1%), 735 (12.6%), 824 (14.2%) and 713 (12.2%), respectively. Age, northern residence, low education, being unmarried, low income, less exercise, less meat intake, insomnia, memory loss, urinary incontinence, constipation, slowness, chronic obstructive pulmonary disease and osteoarthritis were related to IC decline. After adjusting for age, sex, area, district, marriage, education, waist-hip ratio, smoking, alcohol consumption, exercise, income and chronic diseases, IC decline was independently associated with risk of frailty, disability, falls, fractures and immobility.

CONCLUSION

The prevalence of IC decline in China is high. IC decline was significantly associated with adverse outcomes, after adjustment for related variables. Efforts promoting IC to delay functional dependence should focus on modifiable factors, including negative social factors, poor lifestyle, chronic diseases and geriatric syndromes.