Predicting late-life disability and death by the rate of decline in physical performance measures

Innovations in pharmacovigilance studies of medicines in older people

Pharmacovigilance is defined by the World Health Organization as "the science and activities relating to the detection, assessment, understanding and prevention of adverse effects or any other medicine/vaccine related problem". Pharmacovigilance studies are critical for detecting and assessing adverse events of medicines that may not have been observed in clinical trials. This activity is especially important in older people who are often excluded from clinical trials as they have multiple chronic conditions and use multiple medicines for longer durations than the clinical trials. In this narrative review we describe innovative methods in pharmacovigilance studies of medicines in older people that leverage the increasing availability of digital health technologies, electronic health records and real-world health data to identify and quantify medication related harms in older people.

The "Can Do, Do Do" Framework Applied to Assess the Association between Physical Capacity, Physical Activity and Prospective Falls, Subsequent Fractures, and Mortality in Patients Visiting the Fracture Liaison Service

The "can do, do do" framework combines measures of poor and normal physical capacity (PC, measured by a 6 min walking test, can do/can't do) and physical activity (PA, measured by accelerometer, do do/don't do) into four domains and is able to categorize patient subgroups with distinct clinical characteristics, including fall and fracture risk factors. This study aims to explore the association between domain categorization and prospective fall, fracture, and mortality outcomes. This 6-year prospective study included patients visiting a Fracture Liaison Service with a recent fracture. Outcomes were first fall (at 3 years of follow-up, measured by fall diaries), first subsequent fracture, and mortality (at 6 years). Cumulative incidences of all three outcomes were calculated. The association between domain categorization and time to the three outcomes was assessed by uni- and multivariate Cox proportional hazard analysis with the "can do, do do" group as reference. The physical performance of 400 patients with a recent fracture was assessed (mean age: 64 years; 70.8% female), of whom 61.5%, 20.3%, and 4.9% sustained a first fall, sustained a subsequent fracture, or had died. Domain categorization using the "can do, do do" framework was not associated with time to first fall, subsequent fracture, or mortality in the multivariate Cox regression analysis for all groups. "Can't do, don't do" group: hazard ratio [HR] for first fall: 0.75 (95% confidence interval [CI]: 0.45-1.23), first fracture HR: 0.58 (95% CI: 0.24-1.41), and mortality HR: 1.19 (95% CI: 0.54-6.95). Categorizing patients into a two-dimensional framework seems inadequate to study complex, multifactorial outcomes. A personalized approach based on known fall and fracture risk factors might be preferable.

Terminal Decline in Physical Function in Older Adults

BACKGROUND

It is currently unclear whether (and when) physical function exhibits a terminal decline phase, that is, a substantial acceleration of decline in the very last years before death.

METHODS

702 deceased adults aged 70 years and older from the Yale PEP Study provided 4 133 measurements of physical function (Short Physical Performance Battery, SPPB) up to 20 years before death. In addition, continuous gait and chair rise subtest scores (in seconds) were assessed. Generalized mixed regression models with random change points were used to estimate the onset and the steepness of terminal decline in physical function.

RESULTS

Decline accelerated in the last years of life in all 3 measures of physical function. The onset of terminal decline occurred 1 year before death for the SPPB, and at 2.5 and 2.6 years before death for chair rise and gait speed test scores, respectively. Terminal declines in physical function were 6-8 times steeper than pre-terminal declines. Relative to those whose condition leading to death was frailty, participants who died from dementia and cancer had an up to 6 months earlier and 3 months later onset of terminal decline in SPPB, respectively.

CONCLUSIONS

Terminal decline in physical function among older adults is comparable to the more established terminal decline phenomenon in cognition. Our results provide additional evidence of late-life rapid decline in physical function due to impending death.

Improving Strength and Fatigue Resistance in Post-Polio Syndrome Individuals with REAC Neurobiological Treatments

Post-Polio Syndrome (PPS) is a chronic condition characterized by the emergence of new symptoms and functional decline in individuals who previously had polio. Despite advances in medical understanding, management of PPS remains challenging. This study aimed to evaluate the use of neurobiological modulation treatments using Radio Electric Asymmetric Conveyer (REAC) technology on fatigue and muscle strength. An open-label study was conducted with 17 patients submitted to four neuromodulation protocols: Neuro Postural Optimization (NPO), Neuro Psycho Physical Optimization (NPPO), Neuro Psycho Physical Optimization-Cervico Brachial (NPPO-CB), and Neuromuscular Optimization (NMO). The Time Up and Go (TUG) test, Handgrip Strength Test, and Revised Piper Fatigue Scale (RPFS) were used to assess participants' fatigue and muscle strength, being applied at the beginning and end of each protocol. The results obtained from the improvement in strength, physical endurance, and particularly the RPFS behavioral dimension, affective dimension, and psychological sensory dimension, through the utilization of REAC neurobiological modulation treatments, highlight this correlation. These results suggest that these treatments could be considered as a potential therapeutic approach for PPS.

Trajectories of Physical Function and Behavioral, Psychological, and Social Well-Being in a Cohort of Swedish Older Adults

Background and Objectives

Successful aging has been described as a multifactorial and dynamic process. The aims of the study were to detect aging trajectories of physical function and behavioral, psychological, and social well-being; and to explore the correlations between functional versus well-being trajectories by age group.

Research Design and Methods

Data were gathered from the Swedish National Study on Aging and Care in Kungsholmen (N = 1,375). Subjects' physical function was assessed through walking speed and chair-stand tests, behavioral well-being through participation in mental and physical activities, psychological well-being through life satisfaction and positive affect, and social well-being through social connections and support. All exposures were standardized (z-scores). Linear mixed models were used to estimate trajectories of physical function and well-being over a 12-year follow-up.

Results

The steepest declines were seen for physical function (relative change [RC] in z-scores across ages; RC = 3.01), followed by behavioral well-being (RC = 2.15), psychological well-being (RC = 2.01), and social well-being (RC = 0.76). Correlations between physical function and the different well-being domains were weak, especially for slopes. Stronger intercept correlations were observed among the oldest-compared to the youngest-old, especially with behavioral (r = 0.39 vs r = 0.24) and psychological (r = 0.33 vs r = 0.22) well-being.

Discussion and Implications

Physical function declines the fastest throughout aging. The different well-being domains decline at a slower rate, which may be a possible sign of compensation against age-related functional decline, especially among the youngest-old, for whom discordances between physical function and the different well-being domains were more common.

Association of Handgrip Strength in Various Disabilities in Korean Adults over 50 Years Old: A Nationwide Cross-Sectional Study

Several studies have shown an association between low hand grip strength (HGS) and functional limitations. This study aims to elucidate the association between HGS and functional limitations. We used the nationwide health examination data and included 13,517 Korean adults that were aged ≥ 50 years. We measured HGS using digital dynamometer and the maximum value of the dominant hand was divided into quartiles for the analysis. Functional limitations were assessed by using self-administered questionnaires. We categorized the 24 reported causes of functional limitations into musculoskeletal, cardiometabolic, neuropsychiatric, cancers, and others. In multiple regression analysis, the functional limitations tended to increase as HGS was lowered in both sexes. When analyzing according to the reasons of functional limitations, the ORs for functional limitations due to cardiometabolic problem tended to increase as the HGS decreased in men (p for trend = 0.039). Similar trends were observed in neuropsychiatric problem in women (p for trend = 0.002) and other problems in both men and women (p for trend = 0.014 in men, p for trend = 0.004 in women). No significant trends were observed for musculoskeletal problems and cancer in both men and women. The functional limitations were inversely associated with HGS, which were inconsistent according to different etiologies of functional limitations.

Muscle Strength and Physical Performance Are Associated With Risk of Postfracture Mortality But Not Subsequent Fracture in Men

Muscle strength and physical performance are associated with incident fractures and mortality. However, their role in the risk of subsequent fracture and postfracture mortality is not clear. We assessed the association between muscle strength (grip strength) and performance (gait speed and chair stands time) and the risk of subsequent fracture and mortality in 830 men with low-trauma index fracture, who participated in the Osteoporotic Fractures in Men (MrOS) USA Study and had their index measurements assessed within 5 years prior to the index fracture. The annual decline in muscle strength and performance following index fracture, estimated using linear mixed-effects regression, was also examined in relation to mortality. The associations were assessed using Cox proportional hazards models adjusted for age, femoral neck bone mineral density (FN BMD), prior fractures, falls, body mass index (BMI), index fracture site, lifestyle factors, and comorbidities. Over a median follow-up of 3.7 (interquartile range [IQR], 1.3-8.1) years from index fracture to subsequent fracture, 201 (24%) men had a subsequent fracture and over 5.1 (IQR, 1.8-9.6) years to death, and 536 (65%) men died. Index measurements were not associated with subsequent fracture (hazard ratios [HRs] ranging from 0.97 to 1.07). However, they were associated with postfracture mortality. HR (95% confidence interval [CI]) per 1 standard deviation (1-SD) decrement in grip strength: HR 1.12 (95% CI, 1.01-1.25) and gait speed: HR 1.14 (95% CI, 1.02-1.27), and 1-SD increment in chair stands time: HR 1.08 (95% CI, 0.97-1.21). Greater annual declines in these measurements were associated with higher mortality risk, independent of the index values and other covariates. HR (95% CI) per 1-SD annual decrement in change in grip strength: HR 1.15 (95% CI, 1.01-1.33) and in gait speed: HR 1.38 (95% CI, 1.13-1.68), and 1-SD annual increment in chair stands time: HR 1.28 (95% CI, 1.07-1.54). Men who were unable to complete one or multiple tests had greater risk of postfracture mortality (24%-109%) compared to those performed all tests. It remains to be seen whether improvement in these modifiable factors can reduce postfracture mortality. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Influence of Cardiovascular Risk Burden on Motor Function Among Older Adults: Mediating Role of Cardiovascular Diseases Accumulation and Cognitive Decline

Purpose

This study aimed to investigate the association of the cardiovascular risk burden assessed by the Framingham General Cardiovascular Risk Score (FGCRS) with the trajectories of motor function over time and to assess the mediating effects of cardiovascular diseases (CVDs) accumulation and cognitive decline in such association.

Methods

In Rush Memory and Aging Project, a total of 1,378 physical health participants (mean age: 79.3 ± 7.3 years) were followed up for up to 22 years. FGCRS at baseline was assessed and categorized into tertiles (lowest, middle, and highest). Global motor function (including dexterity, gait, and hand strength) was assessed annually with 10 motor tests. CVDs (including stroke, congestive heart failure, and other heart diseases) were ascertained at baseline and follow-ups, and the number of CVDs accumulation over time was assessed. Global cognitive function was tested annually by 19 tests. Data were analyzed using the linear mixed-effects models and mediation analysis.

Results

At baseline, FGCRS ranged from 4 to 28 (mean score: 15.6 ± 3.7). Over the follow-up (median: 5.3 years; interquartile range: 2.9-9.0 years), in multi-adjusted mixed-effects models, the highest FGCRS was associated with faster decline in global motor function (β = -0.0038; 95% confidence interval [CI]: -0.0069 to -0.0008), dexterity (β = -0.0056; 95% CI: -0.0093 to -0.0020), gait (β = -0.0039; 95% CI: -0.0077 to -0.0001), and hand strength (β = -0.0053; 95% CI: -0.0098 to -0.0008) compared with the lowest tertile. In mediation analysis, CVDs accumulation and cognitive decline mediated 8.4% and 42.9% of the association between FGCRS and global motor function over time, respectively.

Conclusion

Higher cardiovascular risk burden is associated with a faster decline in motor function including dexterity, gait, and hand strength. CVDs accumulation and cognitive decline may partially mediate the association between cardiovascular risk burden and global motor function decline.

Frequency of data collection and estimation of trajectories of physical functioning and their associations with survival in older men: analyses of longitudinal data from the Manitoba Follow-Up Study

OBJECTIVE

In studies of trajectories of physical functioning among older people, the data cannot be measured continuously, but only at certain time points in prespecified cycles. We examine how data collection cycles can affect the estimation of trajectories and their associations with survival.

STUDY DESIGN AND SETTING

Longitudinal data from the Manitoba Follow-Up Study (MFUS), with 12 measurements collected annually from 2004 to 2015, are analysed using a summary measures of physical functioning from the Short Form-36 questionnaire. Based on the joint models of the functioning trajectories and risk of death, we compare the estimations among models using different frequency of data collection (annually, biennially and triennially).

RESULTS

Our 2004 baseline includes 964 men who were survivors from the original MFUS cohort with mean age of 84 years and range between 75 and 94 years. Results from analysis of annual data indicate that the mean physical functioning is significantly decreasing over time. Further, the rate of decline is increasing over time. The current value of physical functioning is significantly associated with the hazard of death (p<0.001), whereas the association between the change rate and mortality is marginally significant (p<0.10). Results from analysis of biennial and triennial data reveal similar trajectory patterns of physical functioning, but could not reveal the association between the change rate of physical functioning and mortality. The frequency of data collection also impacts substantially on the estimation of heterogeneity of functioning trajectory. The prediction of mortality risk obtained using annual measurements of physical functioning are better than using biennial or triennial measurements, while the predictions obtained using biennial or triennial measurements are almost equivalent.

CONCLUSION

The impact of frequency of data collection depends on the shape of functional trajectories and its linking structure to survival outcome.

Static and Dynamic Pain Sensitivity in Adults With Persistent Low Back Pain: Comparison to Healthy Controls and Associations With Movement-evoked Pain Versus Traditional Clinical Pain Measures

OBJECTIVES

Despite its impact, individual factors associated with persistent low back pain (LBP) remain poorly understood. This study investigated static and dynamic pain sensitivity in adults with persistent LBP versus pain-free controls; and investigated associations between pain sensitivity and 3 clinical pain measures: recalled, resting, and movement-evoked pain (MEP).

MATERIALS AND METHODS

A lifespan sample of 60 adults with persistent LBP and 30 age-matched/sex-matched controls completed 4 laboratory sessions. Static pain sensitivity (pressure pain threshold [PPT], heat pain threshold) and dynamic pain sensitivity (heat pain aftersensations [AS], temporal summation [TS] of second heat pain) were measured. Demographic and clinical factors collected were education, global cognition, and perceived health. Resting and recalled pain were measured via questionnaire, and MEP via the Back Performance Scale.

RESULTS

LBP participants demonstrated lower PPT remotely (hand; F1,84=5.34, P=0.024) and locally (low back; F1,84=9.55, P=0.003) and also had higher AS (F1,84=6.01, P=0.016). Neither static nor dynamic pain sensitivity were associated with recalled pain (P>0.05). However, static pain sensitivity (local PPT) explained an additional 9% variance in resting pain, while dynamic pain sensitivity (AS, TS) explained an additional 10% to 12% variance in MEP.

DISCUSSION

This study characterized pain sensitivity measures among individuals with persistent LBP and suggests static pain sensitivity plays a larger role in resting pain while dynamic pain sensitivity plays a larger role in MEP. Future studies will confirm these relationships and elucidate the extent to which changes in static or dynamic pain sensitivity predict or mediate clinical pain among adults with persistent LBP.

Stride Length Predicts Adverse Clinical Events in Older Adults: A Systematic Review and Meta-Analysis

Background: This meta-analysis aims to estimate the power of walking stride length as a predictor of adverse clinical events in older adults. Methods: We searched all electronic databases until April 2021 for studies reporting stride length and other spatial gait parameters, including stride velocity, stride width, step width and stride variability, and compared them with clinical outcomes in the elderly. Meta-analyses of odds ratios (ORs) of effects of stride length on clinical outcomes used the generic inverse variance method and random model effects. Clinical outcomes were major adverse events (MAEs), physical disability and mortality. Results: Eleven cohort studies with 14,167 patients (mean age 75.4 ± 5.6 years, 55.8% female) were included in the analysis. At 33.05 months follow up, 3839 (27%) patients had clinical adverse events. Baseline stride length was shorter, WMD −0.15 (−0.19 to −0.11, p < 0.001), and stride length variability was higher, WMD 0.67 (0.33 to 1.01, p < 0.001), in fallers compared to non-fallers. Other gait parameters were not different between the two groups (p > 0.05 for all). Short stride length predicted MAE OR 1.36 (95% CI; 1.19 to 1.55, p < 0.001), physical disability OR 1.26 (95% CI; 1.11 to 1.44, p = 0.004) and mortality OR 1.69 (95% CI; 1.41 to 2.02, p < 0.001). A baseline normalized stride length ≤ 0.64 m was more accurate in predicting adverse clinical events, with summary sensitivity 65% (58–71%), specificity 72% (69–75%) and accuracy 75.5% (74.2–76.7%) compared to stride length variability 5.7%, with summary sensitivity 66% (61–70%), specificity 56% (54–58%) and accuracy 57.1% (55.5–58.6%). Conclusion: The results of this meta-analyses support the significant value of stride length for predicting life-threatening clinical events in older adults. A short stride length of ≤0.64 m accurately predicted clinical events, over and above other gait measures.

Non-Invasive Biomarkers of Musculoskeletal Health with High Discriminant Ability for Age and Gender

A novel approach to ageing studies assessed the discriminatory ability of a combination of routine physical function tests and novel measures, notably muscle mechanical properties and thigh composition (ultrasound imaging) to classify healthy individuals according to age and gender. The cross-sectional study included 138 community-dwelling, self-reported healthy males and females (65 young, mean age ± SD = 25.7 ± 4.8 years; 73 older, 74.9 ± 5.9 years). Handgrip strength; quadriceps strength; respiratory peak flow; timed up and go; stair climbing time; anterior thigh tissue thickness; muscle stiffness, tone, elasticity (Myoton technology), and self-reported health related quality of life (SF36) were assessed. Stepwise feature selection using cross-validation with linear discriminant analysis was used to classify cases based on criterion variable derived from known effects of age on physical function. A model was trained and features selected using 126 cases with 0.92 accuracy (95% CI = 0.86–0.96; Kappa = 0.89). The final model included five features (peak flow, timed up and go, biceps brachii elasticity, anterior thigh muscle thickness, and percentage thigh muscle) with high sensitivity (0.82–0.96) and specificity (0.94–0.99). The most sensitive novel biomarkers require no volition, highlighting potentially useful tests for screening and monitoring effects of interventions on musculoskeletal health for vulnerable older people with pain or cognitive impairment.

Intrinsic Capacity as a Determinant of Physical Resilience in Older Adults

The traditional disease-oriented model of healthcare is inadequate to address the needs of the older population. Greater attention should be given to strategies that promote healthy aging. Recently proposed constructs of intrinsic capacity (IC) and physical resilience (PR) hold great potential to reshape geriatric medicine and aging research. These constructs accentuate the positive health attributes of older people in contrast to the popular frailty construct that is centered on functional deficits. IC was introduced by the World Health Organization (WHO) as a composite of all the physical and mental capacities. WHO has emphasized enhancement of IC throughout the life course so as to maintain functional ability in old age. PR, recently highlighted by the National Institute on Aging, is the ability to successfully cope with stressors. High levels of resilience can result in desirable clinical and functional outcomes after stressors. Therefore, it is important to understand the underlying physiology of PR and the risk factors contributing to diminished PR. The main goal of this article is to explore the potential relationship between IC and PR. Based on a classical theory of aging, we postulate that IC is a determinant of PR and is also a high-level integrative measure of physiologic reserve which is the fundamental factor underlying one's ability to withstand stressors. A major implication of our postulates is that even though IC is only one of the many determinants of PR, it could serve as an important intervenable target for enhancing resilience in older adults.

Changes in Physical Functioning as Short-Term Predictors of Mortality

OBJECTIVES

Both performance-based and self-reported measures of physical functioning are predictors of mortality. There has been relatively little research examining whether their changes predict mortality. This study examines whether 5-year changes in performance-based and self-reported measures of functioning predict subsequent mortality.

METHOD

Data are from the 2006 wave of the Social Environment and Biomarkers of Aging Study, 2011 wave of the Taiwan Longitudinal Study of Aging, and mortality follow-up through 2015. Gompertz proportional hazard models predict mortality from changes in ability to complete performance-based tests and changes in performance-based and self-reported functioning.

RESULTS

Incident inability to complete at least one performance-based test of functioning is associated with twice the risk of subsequent 4-year mortality. Conditional on the baseline measurement, a one standard deviation (SD) decline in grip strength is associated with a 61% increased risk of 4-year mortality; a one-SD decline in walking speed and a one-SD increase in self-reported limitations are both associated with around a 40% increased risk of 4-year mortality. Conditional on the most recent measurement of functioning, prior change is not significantly associated with subsequent mortality.

DISCUSSION

Repeated measures of performance-based and self-reported functioning are valuable in that they provide an updated measurement of functioning.

Disability trajectories in activities of daily living of elderly Chinese before death

This study aims to analyze the changes in activities of daily living (ADL) of the Chinese elderly before death, and to explore the heterogeneity in this process. Using data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS), we quantify disability trajectories of ADL using a group-based trajectory model and find that there are three types of disability trajectory for ADL. The elderly who differ by socioeconomic status, childhood experiences, health behaviors, ages and birth cohorts show significant differences in their disability trajectories. Long duration of disability is found to be more prevalent in older females and people with high socioeconomic status. Good and stable status of ADL is more common among males and people of low socioeconomic status, while the elderly in an early cohort who died at older ages were more likely to have experienced a long duration of disability. Selective and protective effects contribute to the observed differences in trajectories.

Causes of changes in basic activities of daily living in older adults with long-term care needs

OBJECTIVE

To elucidate basic activities of daily living (BADL) changes, and the causes, in older adults with long-term care needs.

METHODS

This retrospective study utilised long-term care insurance (LTCI) certification survey data from 2010 to 2017 in City A.

RESULTS

In decreasing likelihood of requiring assistance, BADL items were grooming, bathing, getting dressed/undressed, mobility, toilet hygiene, functional mobility and self-feeding. Cox proportional hazard regression indicated that age correlated with need for assistance for all BADL items. Male sex corresponded to needing assistance with BADL items other than grooming and functional mobility. Shared living corresponded to needing assistance with BADL items other than grooming and bathing. Visual acuity corresponded to needing assistance with grooming.

CONCLUSION

The most significant result was using survival curves to visualise the changes in BADL items of older adults with LTCI. These findings could help develop rehabilitation programs to prevent the need for BADL assistance in older adults.

Disability trajectories and mortality in older adults with different cognitive and physical profiles

Background

Cognitive and physical deficits independently raise the risk for negative events in older adults. Less is known about whether their co-occurrence constitutes a distinct risk profile. This study quantifies the association between cognitive impairment, no dementia (CIND), slow walking speed (WS) and their combination and disability and mortality.

Methods

We examined 2546 dementia-free people aged ≥ 60 years, part of the Swedish National study on Aging and Care in Kungsholmen (SNAC-K) up to 12 years. The following four profiles were created: (1) healthy profile; (2) isolated CIND (scoring 1.5 SD below age-specific means on at least one cognitive domain); (3) isolated slow WS (< 0.8 m/s); (4) CIND+ slow WS. Disability was defined as the sum of impaired activities of daily living and trajectories of disability were derived from mixed-effect linear regression models. Piecewise proportional hazard models were used to estimate mortality rate [hazard ratios (HRs)]. Population attributable risks of death were calculated.

Results

Participants with both CIND and slow WS had the worst prognosis, especially in the short-term period. They experienced the steepest increase in disability and five times the mortality rate (HR 5.1; 95% CI 3.5–7.4) of participants free from these conditions. Similar but attenuated results were observed for longer follow-ups. Co-occurring CIND and slow WS accounted for 30% of short-term deaths.

Conclusions

Co-occurring cognitive and physical limitations constitute a distinct risk profile in older people, and account for a large proportion of short-term deaths. Assessing cognitive and physical function could enable early identification of people at high risk for adverse events.

Electronic supplementary material

The online version of this article (10.1007/s40520-019-01297-1) contains supplementary material, which is available to authorized users.

Analyzing functional status and its correlates in Chinese centenarians: A cross-sectional study

Factors affecting independence in basic and instrumental activities of daily living have been established in older adults, but not centenarians. The purpose of this study was to examine the state and factors affecting activities of daily living independence in centenarians who resided in Guangxi Province, China. A cross-sectional design was used. Activities of daily living, physical activity, mobility, and physical performance were measured by the Population Study of ChINese Elderly study instruments, and demographics and cognition were assessed. Of the 228 participants, 57% were independent in basic activities of daily living and 5.7% in instrumental activities of daily living. Stepwise regression showed physical activity, cognition, calf circumference, and self-reported health were associated with basic activities of daily living. Physical activity, mobility, cognition, and physical performance were correlated with instrumental activities of daily living. In conclusion, the Chinese centenarians showed impaired instrumental activities of daily living but mostly maintained basic functioning. Physical activity and cognition were associated with activities of daily living independence.

A toolbox for the longitudinal assessment of healthspan in aging mice

The number of people aged over 65 is expected to double in the next 30 years. For many, living longer will mean spending more years with the burdens of chronic diseases such as Alzheimer's disease, cardiovascular disease, and diabetes. Although researchers have made rapid progress in developing geroprotective interventions that target mechanisms of aging and delay or prevent the onset of multiple concurrent age-related diseases, a lack of standardized techniques to assess healthspan in preclinical murine studies has resulted in reduced reproducibility and slow progress. To overcome this, major centers in Europe and the United States skilled in healthspan analysis came together to agree on a toolbox of techniques that can be used to consistently assess the healthspan of mice. Here, we describe the agreed toolbox, which contains protocols for echocardiography, novel object recognition, grip strength, rotarod, glucose tolerance test (GTT) and insulin tolerance test (ITT), body composition, and energy expenditure. The protocols can be performed longitudinally in the same mouse over a period of 4-6 weeks to test how candidate geroprotectors affect cardiac, cognitive, neuromuscular, and metabolic health.

Low Protein Intake Irrespective of Source is Associated with Higher Mortality Among Older Community-dwelling Men

OBJECTIVES

Our aim was to determine the association between protein intake (overall and by source) and all-cause and cause-specific mortality among older men.

DESIGN

Prospective cohort study.

SETTING

5790 ambulatory community-dwelling older men from multicenter Osteoporotic Fractures in Men (MrOS) study.

MEASUREMENTS

Total energy and protein intake, and protein intake by source (dairy, non-dairy animal, plant) were assessed using a 69-item food frequency questionnaire. We included up to 10-year follow-up with adjudicated cardiovascular, cancer and other mortality outcomes. We used time-to-event analysis with protein exposures, mortality outcome, and adjusted for possible confounders including age, center, education, race, smoking, alcohol use, physical activity, weight, total energy intake (TEI), and comorbidities. Hazard ratios were expressed per each unit=2.9% TEI decrement for all protein intake variables.

RESULTS

The mean (SD) baseline age of 5790 men was 73.6 (5.8) y. There were 1611 deaths and 211 drop-outs prior to 10 years, and 3868 men who were alive at the 10-year follow-up. The mean (SD) total protein intake was 64.7 (25.8) g/d, while the mean (SD) intake expressed as percent of total energy intake (%TEI) was 16.1 (2.9) %TEI. Lower protein intake was associated with an increased risk of death, with unadjusted HR=1.11 (95% CI: 1.06, 1.17) and adjusted HR=1.09 (95% CI: 1.04, 1.14) and the associations for protein intake by source were similar. The adjusted HR for cancer mortality was HR=1.13 (95% CI: 1.03, 1.25) while the association for CVD mortality was HR=1.08 (95% CI: 0.99, 1.18).

CONCLUSIONS

Low protein intake, irrespective of source, was associated with a modest increase in risk of all-cause and cause-specific mortality among older men. Special consideration should be given to level of protein intake among older adults.

Increased gait variability during robot-assisted walking is accompanied by increased sensorimotor brain activity in healthy people

BACKGROUND

Gait disorders are major symptoms of neurological diseases affecting the quality of life. Interventions that restore walking and allow patients to maintain safe and independent mobility are essential. Robot-assisted gait training (RAGT) proved to be a promising treatment for restoring and improving the ability to walk. Due to heterogenuous study designs and fragmentary knowlegde about the neural correlates associated with RAGT and the relation to motor recovery, guidelines for an individually optimized therapy can hardly be derived. To optimize robotic rehabilitation, it is crucial to understand how robotic assistance affect locomotor control and its underlying brain activity. Thus, this study aimed to investigate the effects of robotic assistance (RA) during treadmill walking (TW) on cortical activity and the relationship between RA-related changes of cortical activity and biomechanical gait characteristics.

METHODS

Twelve healthy, right-handed volunteers (9 females; M = 25 ± 4 years) performed unassisted walking (UAW) and robot-assisted walking (RAW) trials on a treadmill, at 2.8 km/h, in a randomized, within-subject design. Ground reaction forces (GRFs) provided information regarding the individual gait patterns, while brain activity was examined by measuring cerebral hemodynamic changes in brain regions associated with the cortical locomotor network, including the sensorimotor cortex (SMC), premotor cortex (PMC) and supplementary motor area (SMA), using functional near-infrared spectroscopy (fNIRS).

RESULTS

A statistically significant increase in brain activity was observed in the SMC compared with the PMC and SMA (p < 0.05), and a classical double bump in the vertical GRF was observed during both UAW and RAW throughout the stance phase. However, intraindividual gait variability increased significantly with RA and was correlated with increased brain activity in the SMC (p = 0.05; r = 0.57).

CONCLUSIONS

On the one hand, robotic guidance could generate sensory feedback that promotes active participation, leading to increased gait variability and somatosensory brain activity. On the other hand, changes in brain activity and biomechanical gait characteristics may also be due to the sensory feedback of the robot, which disrupts the cortical network of automated walking in healthy individuals. More comprehensive neurophysiological studies both in laboratory and in clinical settings are necessary to investigate the entire brain network associated with RAW.

Exploring reach and experiences of participation in health-promoting senior meetings in a municipality context

Aim

To explore reach and experiences of participants during implementation of health-promoting meetings of seniors in a Swedish municipality context.

Subjects and methods

A mixed-methods approach was used, including older people who were recruited consecutively and invited to participate as they applied for health care and/or home help services in the municipality. Inclusion criterion was allocation of “early” home-care services, e.g., meals on wheels, safety alarms. Health-care services were limited to persons applying for an outside walker. The intervention was multi-professional, e.g., occupational therapy and physiotherapy. Each session included a mix of short lectures and group discussions about, for example, the importance of engagement in meaningful activity, social contacts, and physical activity. Recruitment procedures were modified during the trial in order to enhance reach. The data collection included information on the flow of participants during recruitment and participation in the intervention, field notes covering the experience of implementing the intervention, a survey covering adherence to recruitment procedures, and qualitative interviews exploring the experience of participants.

Results

Senior meetings were experienced as positive and strengthened the participants in dealing with health-related concerns. The identification of potential participants and recruitment were challenging, but as recruitment procedures were modified, a higher proportion of potential participants were reached. In all, there were 29 participants over the study period.

Conclusion

For health-promoting meetings to enable community-dwelling older people to fulfill their potential by positively affecting health outcomes, recruitment procedures for optimizing reach is a critical feature.

Physical Performance Trajectories and Mortality Among Older Mexican Americans

Background

We sought to identify distinct trajectory classes of physical performance in Mexican Americans aged 75 years and older and to examine whether these trajectories predict mortality.

Methods

We used four waves of Hispanic Established Populations for Epidemiologic Studies of the Elderly (H-EPESE) data for adults 75 years and older from 2004-2005 to 2013. Latent growth curve analysis was used to identify distinct trajectory classes. Multinomial logistic regression analysis was used to examine the association between baseline characteristics and the newly constructed trajectories. Cox proportional hazards regression models examined the hazard of mortality as a function of Short Physical Performance Battery (SPPB) trajectories.

Results

The study follow-up period was approximately 9.5 years. One thousand four hundred and eleven adults were successfully classified into three (low-declining, high-declining, and high-stable) physical performance trajectory classes. Depressive symptoms (relative risk ratio = 1.94, 95% confidence interval [CI] = 1.17-3.22), diabetes (relative risk ratio = 2.44, 95% CI = 1.63-3.65), number of other comorbid health conditions (relative risk ratio = 1.40, 95% CI = 1.16-1.68), and obesity (relative risk ratio = 2.83, 95% CI = 1.67-4.80), increased the relative risk of classification into the low, relative to high-stable trajectory class. Male gender and foreign-born status significantly reduced risk of classification in the low-declining and high-declining trajectory classes. We observed a statistically significant association between low-declining (hazard ratio = 3.01, 95% CI = 2.34-3. 87) and high-declining (hazard ratio = 1.64, 95% CI = 1.32-2.03) trajectories and increased risk of mortality.

Conclusions

Differences in mortality across physical performance trajectory classes suggest that these physical performance classes represent differences in underlying disease progression, and thus differences in mortality risk among older Mexican Americans, which warrants additional research to better understand differential physical performance trajectories and their effects on morbidity and mortality in heterogeneous aging populations.

Longitudinal studies of ageing: from insights to impacts: commentary to accompany themed collection on longitudinal studies

'Time is the best diagnostician': who has not thought this? In clinical practice, presentations are often subtle and decisions made in the face of a 'snapshot.' Crystal balls do not exist; yet, insights from longitudinal studies can help to recognise emerging pictures and anticipate typical trajectories. In the multifactorial, biopsychosocial world of geriatrics, the determinants of those trajectories, and hence opportunities to modify them, can be better understood through careful longitudinal disentangling of the wider determinants of health, and this can be done at multiple levels of analysis, from molecules to society. With this collection and commentary, we highlight the approaches, scope and impacts of a selection of longitudinal studies of ageing published in Age and Ageing within the past 10 years. Longitudinal studies can illuminate disease mechanisms, how declines in multiple domains of intrinsic capacity interact, how losses in one domain may influence the path of another, and in turn, how these changes translate to functional disability, or not. Observing trajectories of geriatric syndromes can suggest opportunities for optimisation and prevention in clinical practice and policy. With global opportunities for harmonising data, longitudinal studies are already offering the opportunity for cross-national comparisons and for developing hypotheses about the relative contributions of time, place and society in the trajectories of frailty, disability and quality of life. We also include studies which show how research-based longitudinal data can be synthesised or be linked to administrative datasets. We hope you find this collection as interesting and encouraging as we have.

Process of Decline in Activities of Daily Living of Older Chinese People Prior to Death: Evidence From Three Cohorts

Objective:

The study analyzes the decline in activities of daily living (ADL) prior to death among three cohorts of older Chinese.

Method:

With data from the Chinese Longitudinal Healthy Longevity Survey, the process of decline in ADL in older people born during the periods 1899–1908, 1909–1918, and 1919–1928 is analyzed using the hierarchical linear model with mixed effects.

Results:

The remaining survival time has a stronger effect on changes in ADL than chronological age, and there is significant heterogeneity among the older adults in ADL.

Conclusion:

Decline in ADL is delayed by extending life span. Older people with healthy behaviors, good living conditions in childhood, and age-friendly living environment have long-lasting good ADL during their remaining life span; socioeconomic resources help the older adults with ADL disabilities to survive. Selective effects of mortality and protective effects of socioeconomic resources explain the heterogeneity in ADL and its changes over time.

Higher albumin:creatinine ratio and lower estimated glomerular filtration rate are potential risk factors for decline of physical performance in the elderly: the Cardiovascular Health Study

Introduction

Mildly reduced renal function and elevated urine protein levels are each prospectively associated with hip fracture risk in older adults. Here we determine whether these markers are associated with reduced appendicular muscle performance.

Methods

We prospectively examined the associations of urine albumin:creatinine ratio (ACR) and reduced estimated glomerular filtration rate (eGFR) with longitudinal changes in grip strength and gait speed >2 years in 2317 older community-dwelling men and women (median age 77 years). The median ACR was 9.8 [interquartile range (IQR) 5.40–21.50] mg/g creatinine and the median eGFR was 71.6 (IQR 59.1–83.56) mL/min/1.73 m². Models were adjusted for demographic factors, clinical history and biochemical measures in four candidate pathways: diabetes, oxidative stress, inflammation and fibrosis.

Results

In demographic- and covariate-adjusted models, a 2-fold higher baseline urine ACR was associated with longitudinal changes of −0.17 kg [95% confidence interval (CI) −0.29 to −0.06) in grip strength and −1.10 cm/s (95% CI −1.67 to −0.53) gait speed per year. Corresponding estimates for a 10 mL/min/1.73 m² lower baseline eGFR were −0.13 kg (95% CI −0.23 to −0.04) and −0.89 cm/s (95% CI −1.37 to −0.40), respectively. The associations of a 2-fold higher baseline ACR and a 10 mL/min/1.73 m² lower baseline eGFR using cystatin C with grip strength and gait speed were equivalent to ∼1.2–1.9 additional years of age. Adjustment for covariates in candidate pathways did not attenuate these estimates.

Conclusions

In older adults, higher ACR and lower eGFR are potential risk factors for a decline of physical performance >2 years.

Explaining the unique nature of individual gait patterns with deep learning

Machine learning (ML) techniques such as (deep) artificial neural networks (DNN) are solving very successfully a plethora of tasks and provide new predictive models for complex physical, chemical, biological and social systems. However, in most cases this comes with the disadvantage of acting as a black box, rarely providing information about what made them arrive at a particular prediction. This black box aspect of ML techniques can be problematic especially in medical diagnoses, so far hampering a clinical acceptance. The present paper studies the uniqueness of individual gait patterns in clinical biomechanics using DNNs. By attributing portions of the model predictions back to the input variables (ground reaction forces and full-body joint angles), the Layer-Wise Relevance Propagation (LRP) technique reliably demonstrates which variables at what time windows of the gait cycle are most relevant for the characterisation of gait patterns from a certain individual. By measuring the time-resolved contribution of each input variable to the prediction of ML techniques such as DNNs, our method describes the first general framework that enables to understand and interpret non-linear ML methods in (biomechanical) gait analysis and thereby supplies a powerful tool for analysis, diagnosis and treatment of human gait.

Defining Vitality: Associations of Three Operational Definitions of Vitality with Disability in Instrumental Activities of Daily Living and Frailty among Elderly Over a 3-Year Follow-Up (MAPT Study)

OBJECTIVES

This study aimed to examine the associations of three operational definitions of vitality with variation in instrumental activities of daily living (IADL) and frailty over a 3-year follow-up among non-demented, community-dwelling elderly.

DESIGN

Observational study.

SETTING AND PARTICIPANTS

1,679 elderly >70y (64.7% female) participants of the Multidomain Alzheimer Preventive Trial (MAPT).

MEASUREMENTS

Vitality was defined as a psychological concept using three items from the Geriatric Depression Scale; as a physical construct using the highest quartile for hand grip strength; and as global physiological reservoir using a combination of good physical and cognitive functions. Variables were assessed at baseline, 6, 12, 24 and 36 months of follow-up.

RESULTS

Prevalence of high vitality at baseline was 57.1%, 28.5% and 21.6% for psychological, physical, and physiological reservoir, respectively. People with high vitality presented higher IADL scores compared to people with low vitality for all definitions. Analysis from the mixed-effect model found no differences between vitality groups for IADL performance across all definitions. IADL scores improved among subjects with high vitality over time, independent on the definition; while no significant variation was observed among those with low vitality. Participants with low vitality presented 2.0 to 6.1 higher odds of having more frailty components over time (p<0.0001).

CONCLUSION

High vitality defined as a concept related to psychological, physical, or physiological reservoir constructs were positively associated with better IADL performance and with reduced likelihood of frailty worsening over time.

Mortality Following Trajectories of Mobility Limitations: The Modifying Impact of Social Factors

Objective: How are trajectories of mobility limitations (MLs) among older adults associated with mortality? Do social factors modify these associations? Method: Group-based trajectory modeling was used to identify four trajectories of MLs over a period of 4.5 years among 3,055 older Danes. Mortality analyses were conducted using additive hazard regression models. Results: Compared to older adults without MLs, older adults with high level of MLs who experienced further increase in MLs were associated with the most additional deaths followed by older adults with no MLs at baseline who later experienced limitations and older adults with a medium ML level at baseline who later experienced further increase in limitations. Men and 80-year olds experienced more additional deaths following adverse ML trajectories than women and 75-year olds. Discussion: Trajectories that led to higher ML levels were associated with most additional deaths especially among men and in the oldest age group.

Women's spousal choices and a man's handshake: Evidence from a Norwegian study of cohort differences

Both high grip strength and being married independently relate to better functional capacity and health at older ages, but the combined effect of marital status and strength have not been investigated. Especially at older ages, declining strength can have adverse health and social consequences, where having a spouse could potentially help with everyday support and alleviate some of the negative effects of sarcopenia. We investigate how grip strength relates to being married among two cohorts of 59–71 year olds (born 1923-35 and 1936-48) in the Norwegian city of Tromsø, controlling for a broad set of health variables and sociodemographic characteristics. The baseline included N = 5009 participants of whom 649 died during follow-up. We find that for men, particularly among younger cohorts, the physically stronger are more likely to be married, but no relation is found for women. This is consistent with a hypothesis that women increasingly have selected male marital partners based on preferred individual traits, whereas men do not emphasize strength when selecting women. We find that both marital status and grip strength independently affect mortality, but there is no significant joint effect. However, the distribution of strength and marital status implies that more men than women and increasing shares of later born cohorts have a “double-burden” of low strength and a lack of support from a spouse.

Associations of Grip Strength and Change in Grip Strength With All-Cause and Cardiovascular Mortality in a European Older Population

Objective:

(1) To examine the associations between 3 measures of grip strength: static grip strength, change in grip strength, and the combination of grip strength and its change, with all-cause and cardiovascular mortality, and (2) to determine which measure is the most powerful predictor of all-cause and cardiovascular mortality among the European older population.

Method:

Data come from the first 4 waves of the Survey of Health, Ageing and Retirement in Europe (SHARE). A Cox proportional hazard model and a competing risk regression model were used to assess the associations. To determine the best predictor, Akaike information criterion was applied.

Results:

Grip strength and the combination of grip strength and its change were associated with all-cause and cardiovascular mortality. Change in grip strength was correlated with only all-cause mortality. Among the 3 measures, the static measure of grip strength was the best predictor of cardiovascular mortality whereas the combined measure is that of all-cause mortality.

Discussion:

Grip strength is a significant indicator of all-cause and cardiovascular mortality. The combination of grip strength and its change can be used to increase the accuracy for prediction of all-cause mortality among older persons.

Role of Dietary Protein and Muscular Fitness on Longevity and Aging

Muscle atrophy is an unfortunate effect of aging and many diseases and can compromise physical function and impair vital metabolic processes. Low levels of muscular fitness together with insufficient dietary intake are major risk factors for illness and mortality from all causes. Ultimately, muscle wasting contributes significantly to weakness, disability, increased hospitalization, immobility, and loss of independence. However, the extent of muscle wasting differs greatly between individuals due to differences in the aging process per se as well as physical activity levels. Interventions for sarcopenia include exercise and nutrition because both have a positive impact on protein anabolism but also enhance other aspects that contribute to well-being in sarcopenic older adults, such as physical function, quality of life, and anti-inflammatory state. The process of aging is accompanied by chronic immune activation, and sarcopenia may represent a consequence of a counter-regulatory strategy of the immune system. Thereby, the kynurenine pathway is induced, and elevation in the ratio of kynurenine to tryptophan concentrations, which estimates the tryptophan breakdown rate, is often linked with inflammatory conditions and neuropsychiatric symptoms. A combined exercise program consisting of both resistance-type and endurance-type exercise may best help to ameliorate the loss of skeletal muscle mass and function, to prevent muscle aging comorbidities, and to improve physical performance and quality of life. In addition, the use of dietary protein supplementation can further augment protein anabolism but can also contribute to a more active lifestyle, thereby supporting well-being and active aging in the older population.

Dodds R, Kirkwood TBL, Sayer AA. Initial level and rate of change in grip strength predict all-cause mortality in very old adults

Objective

to investigate the associations between initial level and rate of change in grip strength (GS) and all-cause mortality in very old adults (≥85 years) over a 9.6-year follow-up.

Methods

prospective mortality data from 845 participants in the Newcastle 85+ Study were analysed for survival in relation to GS (kg, baseline and 5-year mean change) using Cox proportional hazards models.

Results

during the follow-up, 636 (75.3%) participants died. Higher baseline GS was associated with a decreased risk of mortality in all participants [hazard ratio (HR) = 0.95, 95% confidence interval (CI): 0.93-0.98, P < 0.001], men (HR = 0.97, 95% CI: 0.95-0.99, P = 0.009) and women (HR = 0.96, 95% CI: 0.94-0.99, P = 0.007) after adjustment for health, lifestyle and anthropometric factors. Overall GS slope had a downward trajectory and was determined in 602 participants: 451 experienced constant decline (negative slope) and 151 had increasing GS (positive slope) over time. Men and women with a negative slope had a 16 and 33% increased risk of mortality, respectively, with every kg/year decline in GS (P ≤ 0.005), and participants with a positive slope had a 31% decreased risk of mortality (P = 0.03) irrespective of baseline GS and key covariates.

Conclusion

higher baseline GS and 5-year increase in GS were protective of mortality, whilst GS decline was associated with an increased risk of mortality in the very old over 9.6 years, especially in women. These results add to the biological and clinical importance of GS as a powerful predictor of long-term survival in late life.

Rhythmic Interlimb Coordination Impairments and the Risk for Developing Mobility Limitations

BACKGROUND

The identification of novel rehabilitative impairments that are risk factors for mobility limitations may improve their prevention and treatment among older adults. We tested the hypothesis that impaired rhythmic interlimb ankle and shoulder coordination are risk factors for subsequent mobility limitations among older adults.

METHODS

We conducted a 1-year prospective cohort study of community-dwelling older adults (N = 99) aged 67 years and older who did not have mobility limitations (Short Physical Performance Battery score > 9) at baseline. Participants performed antiphase coordination of the right and left ankles or shoulders while paced by an auditory metronome. Using multivariable logistic regression, we determined odds ratios (ORs) for mobility limitations at 1-year follow-up as a function of coordination variability and asymmetry.

RESULTS

After adjusting for age, sex, body mass index, Mini-Mental State Examination score, number of chronic conditions, and baseline Short Physical Performance Battery score, ORs were significant for developing mobility limitations based on a 1 SD difference in the variability of ankle (OR = 1.88; 95% confidence interval [CI]: 1.16-3.05) and shoulder (OR = 1.96; 95% CI: 1.17-3.29) coordination. ORs were significant for asymmetry of shoulder (OR = 2.11; 95% CI: 1.25-3.57), but not ankle (OR = 0.95; 95% CI: 0.59-1.55) coordination. Similar results were found in unadjusted analyses.

CONCLUSIONS

The results support our hypothesis that impaired interlimb ankle and shoulder coordination are risk factors for the development of mobility limitations. Future work is needed to further examine the peripheral and central mechanisms underlying this relationship and to test whether enhancing coordination alters mobility limitations.

Motor functioning differentially predicts mortality in men and women

INTRODUCTION

Research indicates gender differences in functional performance at advanced ages, but little is known about their impact on longevity for men and women.

OBJECTIVE

To derive a set of motor function factors from a battery of functional performance measures and examine their associations with mortality, incorporating possible gender interactions.

METHOD

Analyses were performed on the longitudinal Swedish Adoption/Twin Study of Aging (SATSA) including twenty-four assessments of motor function up to six times over a 19-year period. Three motor factors were derived from several factor analyses; fine motor, balance/upper strength, and flexibility. A latent growth curve model was used to capture longitudinal age changes in the motor factors and generated estimates of intercept at age 70 (I), rates of change before (S1) and after age 70 (S2) for each factor. Cox regression models were used to determine how gender in interaction with the motor factors was related to mortality.

RESULTS

Females demonstrated lower functional performance in all motor functions relative to men. Cox regression survival analyses demonstrated that both balance/upper strength, and fine motor function were significantly related to mortality. Gender specific analyses revealed that this was true for women only. For men, none of the motor factors were related to mortality.

CONCLUSION

Women demonstrated more difficulties in all functioning facets, and only among women were motor functioning (balance/upper strength and fine motor function) associated with mortality. These results provide evidence for the importance of considering motor functioning, and foremost observed gender differences when planning for individualized treatment and rehabilitation.

Self-motivated and stress-response performance assays in mice are age-dependent

Chronic health conditions of the elderly lead to limitations in physical activity with disability, anxiety, and increased need for medical care and assisted living conditions. Physical performance tests are used to screen for pending loss of mobility and can serve as endpoints to monitor the effectiveness of intervention measures. Since limited mobility is associated with the physical and mental health of a person, evaluation of this in preclinical aging studies in mice will provide a translational approach for testing new intervention strategies. We assessed physiological parameters in 4, 12, 20 and 28month old C57BL/6 and CB6F1 male mice using a rotating rod, a free running wheel, and a photo beam activity field, designed to determine changes in coordinated walking ability, self-motivated running distance, and anxiety response to a novel environment, respectively. Older mice showed decreased coordinated walking times and decreased running distances, predictive of physical performance ability and motivation in the elderly. Changes in both lateral and vertical movements were observed in a novel cage environment suggesting different levels of anxiety. Because the genetic background of the two mouse strains influenced test results in an age-dependent manner, it is imperative to recognize that diverse genetic backgrounds in mice may yield different data in preclinical studies and would need to be interpreted individually for translational applications.

Mortality in the Hertfordshire Ageing Study: association with level and loss of hand grip strength in later life

Background

weak hand grip strength in later life is a risk factor for disability, morbidity and mortality and is central to definitions of sarcopenia and frailty. It is unclear whether rate of change in grip strength adds to level of grip strength as a risk factor for poor ageing outcomes.

Methods

study participants were 292 community-dwelling men and women whose grip strength was measured during the 1994/5 (average age 67) and 2003/5 (average age 76) phases of the Hertfordshire Ageing Study, UK. Individual rate of change in grip strength was estimated using a residual change method. Mortality was followed-up to 2011 (42 men and 21 women died).

Results

average grip strengths in 2003/5 were 38.4 kg (standard deviation [SD] = 8.1) and 23.7 kg (SD = 6.6) for men and women respectively. Average annualised rates of change in grip strength (2003/5 minus 1994/5) were modest owing to a healthy-participant effect (men: -0.12 kg/y, SD = 0.71; women: 0.08 kg/y, SD = 0.54) but varied widely. Mortality risk varied according to level and rate of change in grip strength (P = 0.03); death rates per 100 person years of follow-up were 6.7 (95% CI: 4.6, 9.6) among participants who lost grip over time and had low grip in 2003/5, in contrast with 0.8 (95% CI: 0.1, 5.8) among participants whose grip changed little over time and remained high in 2003/5.

Conclusions

levels of grip strength in later life should be considered in conjunction with estimates of change in grip strength identified by repeat measurement over time. Normative data for longitudinal change in grip strength are required.

Role of physical activity in mortality prediction in elderly hospice patients

The prediction of life-expectancy in terminally ill patients is important both for medical and social reasons but it is widely recognized as being inaccurate. The aim of this study was to investigate the mortality predictors and indicators of life extension among elderly patients in a hospice service center. In order to determine the mortality predictors, we investigated the relationship between patients’ cognitive status using the Korean-Mini Mental State Examination & Global Deterioration Scale (K-MMSE & GDS), the patient’s physical function using the instrumental Activities of Daily Living (ADL) score, and the patient’s blood component values. The subjects included 43 men and 57 women with a mean age of 82.4±8.4 years, and a mean nursing period of 11.1±12.2 months. These terminally ill patients were enrolled in a cross-sectional study. All data were collected from paper and electronic charts, and patient interviews. A simple correlation analysis was performed to determine the relationship between the variables and to satisfy the normal distribution (P<0.01). The results revealed that the time of death negatively correlated with ADL score (r=−0.273, P=0.006). However, the K-MMSE & GDS, and the values of blood component such as albumin, gamma-glutamic transpeptidase, blood urea nitrogen, and creatinine were not correlated with the time of death. Consequently, the ADL score might be an important predictor of mortality and life extension in elderly patients. Therefore, in order to improve ADL score, physical exercise and overall fitness may be potential non-pharmacologic methods useful in preventing mortality in elderly people.

Increased Physical Activity and Fitness above the 50(th) Percentile Avoid the Threat of Older Adults Becoming Institutionalized: A Cross-sectional Pilot Study

The objective of this study was to analyze the impact of physical fitness and physical activity on the threat of older adults without cognitive impairment becoming institutionalized. This cross-sectional study involved 195 non-institutionalized (80.1 ± 4.4 years) and 186 institutionalized (83.8 ± 5.2years) participants. Cognitive impairment was assessed using Mini-Mental State Examination, measures of physical fitness were determined by the Senior Fitness Test, and physical activity was assessed using the International Physical Activity Questionnaire. Multivariate binary logistic analysis selected four main determinants of institutionalization in both genders: The likelihood of becoming institutionalized increased by +18.6% for each additional year of age, whereas it decreased by -24.8% by each fewer kg/m(2) in body mass index (BMI), by -0.9% for each additional meter performed in the aerobic endurance test, and by -2.0% for each additional 100 metabolic equivalent of task (MET)-min/week of physical activity expenditure (p < 0.05). Values ≤50(th) percentile (age ≥81 years, BMI ≥26.7 kg/m(2), aerobic endurance ≤367.6 meters, and physical activity ≤693 MET-min/week) were computed using receiver operating characteristics analysis as cutoffs discriminating institutionalized from non-institutionalized older adults. The performance of physical activity, allied to an improvement in physical fitness (mainly BMI and aerobic endurance), may avoid the threat of institutionalization of older adults without cognitive impairment only if they are above the 50(th) percentile. The following parameters are highly recommended: Expending ≥693 MET-min/week on physical activity, having a BMI ≤26.7 kg/m(2), and being able to walk ≥367.6 meters in the aerobic endurance test, especially above the age of 80 years. The discovery of this trigger justifies the development of physical activity programs targeting the pointed cutoffs in old and very old adults.

Three year functional changes and long-term mortality hazard in community-dwelling older men

BACKGROUND

Low levels of physical function have been associated with higher mortality hazard in older persons. However, few studies have investigated the association between functional changes and subsequent mortality. This study aimed to examine whether 3-year functional changes independently predict subsequent all-cause mortality.

METHODS

This population-based cohort study included 171 community-dwelling men aged ≥71years at wave 2 (baseline of the present analysis), living in the semi-rural community of Merelbeke (Belgium). Physical function assessments included the Short Form-36 (SF-36) Physical Function Index, Grip strength, Chair rising, and Timed Up and Go. Changes over a 3-year time were calculated using data obtained at four annual visits.

RESULTS

After a 15-year follow-up, 149 men (87%) died. Median survival time was 8.2 (4.2-12.4) years. Physical function assessed at a single time point (at wave 2 or wave 5) was significantly associated with subsequent mortality hazard, independently from future or preceding 3-year changes. Greater functional declines during the 3-year follow-up were associated with higher mortality hazards. These associations were 1) more pronounced within the first seven years, 2) independent from baseline age, polypharmacy, depression, disability, and physical function, and 3) no longer significant when closure physical function was taken into account.

CONCLUSION

Physical function assessed at a single time point is a robust predictor of all-cause long-term mortality in community-dwelling older men. Yet, repeated assessments of physical function can provide prognostic information beyond that available from single initial assessment. However, with repeated assessments, most prognostic information can be found in the final assessment of physical function.

Grip strength is potentially an early indicator of age-related decline in mice

The hand grip test has been correlated with mobility and physical performance in older people and has been shown to be a long-term predictor of mortality. Implementation of new strategies for enhancing healthy aging and maintaining independent living are dependent on predictable preclinical studies. The mouse is used extensively as a model in these types of studies, and the paw grip strength test is similar to the hand grip test for people in that it assesses the ability to grip a device with the paw, is non-invasive and easy to perform, and provides reproducible information. However, little has been reported on how grip strength declines with increasing age in mice. This report shows that grip strength was decreased in C57BL/6 (B6) NIA and C57BL/6×BALB/c F1 (CB6F1) NIA male mice at 12 months of age compared to 8-month-old mice, and continued a robust decline to 20 months and then 28 months of age, when the study was terminated. The decline was not related to lean muscle mass, but extensive age-related carpal and digital exostosis could help explain the decreased grip strength times with increasing age. In conclusion, the grip strength test could be useful in mouse preclinical studies to help make translational predictions on treatment strategies to enhance healthy aging.

Purpose in Life is Associated with a Reduced Risk of Incident Physical Disability in Aging U.S. Military Veterans

OBJECTIVES

The current study evaluated the incidence and determinants of physical disability in a contemporary, nationally representative sample of U.S. military veterans.

DESIGN, SETTING, PARTICIPANTS

Data were analyzed from the National Health and Resilience in Veterans Study, a nationally representative, prospective cohort study of 1,686 veterans aged 55 years and older. Waves 1 and 2 were conducted in 2011 and 2013, respectively.

MEASUREMENTS

Potential determinants of incident disability in activities of daily living (ADL; e.g., bathing, dressing) and instrumental activities of daily living (IADL; e.g., food preparation, medication adherence) were assessed at Wave 1, and included sociodemographic characteristics, and risk (e.g., medical conditions, psychiatric distress), and protective psychosocial (e.g., psychological resilience, purpose in life) factors.

RESULTS

The two-year incidence of any physical disability (ADL or IADL) among veterans aged 55 years and older was 11.5%, and the incidence of ADL and IADL disability was 3.0% and 11.4%, respectively. Older age, being married/cohabiting, and number of medical conditions-specifically, diabetes, heart attack, and chronic pain-were associated with an increased risk of any incident physical disability and incident IADL disability (adjusted odds ratio [AOR] range: 1.10-3.10). Retirement was associated with an increased risk of incident ADL disability (AOR: 7.53, 95% CI: 1.37-41.51). Purpose in life was found to be protective for incident IADL disability (AOR: 0.93, 95% CI: 0.87-0.99).

CONCLUSIONS

Although greater medical burden is associated with increased incidence of physical disability in U.S. veterans, results of this study suggest that initiatives designed to foster greater purpose in life may help protect against the development of physical disability in this rapidly growing segment of the population.

Association between phthalate exposure and lower handgrip strength in an elderly population: a repeated-measures study

BACKGROUND

Decreased muscle strength can lead to adverse health outcomes in the elderly. A potential association between phthalate exposure and muscle strength was suggested previously, but has not been investigated directly. We hypothesized that phthalate exposure is associated with lower handgrip strength and that the association is modified by the dietary omega-6 to omega-3 ratio.

METHODS

We analyzed 1,228 participants (≥60 years of age) recruited in Seoul and Asan, Republic of Korea. The study participants were surveyed up to three times between 2012 and 2015. At every survey, we collected urine samples and measured handgrip strength twice for each hand. The associations between urine phthalate metabolite concentrations and handgrip strength were evaluated using linear mixed models. Based on dietary information from 391 individuals who participated in the first survey in Seoul, we evaluated the heterogeneity of the association for those with high and low omega-6 to omega-3 ratios, using 8.81 (the 75th quantile) as a cutoff value.

RESULTS

Log-transformed creatinine-adjusted concentrations of mono-(2-ethyl-5-oxohexyl phthalate (MEOHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono-n-butyl phthalate (MnBP) were inversely associated with all measured handgrip strengths (β = -0.69 to -0.42, all p-values < 0.05). Associations between phthalate biomarkers and handgrip strength did not differ by sex. When the dietary subgroup was stratified by the omega-6 to omega-3 ratio, the associations were stronger among participants with high ratios.

CONCLUSIONS

We found inverse associations between phthalate biomarkers and handgrip strength in the elderly; this association was modified by the dietary omega-6 to omega-3 ratio.

Functional Independence in Late-Life: Maintaining Physical Functioning in Older Adulthood Predicts Daily Life Function after Age 80

BACKGROUND

We examined physical functioning (PF) trajectories (maintaining, slowly declining, and rapidly declining) spanning 15 years in older women aged 65-80 and protective factors that predicted better current levels and less decline in functional independence outcomes after age 80.

METHODS

Women's Health Initiative extension participants who met criteria (enrolled in either the clinical trial or observational study cohort, >80 years at the data release cutoff, PF survey data from initial enrollment to age 80, and functional independence survey data after age 80) were included in these analyses (mean [SD] age = 84.0 [1.4] years; N = 10,478). PF was measured with the SF-36 (mean = 4.9 occasions). Functional independence was measured by self-reported level of dependence in basic and instrumental activities of daily living (ADLs and IADLs) (mean = 3.4 and 3.3 occasions).

RESULTS

Maintaining consistent PF in older adulthood extends functional independence in ADL and IADL in late-life. Protective factors shared by ADL and IADL include maintaining PF over time, self-reported excellent or very good health, no history of hip fracture after age 55, and no history of cardiovascular disease. Better IADL function is uniquely predicted by a body mass index less than 25 and no depression. Less ADL and IADL decline is predicted by better self-reported health, and less IADL decline is uniquely predicted by having no history of hip fracture after age 55.

CONCLUSIONS

Maintaining or improving PF and preventing injury and disease in older adulthood (ages 65-80) has far-reaching implications for improving late-life (after age 80) functional independence.

Role of physical activity, physical fitness, and chronic health conditions on the physical independence of community-dwelling older adults over a 5-year period

The variability in the individual characteristics and habits could help determine how older adults maintain independence. The impact of the variability in physical activity, physical fitness, body composition, and chronic health conditions (co-morbidities) on the independence of older adults, especially over time, is seldom examined. This study aims to analyze quantitatively the impact of baseline values and changes in physical activity, physical fitness, body composition, and co-morbidities on the physical independence of community-dwelling, older adults over a 5-year period. Data from 106 and 85 community-dwelling adults (≥60 years) were collected at baseline and after five years, respectively. Linear regression selected the main predictors of changes in physical independence as follows: the baseline physical independence (β=0.032, R(2)=9.9%) and co-morbidities (β=-0.191, R(2)=6.3%) and the changes in co-morbidities (β=-0.244, R(2)=10.8%), agility (β=-0.288, R(2)=6.7%), aerobic endurance (β=0.007, R(2)=3.2%), and walking expenditure (β=0.001, R(2)=5.1%) (p<0.05). In conclusion, baseline physical independence, baseline co-morbidities, and changes in co-morbidities, walking, agility, and aerobic endurance predicted physical independence over five years regardless of age and gender. Gains of up to 8.3% in physical independence were associated with improvements in these variables, which corresponds to regaining independence for performing one or two activities of daily living.

Motor Function Is Associated With Incident Disability in Older African Americans

BACKGROUND

Disability in older African American adults is common, but its basis is unclear. We tested the hypothesis that the level of motor function is associated with incident disability in older African Americans after adjusting for cognition.

METHODS

A prospective observational cohort study of 605 older community-dwelling African American adults without dementia was carried out. Baseline global motor score summarized 11 motor performances, cognition was based on 19 cognitive tests, and self-reported disability was obtained annually. We examined the association of motor function with incident disability (instrumental activities of daily living [IADL], activities of daily living [ADL], and mobility disability) with a series of Cox proportional hazards models which controlled for age, sex, and education.

RESULTS

Average follow-up was about 5 years. In proportional hazards models, a 1-SD increase in baseline level of global motor score was associated with about a 50% decrease in the risk of subsequent IADL, ADL, and mobility disability (all p values < .001). These associations were unchanged in analyses controlling for cognition and other covariates. Further, the association of global motor score and incident ADL disability varied with the level of cognition (estimate -5.541, SE 1.634, p < .001), such that higher motor function was more protective at higher levels of cognition. Mobility and dexterity components of global motor score were more strongly associated with incident disability than strength (all p values < .001).

CONCLUSIONS

Better motor function in older African Americans is associated with a decreased risk of developing disability. Moreover, the association of motor function and disability is stronger in individuals with better cognitive function.

Leisure Engagement: Medical Conditions, Mobility Difficulties, and Activity Limitations-A Later Life Perspective

Objectives. This study aims to investigate the impact of medical conditions, mobility difficulties, and activity limitations on older people's engagement in leisure activities. Methods. The analyses are based on a cross regional survey carried out in 2010 in the Bothnia region (Northern Sweden and Western Finland). A posted questionnaire, which included questions on different aspects of leisure engagement, medical history, and health, was sent out to older persons in the region. The final sample consisted of 5435 persons aged 65, 70, 75, and 80 years. The data was analyzed by using ordinary least squares (OLS) multivariate regression. Results. The most important predictor of leisure engagement abstention among older people is the prevalence of activity limitations, whereas mobility difficulties and medical conditions play less important roles. The strong negative association between activity limitations and leisure engagement remains significant even after we control for individual, sociodemographic characteristics, and country. Discussion. This study provides a window into leisure engagement in later life and factors influencing the magnitude of engagement in leisure activities.