Common chronic diseases and general impairments as determinants of walking disability in the oldest-old population

Development of a virtual reality-based intervention for community walking post stroke: an integrated knowledge translation approach

PURPOSE

To develop a virtual reality (VR) based intervention targeting community walking requirements.

METHODS

Two focus groups each involving 7 clinicians allowed exploring optimal features, needed support and perceived favorable/unfavorable factors associated with the use of the VR-based intervention from the clinicians' perspective. Three stroke survivors and 2 clinicians further interacted with the intervention and filled questionnaires related to acceptability and favorable/unfavorable perceptions on the VR intervention. Stroke participants additionally rated their perceived effort (NASA Tax Load Index), presence (Slater-Usoh-Steed) and cybersickness (Simulator Sickness Questionnaire).

RESULTS

Results identified optimal features (patient eligibility criteria, task complexity), needed support (training, human assistance), as well as favorable (cognitive stimulation, engagement, representativeness of therapeutic goals) and unfavorable factors (misalignment with a natural walking pattern, client suitability, generalization to real-life) associated with the intervention. Acceptability scores following the interaction with the tool were 28 and 42 (max 56) for clinicians and ranged from 43 to 52 for stroke participants. Stroke participants reported moderate perceptions of effort (range:20-33/max:60), high levels of presence (29-42/42) and minimal cybersickness (0-3/64).

CONCLUSION

Findings collected in the early development phase of the VR intervention will allow addressing favorable/unfavorable factors and incorporating desired optimal features, prior to conducting effectiveness and implementation studies.

The effects of the COVID-19 pandemic on the psychosocial well-being of people with disabilities

Background

Before the COVID-19 pandemic, people with mobility, vision, hearing, and cognitive disabilities were at a higher risk of lower psychosocial well-being than people without disabilities. It is, therefore, of great importance to investigate whether the pandemic has exacerbated this difference.

Objective

This study examines whether people with disabilities (categorized as mobility, vision, hearing, cognitive, and any disabilities) report more COVID-19-related negative effects on psychosocial well-being (loneliness, decreased social contact, decreased hope for the future, concerns about being infected) than people without disabilities.

Methods

We analyzed population-based data from the Finnish Health, Welfare, and Services (FinSote) survey carried out in 2020–2021 (N = 22 165, age 20+). Logistic regression models were applied, controlling for the effects of age, sex, partnership, living alone, and education.

Results

All disability groups, except those with vision disabilities, reported significantly more often that the pandemic increased loneliness than people without disabilities. There were no significant differences between the disability groups and people without disabilities in decreased social contacts. People with only mobility and cognitive disabilities reported significantly more often that the pandemic decreased their hope for the future than those without disabilities. All disability groups were more often concerned about being infected than people without disabilities, but this effect was not significant among people 75 or older.

Conclusion

The psychosocial well-being of people with specific types of disabilities should receive special attention during crises like the COVID-19 pandemic.

Six-minute walk test in cardiac rehabilitation

Six-minute walk test (6MWT) is a simple and safe tool for assessing exercise tolerance in  various  categories  of  patients.  Currently,  6MWT  is  used to assess the functional status of a patient and determine the strategy of increasing physical activity, primarily in patients with reduced exercise tolerance and contraindications for cardiopulmonary exercise  test. The basic requirements for the 6MWT are presented, taking into account the factors affecting its  informativeness  and  accuracy,  as  well  as the interpretation of results. The diagnostic and prognostic value of 6MWT in different categories of patients are discussed. The prospects for 6MWT use in cardiac rehabilitation for planning rehabilitation program, prescribing exercises,  determining  the  risk   of   complications,   and   evaluating the effectiveness  are  considered.  The  limitations  of  6MWT  and  ways to overcome it, as well as directions for further research are presented.

Do senescence markers correlate in vitro and in situ within individual human donors?

Little is known on how well senescence markers in vitro and in situ correlate within individual donors. We studied correlations between the same and different in vitro markers. Furthermore, we tested correlations between in vitro markers with in situ p16INK4a positivity.

From 100 donors (20-91 years), cultured dermal fibroblasts were assessed for reactive oxygen species (ROS), telomere-associated foci (TAF), p16INK4a and senescence-associated β-gal (SAβ-gal), with/ without 0.6 µM rotenone for 3 days (short-term). In fibroblasts from 40 donors, telomere shortening, ROS and SAβ-gal were additionally assessed, with/ without 20 nM rotenone for 7 weeks (long-term). In skin from 52 donors, the number of p16INK4a positive dermal cells was assessed in situ.

More than half of the correlations of the same senescence markers in vitro between duplicate experiments and between short-term versus long-term experiments were significant. Half of the different senescence marker correlations were significant within the short-term and within the long-term experiments. The different senescence markers in vitro were not significantly correlated intra-individually with in situ p16INK4a positivity.
In conclusion, the same and different senescence markers are frequently correlated significantly within and between in vitro experiments, but in vitro senescence markers are not correlated with p16INK4a positivity in situ.

When You Can't Walk a Mile: Walking Limitation Prevalence and Associations Among Middle-Aged and Older US Adults with Arthritis: A Cross-Sectional, Population-Based Study

OBJECTIVE

We examined walking limitations and associated characteristics among middle-aged and older US adults with arthritis, overall, and by sex.

METHODS

Using 2005-2006 Arthritis Conditions and Health Effects Survey (ACHES) data (n = 1793), we estimated "a lot" and "any" ("a lot" or "a little" combined) walking limitation for more than 1 mile (1.6 km) among US adults 45 years or older with arthritis and examined associations (sociodemographics, arthritis symptoms and effects, psychosocial measures, and physical health) with walking limitations in unadjusted and multivariable (MV) adjusted logistic regression models using prevalence ratios (PRs) and 95% confidence intervals, accounting for the complex survey design.

RESULTS

Respondents frequently reported "a lot" (48%) and "any" (72%) limitation for more than 1 mile. Women reported higher prevalence of all levels of walking limitation versus men (eg, 51% vs 42% for "a lot" overall); additionally, the gap for walking limitations between women and men widened with age. Limitation was high for both sexes at all ages, affecting 1-in-3 to 4-in-5, depending on level of walking limitation. The strongest MV associations for "a lot" of walking limitation among all respondents included substantial and modest arthritis-attributable life interference (PR = 2.5 and 1.6, respectively), age 75 years or older (PR = 1.5), and physical inactivity and fair/poor self-rated health (PR = 1.4 for both).

CONCLUSION

Walking limitations among middle-aged and older adults are substantial. Existing proven interventions that improve walking ability and physical function may help this population to reduce and delay disability.

A Context-Aware Accurate Wellness Determination (CAAWD) Model for Elderly People Using Lazy Associative Classification

Wireless Sensor Network (WSN) based smart homes are proving to be an ideal candidate to provide better healthcare facilities to elderly people in their living areas. Several currently proposed techniques have implementation and usage complexities (such as wearable devices and the charging of these devices) which make these proposed techniques less acceptable for elderly people, while the behavioral analysis based on visual techniques lacks privacy. In this paper, a context-aware accurate wellness determination (CAAWD) model for elderly people is presented, where behavior monitoring information is extracted by using simple sensor nodes attached to household objects and appliances for the analysis of daily, frequent behavior patterns of elderly people in a simple and non-obtrusive manner. A contextual data extraction algorithm (CDEA) is proposed for the generation of contextually comprehensive behavior-training instances for accurate wellness classification. The CDEA presents an activity’s spatial–temporal information along with behavioral contextual correlation aspects (such as the object/appliance of usage and sub-activities of an activity) which are vital for accurate wellness analysis and determination. As a result, the classifier is trained in a more logical manner in the context of behavior parameters which are more relevant for wellness determination. The frequent behavioral patterns are classified using the lazy associative classifier (LAC) for wellness determination. The associative nature of LAC helps to integrate spatial–temporal and related contextual attributes (provided by CDEA) of elderly behavior to generate behavior-focused classification rules. Similarly, LAC provides high accuracy with less training time of the classifier, includes minimum-support behavior patterns, and selects highly accurate classification rules for the classification of a test instance. CAAWD further introduces the ability to contextually validate the authenticity of the already classified instance by taking behavioral contextual information (of the elderly person) from the caregiver. Due to the consideration of spatial–temporal behavior contextual attributes, the use of an efficient classifier, and the ability to contextually validate the classified instances, it has been observed that the CAAWD model out-performs currently proposed techniques in terms of accuracy, precision, and f-measure.

Effects of Obesity and Fall Risk on Gait and Posture of Community-Dwelling Older Adults

Epidemiological studies link increased fall risk to obesity in older adults, but the mechanism through which obesity increases falls and fall risks is unknown. This study investigates if obesity (Body Mass Index: BMI>30 kg/m²) influenced gait and standing postural characteristics of community dwelling older adults leading to increased risk of falls. One hundred healthy older adults (age 74.0±7.6 years, range of 56-90 years) living independently in a community participated in this study. Participants' history of falls over the previous two years was recorded, with emphasis on frequency and characteristics of falls. Participants with at least two falls in the prior year were classified as fallers. Each individual was assessed for postural stability during quiet stance and gait stability during 10 meters walking. Fall risk parameters of postural sway (COP area, velocity, path-length) were measured utilizing a standard forceplate coupled with an accelerometer affixed at the sternum. Additionally, parameters of gait stability (walking velocity, double support time, and double support time variability) were assessed utilizing an accelerometer affixed at the participant's sternum. Gait and postural stability analyses indicate that obese older adults who fell have significantly altered gait pattern (longer double support time and greater variability) exhibiting a loss of automaticity in walking and, postural instability as compared to their counterparts (i.e., higher sway area and path length, and higher sway velocity) further increasing the risk of a fall given a perturbation. Body weight/BMI is a risk factor for falls in older adults as measured by gait and postural stability parameters.

Vitamin D deficiency adversely affects early post-operative functional outcomes after total knee arthroplasty

PURPOSE

Vitamin D has received considerable attention in recent years owing to the increasing evidence of its importance in muscle function and physical performance. The present study attempted to determine whether patients with low serum vitamin D levels had impairment in early functional outcomes following total knee arthroplasty (TKA).

METHODS

This was a prospective cohort study that included 92 patients. Patients were divided into two groups according to their vitamin D levels as assessed at the preoperative visit: (1) vitamin D-deficient group, serum 25-hydroxyvitamin D₃ (25(OH)D) levels <12 ng/mL; (2) vitamin D non-deficient group, serum 25(OH)D levels ≥12 ng/mL. American Knee Society Score (KSS) and four other performance tests including the alternative step test (AST), six-metre walk test (SMT), sit-to-stand test (STS), and timed up and go test (TUGT) were used for assessment of post-operative function. All assessments were performed one day before and three months after TKA.

RESULTS

Of the 92 patients included in the study, 87 patients performed all required assessments. The mean post-operative functional KSS was significantly lesser in the vitamin D-deficient group than in the vitamin D non-deficient group (67.2 vs. 73.4, p = 0.031). The mean values of time taken for post-operative AST (16.6 vs. 14.6 s, p = 0.033) and SMT (8.8 vs. 7.7 s, p = 0.012) were significantly longer in the vitamin D-deficient group than in the vitamin D non-deficient group. Post-operative STS and TUGT demonstrated higher values for mean time taken in the vitamin D-deficient group than in the vitamin D non-deficient group, but these were not statistically significant (13.6 vs. 12.4 s, not significant (n.s.); 12.7 vs. 11.7 s, n.s., respectively).

CONCLUSION

Early post-operative functional outcomes following TKA appear to be adversely affected by vitamin D deficiency.

LEVEL OF EVIDENCE

Prospective cohort study, Level II.

Relationships among Disability, Quality of Life, and Physical Fitness in Lumbar Spinal Stenosis: An Investigation of Elderly Korean Women

STUDY DESIGN

A cross-sectional, case-control study.

PURPOSE

To investigate associations between physical fitness measures and disabilities related to back pain and quality of life (QOL) by the presence of symptomatic lumbar spinal stenosis (LSS) in elderly Korean women.

OVERVIEW OF LITERATURE

LSS leads to decreased functioning and reduced QOL. However, correlations among physical fitness, disability, and QOL have not been investigated in elderly women with LSS.

METHODS

Participants included women aged 65 years and older (n=192), divided into a study group (n=38) and a control group (n=154) based on the presence/absence of LSS. All participants underwent physical function and fitness tests. Oswestry disability index (ODI) scores and EuroQol five-dimensional questionnaire (EQ-5D-5L) scores were used to assess disability and health-related QOL.

RESULTS

The results for the handgrip strength, sit-and-reach, functional reach, and timed up and go (TUG) tests were significantly higher in the control group than the LSS group. ODI scores were significantly higher and EQ-5D-5L scores significantly lower in the LSS group. TUG and functional reach test scores were significantly correlated with ODI scores, and handgrip strength was strongly interrelated with ODI and EQ-5D-5L scores in the LSS group. No other physical fitness measures showed statistically significant relationships with ODI or EQ-5D-5L scores.

CONCLUSIONS

In elderly Korean women with LSS, back pain-related disability and QOL are significantly associated with some physical fitness parameters such as handgrip strength. Handgrip strength reflects general muscle strength, which is significantly interrelated with the level of disability and QOL. Our results suggest that enhancing generalized muscle strength helps to reduce disability due to back pain and improve QOL in patients with LSS.

DNA damage markers in dermal fibroblasts in vitro reflect chronological donor age

The aging process is accompanied by an accumulation of cellular damage, which compromises the viability and function of cells and tissues. We aim to further explore the association between in vitro DNA damage markers and the chronological age of the donor, as well as long-lived family membership and presence of cardiovascular diseases. Therefore, numbers of 53BP1 foci, telomere-associated foci (TAF) and micronuclei were measured in cultured dermal fibroblasts obtained from three age groups of donors (mean age 22, 63 and 90 years). Fibroblasts were cultured without a stressor and with 0.6 μM rotenone for 3 days. We found that 53BP1 foci and TAF were more frequently present in fibroblasts of old donors compared to middle-aged and young donors. No association between micronuclei and donor age was found. Within the fibroblasts of the middle-aged donors we did not find associations between DNA damage markers and long-lived family membership or cardiovascular disease. Results were comparable when fibroblasts were stressed in vitro with rotenone. In conclusion, we found that DNA damage foci of cultured fibroblasts are significantly associated with the chronological age, but not biological age, of the donor.

Impact of physical and mental health on life satisfaction in old age: a population based observational study

Background

It is widely assumed that poor health lowers life satisfaction when ageing. Yet, research suggests this relationship is not straightforward. This study investigated how older people evaluate their life when facing disease and disabilities.

Methods

The Leiden 85-plus Study, a prospectively followed cohort of a cohort of a middle-sized city in the Netherlands, all aged 85 years, that was age-representative of the general population, was used. Those with severe cognitive dysfunction were excluded (n = 501). Comorbidities, physical performance, cognitive function, functional status, residual lifespan, depressive symptoms and experienced loneliness were measured during home visits. Life satisfaction was self-reported with Cantril’s ladder. All analyses were performed using regression analysis.

Results

Participants reported high life satisfaction (median 8 out of 10 points) despite having representative levels of disease and disability. Comorbidity, low cognitive function, and residual lifespan as markers of health were not associated with life satisfaction. Poor physical performance and low functional status were weakly but significantly associated with lower life satisfaction (p < 0.05 respectively p < 0.001), but significance was lost after adjustment for depressive symptoms and perceived loneliness. Depressive symptoms and perceived loneliness were strongly related to lower life satisfaction (both p < 0.001), even after adjustment for physical health characteristics.

Conclusion

Poor physical health was hardly related to lower life satisfaction, whereas poor mental health was strongly related to lower life satisfaction. This indicates that mental health has a greater impact on life satisfaction at old age than physical health, and that physical health is less relevant for a satisfactory old age.

The Association Between Excessive Daytime Sleepiness and Gait Parameters in Community-Dwelling Older Adults: Cross-Sectional Findings From the Obu Study of Health Promotion for the Elderly

OBJECTIVE

This study examined the association between excessive daytime sleepiness (EDS) and gait characteristics (e.g., speed, variability) in community-dwelling older adults.

METHOD

This cross-sectional study included 3,901 individuals aged ≥65 years. Participants answered questions about EDS, sleep duration, and other sleep-related symptoms. Gait speed, stride length, and the variability in stride length were assessed by using a stopwatch and a WalkWay device.

RESULTS

EDS was significantly associated with slower gait speed among younger subjects (<75 years, p = .021) and with both slower gait speed ( p = .045) and greater variability in stride length among older subjects (≥75 years, p = .048) in a multivariate analysis adjusted for age, sex, body mass index, medication, number of comorbidities, and education.

DISCUSSION

EDS associates with gait ability, particularly in older old adults. Further prospective studies are needed to determine the causal association between gait ability and sleep disturbances, including EDS.

Associations of Various Health-Ratings with Geriatric Giants, Mortality and Life Satisfaction in Older People

Self-rated health is routinely used in research and practise among general populations. Older people, however, seem to change their health perceptions. To accurately understand these changed perceptions we therefore need to study the correlates of older people's self-ratings. We examined self-rated, nurse-rated and physician-rated health's association with common disabilities in older people (the geriatric giants), mortality hazard and life satisfaction. For this, we used an age-representative population of 501 participant aged 85 from a middle-sized city in the Netherlands: the Leiden 85-plus Study. Participants with severe cognitive dysfunction were excluded. Participants themselves provided health ratings, as well as a visiting physician and a research nurse. Visual acuity, hearing loss, mobility, stability, urinal and faecal incontinence, cognitive function and mood (depressive symptoms) were included as geriatric giants. Participants provided a score for life satisfaction and were followed up for vital status. Concordance of self-rated health with physician-rated (k = .3 [.0]) and nurse-rated health (k = .2 [.0]) was low. All three ratings were associated with the geriatric giants except for hearing loss (all p < 0.001). Associations were equal in strength, except for depressive symptoms, which showed a stronger association with self-rated health (.8 [.1] versus .4 [.1]). Self-rated health predicted mortality less well than the other ratings. Self-rated health related stronger to life satisfaction than physician's and nurse's ratings. We conclude that professionals' health ratings are more reflective of physical health whereas self-rated health reflects more the older person's mental health, but all three health ratings are useful in research.

Hypertension and aging

Hypertension is a highly prevalent condition with numerous health risks, and the incidence of hypertension is greatest among older adults. Traditional discussions of hypertension have largely focused on the risks for cardiovascular disease and associated events. However, there are a number of collateral effects, including risks for dementia, physical disability, and falls/fractures which are increasingly garnering attention in the hypertension literature. Several key mechanisms--including inflammation, oxidative stress, and endothelial dysfunction--are common to biologic aging and hypertension development and appear to have key mechanistic roles in the development of the cardiovascular and collateral risks of late-life hypertension. The objective of the present review is to highlight the multi-dimensional risks of hypertension among older adults and discuss potential strategies for treatment and future areas of research for improving overall care for older adults with hypertension.

Usual and Dual-Task Walking Speed

Objective: In many countries, pedestrian light crossings require a minimum walking speed of 1.2 m/s. This study examined the proportion of adults in a nationally representative sample whose usual and dual-task walking speeds are <1.2 m/s. Method: Community-dwelling adults aged ≥50 years in The Irish Longitudinal Study on Ageing (TILDA) completed walking speed tests on a GAITRite® walkway ( N = 4,909). Results: One third of Irish adults aged 65 to 74 years and 61% of adults aged ≥75 years walked slower than 1.2 m/s. In dual-task walking, 54% of adults aged <65 years and 91% of adults aged ≥75 years walked slower than 1.2 m/s. Discussion: Based on these data, many older people would have insufficient time to cross the road at light-controlled pedestrian crossings. Increasing the time provided would be an advantage for many older pedestrians.

"Feeling younger, walking faster": subjective age and walking speed in older adults

Walking speed is a key vital sign in older people. Given the implications of slower gait speed, a large literature has identified health-related, behavioral, cognitive, and biological factors that moderate age-related decline in mobility. The present study aims to contribute to existing knowledge by examining whether subjective age, how old or young individuals experience themselves to be relative to their chronological age, contributes to walking speed. Participants were drawn from the 2008 and 2012 waves of the Health and Retirement Study (HRS, N = 2970) and the 2011 and 2013 waves of the National Health and Aging Trends Study (NHATS, N = 5423). In both the HRS and the NHATS, linear regression analysis revealed that a younger subjective age was associated with faster walking speed at baseline and with less decline over time, controlling for age, sex, education, and race. These associations were partly accounted for by depressive symptoms, disease burden, physical activity, cognition, body mass index, and smoking. Additional analysis revealed that feeling younger than one's age was associated with a reduced risk of walking slower than the frailty-related threshold of 0.6 m/s at follow-up in the HRS. The present study provides novel and consistent evidence across two large prospective studies for an association between the subjective experience of age and walking speed of older adults. Subjective age may help identify individuals at risk for mobility limitations in old age and may be a target for interventions designed to mitigate functional decline.

Consequences of interaction of functional, somatic, mental and social problems in community-dwelling older people

This study explores the combination of four common health problems in older people and whether problems on four domains result in an additional effect on indicators of poor health. For this purpose, a total of 2681 participants (32% male, mean age 82 years) of the Integrated Systematic Care for Older People (ISCOPE) study were screened on the presence of health problems on four domains (functional, somatic, mental, social) with the postal ISCOPE questionnaire. Extensive interview data on health indicators were obtained at baseline and at 12-months follow-up, including disability (Groningen Activities Restriction Scale, GARS), cognitive function (Mini-Mental State Examination, MMSE), depressive symptoms (Geriatric Depression Scale-15, GDS), loneliness (loneliness scale of De Jong Gierveld), and health-related quality of life (EQ-5D). General practitioner (GP) contact time (min/year) was estimated via GP electronic medical records. Of the study population, 9% had no health problems according to the screening, 8% had problems on one domain, 27% on two, 38% on three and 18% on four domains. At baseline, the number of health domains with problems was associated with poorer scores on the GARS, the MMSE, the GDS-15, the loneliness scale, the EQ-5D and with more GP contact time (p <0.001). Problems on all four domains had an additional negative effect on these health indicators (all p_interaction <0.001). At follow-up, an increased number of domains with problems was associated with an increased decline in health indicators (all p<0.001) and with an additional negative effect on GP contact time of the presence of problems on all four domains (p_interaction <0.001). We conclude that combinations of functional, somatic, mental and social problems are associated with poor health indicators in community-dwelling older people. Since problems on four domains have an additional effect on health, individuals with combined functional, somatic, mental and social problems could benefit from integrated care.

Physiological factors contributing to mobility loss over 9 years of follow-up—results from the InCHIANTI study

BACKGROUND

Mobility is an essential aspect of everyday life and enables autonomy and participation. Although many risk factors for mobility loss have been previously described, their relative importance and independent contributions to the long-term risk of losing mobility have not been well defined.

METHODS

This study is based on 1,013 men and women aged ≥65 years enrolled in 1998-2000 and followed for 9 years through 2007-2008 in the population-based InCHIANTI (Invecchiare in Chianti, aging in the Chianti area) study. We considered 44 different measures assessed at baseline to explore six subsystems: (i) central nervous system, (ii) peripheral nervous system, (iii) muscles, (iv) bone and joints, (v) energy production and delivery, and (vi) perceptual system. The outcome was incident mobility loss defined as self-report of inability to walk 400 m or climb and descend 10 steps without help from another person. Random survival forest analysis was used to rank the candidate predictors by their importance.

RESULTS

The most important physiological markers predicting mobility loss that emerged from the random survival forest modeling were older age among women (81-95 vs 65-68 years, hazard ratio [HR] 9.60 [95% CI 3.35, 27.50]), weaker ankle dorsiflexion strength (lowest vs highest quintile, HR 5.25 [95% CI 2.35, 11.72]), low hip flexion range of motion (lowest vs highest quintile, HR 2.30 [95% CI 1.20, 4.41]), presence of primitive reflexes (yes vs no, HR 1.47 [95% CI 1.03, 2.09]), and tremor (yes vs no, HR 1.91 [95% CI 1.18, 3.07]).

CONCLUSION

Prevention of mobility loss with aging should focus on prevention and treatment of neuromuscular impairments.

Comorbidity and functional trajectories from midlife to old age: the Health and Retirement Study

Background.

The number of diseases and physical functioning difficulties tend to increase with age. The aim of this study was to examine the trajectories of physical functioning across age groups and whether the trajectories differ according to disease status in different population subgroups.

Methods.

Repeat data from a nationally representative population sample, the Health and Retirement Study, was used. Participants were 10,709 men and 13,477 women aged 60–107 years at baseline with biennial surveys from 1992 to 2010. Average length of follow-up was 10.3 years ranging from 0 to 18 years. Disease status and physical functioning was asked about at all study phases and 10 items were summed to obtain a physical functioning score (0–10).

Results.

Age modified the relationship between number of chronic diseases and physical functioning with older participants having more physical functioning difficulties with increasing number of diseases. An average 70-year-old participant with no diseases had 0.89 (95% CI: 0.85–0.93) physical functioning difficulties, with one disease 1.72 (95% CI: 1.69–1.76) difficulties, with two diseases 2.57 (95% CI: 2.52–2.62) difficulties, and with three or more diseases 3.82 (95% CI: 3.76–3.88) difficulties. Of the individual diseases memory-related diseases, stroke, pulmonary diseases, and arthritis were associated with significantly higher physical functioning difficulties compared with other diseases.

Conclusions.

Comorbidity is associated with greater burden of physical functioning difficulties. Of the studied diseases, memory-related diseases, stroke, pulmonary diseases, and arthritis alone or in combination limit most physical functioning.

Comparison of Effects of Nonoperative Treatment and Decompression Surgery on Risk of Patients with Lumbar Spinal Stenosis Falling: Evaluation with Functional Mobility Tests

BACKGROUND

Falls are a major factor contributing to fragility fractures. Patients with lumbar spinal stenosis have an increased risk of falling. We are aware of no prior report demonstrating the effect of medical treatment and decompression surgery on the risk of patients with lumbar spinal stenosis falling.

METHODS

From June to November 2011, seventy-six patients were enrolled into the surgery group and fifty patients, into the nonoperative group. Four functional mobility tests, including the Alternate-Step test, Six-Meter Walk test, Sit-to-Stand test, and timed "Up & Go" test, were used to evaluate the risk of falling. The Oswestry Disability Index (ODI) and the EuroQoL-5D (EQ-5D) visual analog scale (VAS) were utilized to assess clinical improvement.

RESULTS

The mean age was 62.4 years in the surgery group and 64.6 years in the nonoperative group. The results of the Alternate-Step test significantly improved during the follow-up period in the surgery group (p = 0.001). However, the results of the Alternate-Step test significantly worsened during the follow-up period in the nonoperative group (p = 0.001). Comparison between the two groups showed more significant improvement in the surgery group, especially for the Six-Meter Walk test at one year postoperatively (p = 0.042) and for the timed "Up & Go" test at three months and one year (p = 0.046 and 0.000). However, the ODI and EQ-5D VAS scores improved in both groups. In a linear mixed model, age, surgery, and the presence of an osteoporotic compression fracture significantly affected the test results related to the risk of falling (p < 0.05).

CONCLUSIONS

The surgery group showed a greater decrease in the risk of falling than those in the nonoperative group. Improved physical performance, including walking and balancing, after decompression lumbar spinal surgery reduces the future risk of falling.

LEVEL OF EVIDENCE

Therapeutic Level II. Retrospective analysis of prospectively collected data. See Instructions for Authors for a complete description of levels of evidence.

Tablet-based strength-balance training to motivate and improve adherence to exercise in independently living older people: part 2 of a phase II preclinical exploratory trial

BACKGROUND

Home-based exercise programs can improve physical functioning and health status of elderly people. Successful implementation of exercise interventions for older people presents major challenges and supporting elderly people properly while doing their home-based exercises is essential for training success. We developed a tablet-based system-ActiveLifestyle-that offers older adults a home-based strength-balance training program with incorporated motivation strategies and support features.

OBJECTIVE

The goal was to compare 3 different home-based training programs with respect to their effect on measures of gait quality and physical performance through planned comparisons between (1) tablet-based and brochure-based interventions, (2) individual and social motivation strategies, and (3) active and inactive participants.

METHODS

A total of 44 autonomous-living elderly people (mean 75, SD 6 years) were assigned to 3 training groups: social (tablet guided, n=14), individual (tablet guided, n=13), and brochure (brochure guided, n=17). All groups joined a 12-week progressive home-based strength-balance training program. Outcome measures were gait performance under single and dual task conditions, dual task costs of walking, falls efficacy, and physical performance as measured by the Short Physical Performance Battery (SPPB). Furthermore, active (≥75% program compliance) and inactive (<75% program compliance) individuals were compared based on their characteristics and outcome measures.

RESULTS

The tablet groups showed significant improvements in single and dual task walking, whereas there were no significant changes observable in the brochure group. Between-groups comparisons revealed significant differences for gait velocity (U=138.5; P=.03, r=.33) and cadence (U=138.5, P=.03 r=.34) during dual task walking at preferred speed in favor of the tablet groups. The brochure group had more inactive participants, but this did not reach statistical significance (U=167, P=.06, r=.29). The active participants outperformed the inactive participants in single and dual task walking, dual task costs of walking, and SPPB scores. Significant between-groups differences were seen between the tablet groups and the brochure group, in favor of the tablet groups.

CONCLUSIONS

A tablet-based strength-balance training program that allows monitoring and assisting autonomous-living older adults while training at home was more effective in improving gait and physical performance when compared to a brochure-based program. Social or individual motivation strategies were equally effective. The most prominent differences were observed between active and inactive participants. These findings suggest that in older adults a tablet-based intervention enhances training compliance; hence, it is an effective way to improve gait.

What physical attributes underlie self-reported vs. observed ability to walk 400 m in later life? An analysis from the InCHIANTI Study

OBJECTIVE

The aims of this study were to evaluate and contrast the physical attributes that are associated with self-reported vs. observed ability to walk 400 m among older adults.

DESIGN

Analysis of baseline and 3-yr data from 1026 participants 65 yrs or older in the InCHIANTI (Invecchiare in Chianti) study was conducted. Observed and self-reported ability to walk 400 m at baseline and at 3 yrs were primary outcomes. Predictors included leg speed, leg strength, leg strength symmetry, range of motion, balance, and kyphosis.

RESULTS

Balance, leg speed, leg strength, kyphosis, leg strength symmetry, and knee range of motion were associated with self-reported ability to walk 400 m at baseline (P < 0.001, c = 0.85). Balance, leg speed, and knee range of motion were associated with observed 400-m walk (P < 0.001, c = 0.85) at baseline. Prospectively, baseline leg speed and leg strength were predictive of both self-reported (P < 0.001, c = 0.79) and observed (P < 0.001, c = 0.72) ability to walk 400 m at 3 yrs.

CONCLUSIONS

The profiles of attributes that are associated with self-reported vs. observed walking ability differ. The factor most consistently associated with current and future walking ability is leg speed. These results draw attention to important foci for rehabilitation.

Association of physical workload and leisure time physical activity with incident mobility limitations: a follow-up study

OBJECTIVES

To examine individual as well as joint associations of physical workload and leisure time physical activity with incident mobility limitations in initially well-functioning middle-aged workers.

METHODS

This study is based on 6-year follow-up data of the Danish Longitudinal Study on Work, Unemployment and Health. Physical workload was reported at baseline and categorised as light, moderate or heavy. Baseline leisure time physical activity level was categorised as sedentary or active following the current recommendations on physical activity. Incidence of mobility limitations in climbing stairs and running among initially well-functioning workers (n=3202 and n=2821, respectively) was assessed during follow-up.

RESULTS

Higher workload increased whereas active leisure time decreased the risk of developing mobility limitations. The incidence of limitations increased progressively with higher workload regardless of level of leisure time physical activity, although the risks tended to be higher among those with sedentary leisure time compared with their active counterparts. All in all, the risk for onset of mobility limitations was highest among those with heavy workload combined with sedentary leisure time and lowest among those with light workload combined with active leisure time.

CONCLUSIONS

Although leisure time physical activity prevents development of mobility decline, high workload seems to accelerate the progression of mobility limitations among both those with active and sedentary leisure time. Therefore, efforts should be made to recommend people to engage in physical activity regardless of their physical workload.

Functioning of obese individuals in pre- and postoperative periods of bariatric surgery

BACKGROUND

Obesity is a pathologic condition that causes functional incapacity, with reduction of quality of life and life expectancy and an increase in mortality. Bariatric surgery is indicated to alleviate associated comorbidities and increase physical capacity. The objective of this work was to evaluate the functional capacity of patients with morbid obesity before and after (3 months) bariatric surgery.

METHODS

This was a cross-sectional study involving 67 patients, where 61 were women and six men, with a mean age of 38 ± 10 years and mean BMI of 50.45 ± 8.5 kg/m2. All patients were assessed before surgery and 3 months afterwards. The following assessments were performed: 6-min walk test (6MWT), functional independence measure (FIM), and test for risk of falling and transfer capacity, called the timed up-and-go test.

RESULTS

The study demonstrated a reduction in parameters evaluated in 6MWT with a statistically significant difference at two times (rest and final) when evaluated before and after bariatric surgery (p < 0.001). In relation to the FIM and timed up-and-go test, the patients showed a statistically significant improvement (p < 0.001) for both when comparing the tasks evaluated at the pre- and postoperative moments.

CONCLUSIONS

Obesity has an impact on the functioning and quality of life of patients. We observed an improvement in all instruments used for assessment before and after bariatric surgery, where a linear component was demonstrated in relation to diminution of body mass index and functioning.

MicroRNA-663 induction upon oxidative stress in cultured human fibroblasts depends on the chronological age of the donor

MicroRNAs, regulators of messenger RNA translation, have been observed to influence many physiological processes, amongst them the process of aging. Higher levels of microRNA-663 (miR-663) have previously been observed in human dermal fibroblasts subject to both replicative and stress-induced senescence compared to early passage cells. Also, higher levels of miR-663 have been found in memory T-cells and in human fibroblasts derived from older donors compared to younger donors. In previous studies we observed that dermal fibroblasts from donors of different chronological and biological age respond differentially to oxidative stress measured by markers of cellular senescence and apoptosis. In the present study we set out to study the association between miR-663 levels and chronological and biological age. Therefore we tested in a total of 92 human dermal fibroblast strains whether the levels of miR-663 in non-stressed and stressed conditions (fibroblasts were treated with 0.6 μM rotenone in stressed conditions) were different in young, middle aged and old donors and whether they were different in middle aged donors dependent on their biological age, as indicated by the propensity for familial longevity. In non-stressed conditions the level of miR-663 did not differ between donors of different age categories and was not dependent on biological age. Levels of miR-663 did not differ dependent on biological age in stressed conditions either. However, for different age categories the level of miR-663 in stressed conditions did differ: the level of miR-663 was higher at higher age categories. Also, the ratio of miR-663 induction upon stress was significantly higher in donors from older age categories. In conclusion, we present evidence for an association of miR-663 upon stress and chronological age.

The contribution of diseases to the male-female disability-survival paradox in the very old: results from the Newcastle 85+ study

Background

Explanations for the male-female disability-survival paradox - that woman live longer than men but with more disability - include sex differences in diseases and their impact on disability and death. Less is known about the paradox in the very old. We examine sex differences in the presence and impact of disabling and fatal diseases accounting for the male-female disability-survival paradox in very late life.

Methods

We use data from the Newcastle 85+ Study, a cohort of people born in 1921 and all recruited at age 85 in 2006. Participants underwent a health assessment (HA) at baseline, 18 months, 36 months, 60 months, and a review of their GP records (GPRR) at baseline and 36 months. We used multi-state modelling to assess the impact of specific diseases on disability and death. Disability (measured via ADLs/IADLs) was categorised as no disability (difficulty with 0 activities), or disabled (difficulty with one or more activities). Diseases were ascertained from review of general practice records and cognitive impairment which was defined as an sMMSE of 21 or less (from health assessment).

Results

In participants who had complete HA and GPRR, women had more arthritis (RR = 1.2, 95% CI: 1.1–1.3) and hypertension (RR = 1.2, 95%CI 1.0–1.3), more disability, and were more likely disabled at all follow-ups. From multistate models, women with cerebrovascular disease (HR: 2.6, 95% CI: 2.1–3.4) or respiratory disease (HR: 2.0, 95% CI: 1.4–3.0) were more likely to become disabled than those without but this did not hold for men (sex difference p<0.01). Men were more likely to die from respiratory disease (HR: 2.2, 95% CI: 1.8–2.8) but this did not hold for women (p = 0.002).

Conclusion

The disability-survival paradox was still evident at age 85 and appears due to sex differences in the types of diseases and their impact on the disability pathway.

Disability transitions in the oldest old in the general population. The Leiden 85-plus study

Transitions between disability states in older people occur frequently. This study investigated predictors of disability transitions in the oldest old and was performed in the Leiden 85-plus study, a population-based prospective cohort study among 597 participants aged 85 years. At baseline (age 85 years), data on sociodemographic characteristics and chronic diseases were obtained. Disabilities in basic activities of daily living (BADL) and instrumental activities of daily living (IADL) were measured annually for 5 years with the Groningen Activities Restriction Scale (GARS). Mortality data were obtained. A statistical multi-state model was used to assess the risks of transitions between no disabilities, IADL disability, BADL disability, and death. At baseline, 299 participants (50.0 %) were disabled in IADL only, and 155 participants (26.0 %) were disabled in both BADL and IADL. During 5-year follow-up, 374 participants (62.6 %) made >1 transition between disability states, mostly deterioration in disability. Males had a lower risk of deterioration [hazard ratio (HR), 0.75 (95 % CI, 0.58-0.96)] compared to females. No gender differences were observed for improvement [HR, 0.64 (95 % CI, 0.37-1.11)]. Participants with depressive symptoms were less likely to improve [HR, 0.50 (95 % CI, 0.28-0.87)]. Participants with depressive symptoms [HR, 1.46 (95 % CI, 1.12-1.91)], >1 chronic disease [HR, 1.60 (95 % CI, 1.27-2.01)], and with cognitive impairment [HR, 1.60 (95 % CI, 1.20-2.13)] had the highest risk of deteriorating. Disability is a dynamic process in the oldest old. Deterioration is more common than improvement. Older men are less likely to deteriorate than women. The presence of depressive symptoms, chronic disease, and cognitive impairment predicts deterioration.

Neighborhood amenities and mobility in older adults

Diversity of neighborhood amenities may promote the mobility of older adults. A 2010 community-based sample of 510 adults aged ≥65 years in Philadelphia, Pennsylvania, and geospatial data from the Esri Business Analyst database (Esri, Inc., Redlands, California) were used to assess associations of neighborhood amenity diversity with mobility. Neighborhoods were defined by census tract, and diversity of amenities was derived by using the Leadership in Energy and Environmental Design's neighborhood development index (US Green Building Council, Washington, DC). Generalized estimating equations adjusted for demographic, socioeconomic, and neighborhood characteristics were used to estimate differences in mobility score by tertile of amenity diversity. Analyses were stratified by participants' routine travel habits (stayed at home, stayed in home zip code, or traveled beyond home zip code). We found that for those who spent most of their time in their home neighborhoods, mobility scores (from the Life-Space Assessment, which ranges from 0 to 104 points) were 8.3 points higher (95% confidence interval: 0.1, 16.6) among those who lived in neighborhoods with the most amenity diversity compared with those who lived in neighborhoods with the least amenity diversity. No significant associations between amenity diversity and mobility were observed for those who did not leave home or who regularly traveled outside their neighborhoods. Neighborhoods with a high diversity of amenities may be important promoters of mobility in older adults who do not routinely travel outside their neighborhoods.

Predicting survival in oldest old people

OBJECTIVE

Measures of physical performance are regarded as useful objective clinical tools to estimate survival in elderly people. However, oldest old people, aged 85 years or more, are underrepresented in earlier studies and frequently unable to perform functional tests. We studied the association of gait speed and survival in a cohort of oldest old people and the association of Instrumental Activities of Daily Living by questionnaire and survival as an alternative prognostic marker of survival.

METHODS

The Leiden 85-plus Study was used, a prospective population-based study with a follow-up period of 12 years. The study comprised 599 participants all aged 85 years at baseline. Survival rate was the measurement.

RESULTS

At age 85 years, 73 participants (12.2%) did not perform the walking test. Gait speed faster than 0.8 m/s was present in only 48 participants (9%), and gait speed faster than 1.0 m/s was present in 10 participants (1.9%). Risk for all-cause mortality was higher in participants with slow gait speed after 2 and 12 years of follow-up (hazard ratio [HR], 2.66; 95% confidence interval [CI], 1.49-4.75; P<.001; and HR, 2.04; 95% CI, 1.61-2.59; P=.100, respectively). Significance was lost after adjustment for common confounders. Poor Instrumental Activities of Daily Living ability was associated with an increased risk of mortality after 2 and 12 years of follow-up (HR, 6.11; 95% CI, 3.44-10.87; P<.001; and HR, 2.75; 95% CI, 2.22-3.40; P<.001, respectively). Adjustment for possible confounders attenuated the relation but remained significant.

CONCLUSIONS

The cutoff points for gait speed in oldest old people need to be reevaluated. In oldest old people aged 85 years, slow gait speed (≤0.40 m/s in women and ≤0.45 m/s in men) and Instrumental Activities of Daily Living disability are both predictors of survival. Assessment of Instrumental Activities of Daily Living could be a better tool for short- and long-term prognostication of survival in oldest old people.

Socioeconomic circumstances, health behaviours and functional limitations in older persons in four Central and Eastern European populations

OBJECTIVES

to investigate functional limitations and their association with socioeconomic factors in four Central and Eastern European populations.

METHODS

a cross-sectional study of random population samples in Novosibirsk (Russia), Krakow (Poland), Kaunas (Lithuania) and six Czech towns participating in the HAPIEE study. Functional limitations (classified into tertiles of the SF-36 physical functioning subscale), socioeconomic circumstances and health behaviours were available for 34,431 subjects aged 45-69 years.

RESULTS

the proportion of subjects in the worst tertile of the functional limitations score (≤80% of the maximum score) ranged from 21% of the men in Kaunas to 48% in Krakow women. In multivariate ordered logistic regression, functional limitations were strongly inversely associated with education and positively with material deprivation and with being economically inactive. Functional limitations were more common in male smokers and less common in alcohol drinkers. Socioeconomic characteristics explained some of the differences in functional limitations between populations. Health behaviours explained some of the differences between social groups in both genders and between populations in women.

CONCLUSION

unexpectedly, functional limitations were not most common in the sample from Russia, the country with the highest mortality rates. All socioeconomic measures were strongly associated with functional limitations and made some contribution towards explaining differences in limitations between populations.

The Boston Rehabilitative Impairment Study of the Elderly: a description of methods

OBJECTIVES

To describe the methods of a longitudinal cohort study among older adults with preclinical disability. The study aims to address the lack of evidence guiding mobility rehabilitation for older adults by identifying those impairments and impairment combinations that are most responsible for mobility decline and disability progression over 2 years of follow-up.

DESIGN

Longitudinal cohort study.

SETTING

Metropolitan-based health care system.

PARTICIPANTS

Community-dwelling primary care patients aged ≥65 years (N=430), with self-reported modification of mobility tasks because of underlying health conditions.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Late Life Function and Disability Instrument (LLFDI) (primary outcome); Short Physical Performance Battery and 400-m walk test (secondary outcomes).

RESULTS

Among 7403 primary care patients identified as being potentially eligible for participation, 430 were enrolled. Participants have a mean age of 76.5 years, are 68% women, and have on average 4.2 chronic conditions. Mean LLFDI scores are 55.5 for Function and 68.9 and 52.3 for the Disability Limitation and Frequency domains, respectively.

CONCLUSIONS

Completion of our study aims will inform development of primary care-based rehabilitative strategies to prevent disability. Additionally, data generated in this investigation can also serve as a vital resource for ancillary studies addressing important questions in rehabilitative science relevant to geriatric care.

Association of chronic diseases and impairments with disability in older adults: a decade of change?

BACKGROUND

Little is known about how the relationship between chronic disease, impairment, and disability has changed over time among older adults.

OBJECTIVE

To examine how the associations of chronic disease and impairment with specific disability have changed over time.

RESEARCH DESIGN

Repeated cross-sectional analysis, followed by examining the collated sample using time interaction variables, of 3 recent waves of the Health and Retirement Study.

SUBJECTS

The subjects included 10,390, 10,621 and 10,557 community-dwelling adults aged 65 years and above in 1998, 2004, and 2008.

MEASUREMENTS

: Survey-based history of chronic diseases including hypertension, heart disease, heart failure, stroke, diabetes, cancer, chronic lung disease, and arthritis; impairments, including cognition, vision, and hearing; and disability, including mobility, complex activities of daily living (ADL), and self-care ADL.

RESULTS

Over time, the relationship of chronic diseases and impairments with disability was largely unchanged; however, the association between hypertension and complex ADL disability weakened from 1998 to 2004 and 2008 [odds ratio (OR) = 1.24; 99% confidence interval (CI), 1.06-1.46; OR = 1.07; 99% CI, 0.90-1.27; OR = 1.00; 99% CI, 0.83-1.19, respectively], as it did for hypertension and self-care disability (OR = 1.32; 99% CI, 1.13-1.54; OR=0.97; 99% CI, 0.82-1.14; OR = 0.99; 99% CI, 0.83-1.17). The association between diabetes and self-care disability strengthened from 1998 to 2004 and 2008 (OR = 1.21; 99% CI, 1.01-1.46; OR = 1.37; 99% CI, 1.15-1.64; OR = 1.52; 99% CI, 1.29-1.79), as it also did for lung disease and self-care disability (OR = 1.64; 99% CI, 1.33-2.03; OR = 1.63; 99% CI, 1.32-2.01; OR = 2.11; 99% CI, 1.73-2.57).

CONCLUSIONS

Although relationships between diseases, impairments, and disability were largely unchanged, disability became less associated with hypertension and more with diabetes and lung disease.

The personal and health service impact of falls in 85 year olds: cross-sectional findings from the Newcastle 85+ cohort study

INTRODUCTION

Falls are common in older people and increase in prevalence with advancing old age. There is limited knowledge about their impact in those aged 85 years and older, the fastest growing age group of the population. We investigated the prevalence and impact of falls, and the overlap between falls, dizziness and blackouts, in a population-based sample of 85 year olds.

METHODS

DESIGN

Cross-sectional analysis of baseline data from Newcastle 85+ Cohort Study.

SETTING

Primary care, North-East England.

PARTICIPANTS

816 men and women aged 85 years.

MEASUREMENTS

Structured interview with research nurse. Cost-consequence analysis of fall-related healthcare costs.

RESULTS

Over 38% (313/816) of participants had fallen at least once in the previous 12 months and of these: 10.6% (33/312) sustained a fracture, 30.1% (94/312) attended an emergency department, and 12.8% (40/312) were admitted to hospital. Only 37.2% (115/309) of fallers had specifically discussed their falls problem with their general practitioner and only 12.7% (39/308) had seen a falls specialist. The average annual healthcare cost per faller was estimated at £202 (inter-quartile range £174-£231) or US$329 ($284-$377). 'Worry about falling' was experienced by 42.0% (128/305) of fallers, 'loss of confidence' by 40.0% (122/305), and 'going out less often' by 25.9% (79/305); each was significantly more common in women, odds ratios (95% confidence interval) for women: men of 2.63 (1.45-4.55), 4.00 (2.27-7.14), and 2.86 (1.54-5.56) respectively. Dizziness and blackouts were reported by 40.0% (318/796) and 6.4% (52/808) of participants respectively. There was marked overlap in the report of falls, dizziness and blackouts.

CONCLUSIONS

Falls in 85 year olds are very common, associated with considerable psychological and physical morbidity, and have high impact on healthcare services. Wider use of fall prevention services is needed. Significant expansion in acute and preventative services is required in view of the rapid growth in this age group.

One walk a year to 1000 within a year: continuous in-home unobtrusive gait assessment of older adults

Physical performance measures predict health and function in older populations. Walking speed in particular has consistently predicted morbidity and mortality. However, single brief walking measures may not reflect a person's typical ability. Using a system that unobtrusively and continuously measures walking activity in a person's home we examined walking speed metrics and their relation to function. In 76 persons living independently (mean age, 86) we measured every instance of walking past a line of passive infra-red motion sensors placed strategically in their home during a four-week period surrounding their annual clinical evaluation. Walking speeds and the variance in these measures were calculated and compared to conventional measures of gait, motor function and cognition. Median number of walks per day was 18±15. Overall mean walking speed was 61±17 cm/s. Characteristic fast walking speed was 96 cm/s. Men walked as frequently and fast as women. Those using a walking aid walked significantly slower and with greater variability. Morning speeds were significantly faster than afternoon/evening speeds. In-home walking speeds were significantly associated with several neuropsychological tests as well as tests of motor performance. Unobtrusive home walking assessments are ecologically valid measures of walking function. They provide previously unattainable metrics (periodicity, variability, range of minimum and maximum speeds) of everyday motor function.

Chronic inhibition of the respiratory chain in human fibroblast cultures: differential responses related to subject chronological and biological age

Respiratory chain function becomes less efficient with age resulting in increased levels of damaging reactive oxygen species. We compared rotenone-exposed fibroblast strains from young and old subjects and from offspring of nonagenarian siblings and the partners of the offspring. Rotenone increased reactive oxygen species levels, inhibited growth rate, and increased telomere shortening (all p < .05). Non-stressed strains from young subjects showed lower reactive oxygen species levels (p = .031) and higher growth rates (p = .002) than strains from old subjects. Stressed strains from young subjects showed smaller increases in reactive oxygen species levels (p = .014) and larger decreases in growth rate (p < .001) than strains from old subjects. Telomere-shortening rates were not different between groups. Stress-induced decreases in growth rate were larger in strains from offspring than from partners (p = .05). Strains from young and old subjects are differentially affected by chronic inhibition of the respiratory chain. Changed growth rates in strains from offspring resemble those from strains from young subjects.

Factors associated with maximal walking speed among older community-living adults

BACKGROUND AND AIMS

The relative contribution of different domains on walking speed is largely unknown. This study investigated the central factors associated with maximal walking speed among older people.

METHODS

Cross-sectional analyses of baseline data from the SCAMOB study (ISRCTN 07330512) involving 605 community-living ambulatory adults aged 75-81 years. Maximal walking speed, leg extensor power, standing balance and body mass index were measured at the research center. Physical activity, smoking, use of alcohol, chronic diseases and depressive symptoms were self-reported by standard questionnaires.

RESULTS

The mean maximal walking speed was 1.4 m/s (range 0.3-2.9). In linear regression analysis, age, gender and body mass index explained 11% of the variation in maximal walking speed. Adding leg extensor power and standing balance into the model increased the variation explained to 38%. Further adjusting for physical activity, smoking status and use of alcohol increased the variation explained by an additional 7%. A minor further increase in variability explained was gained by adding chronic diseases and depressive symptoms to the model. In the final model, the single most important factors associated with walking speed were leg extensor power, standing balance and physical activity, and these associations were similar in men and women and in different body mass index categories.

CONCLUSIONS

Lower extremity impairment and physical inactivity were the central factors associated with slow walking speed among older people, probably because these factors capture the influences of health changes and other life-style factors, potentially leading to walking limitations.

Exercise capacity in patients with severe symptomatic aortic stenosis before and six months after transcatheter aortic valve implantation

Few data exist on the use of the 6-minute walk test (6MWT) to measure the exercise capacity of patients with severe symptomatic aortic stenosis considered at very high surgical risk. The objectives of the present prospective study were (1) to determine the feasibility and safety of the 6MWT as a measure of exercise capacity before and after transcatheter aortic valve implantation (TAVI), and (2) to determine the clinical and hemodynamic parameters associated with the exercise capacity changes in such patients. A total of 64 patients (age 80 ± 8 years, logistic European System for Cardiac Operative Risk Evaluation score 21 ± 15%, Society of Thoracic Surgeons' score 7.5 ± 3.9%) who had undergone successful TAVI were included. The 6MWT was performed within the month before TAVI and at the 6-month follow-up visit. The mean distance walked increased from 165.3 ± 79.7 to 231.7 ± 88.9 m (p <0.0001); however, up to 25% of the patients did not improve or even decreased their exercise capacity. After adjustment for the baseline distance walked, multilinear regression analysis showed that a greater degree of renal dysfunction, as evaluated by the serum creatinine levels (r(2) = 0.05, p = 0.03), lower postprocedural hemoglobin values (r(2) = 0.13, p = 0.0012), and a longer hospitalization length (r(2) = 0.08, p = 0.007) were associated with lower improvement in exercise capacity. In conclusion, exercise capacity, as evaluated by the 6MWT, was very poor in patients with severe symptomatic aortic stenosis considered at very high surgical risk. TAVI was associated with a significant increase in exercise capacity, although no improvement was observed in 1/4 of the patients. A greater degree in renal dysfunction, lower postprocedural hemoglobin values, and longer hospitalization stay were predictors of lower improvement in exercise capacity after TAVI. These results suggest that the 6MWT might become an important tool as a part of the evaluation process for TAVI candidates.

The effect of cognitive impairment on the predictive value of multimorbidity for the increase in disability in the oldest old: the Leiden 85-plus Study

Background: prevention of disability is an important aim of healthcare for older persons. Selection of persons at risk is a first crucial step in this process.

Objectives: this study investigates the predictive value of multimorbidity for the development of disability in the general population of very old people and the role of cognitive impairment in this association.

Design: the Leiden 85-plus Study (1997–2004) is an observational prospective cohort study with 5 years of follow-up.

Setting: general population of the city of Leiden, the Netherlands.

Subjects: population based sample of 594 participants aged 85 years.

Methods: disability in activities of daily living (ADL) was measured annually for 5 years with the Groningen Activity Restriction Scale (range 9–36, 9 = optimal). Multimorbidity is defined as the presence of two or more chronic diseases at age 85 years. Cognitive function was measured at baseline with the mini-mental state examination (MMSE).

Results: at baseline participants with multimorbidity had higher ADL disability scores compared with those without [median 11 inter-quartile range (IQR 9–16) versus 9 (IQR 9–13) ADL points, Mann–Whitney U test P < 0.001]. Stratified into four MMSE groups, ADL disability increased over time in all groups, even in participants without multimorbidity (P trend <0.001). Multimorbidity predicted accelerated increase in ADL disability in participants with MMSE of 28–30 points (n = 205, 0.67 points/year, P < 0.001), but not in participants with lower MMSE scores (all P > 0.100).

Conclusion: the predictive value of multimorbidity for the increase in ADL disability varies with cognitive function in very old people. In very old people with good cognitive function, multimorbidity predicts accelerated increase in ADL disability. This relation is absent in very old people with cognitive impairment.

Functional interplay between mitochondrial and proteasome activity in skin aging

According to the mitochondrial theory of aging, reactive oxygen species (ROS) derived primarily from mitochondria cause cumulative oxidative damage to various cellular molecules and thereby contribute to the aging process. On the other hand, a pivotal role of the proteasome, as a main proteolytic system implicated in the degradation of oxidized proteins during aging, is suggested. In this study, we analyzed mitochondrial function in dermal fibroblasts derived from biopsies obtained from healthy young, middle-aged, and old donors. We also determined proteasome activity in these cells, using a degron-destabilized green fluorescent protein (GFP)-based reporter protein. We found a significant decrease in mitochondrial membrane potential in samples from aged donors, accompanied by a significant increase in ROS levels. Respiratory activity was not significantly altered with donor age, probably reflecting genetic variation. Proteasome activity was significantly decreased in fibroblasts from middle-aged donors compared with young donors; fibroblasts derived from the oldest donors displayed a high heterogeneity in this assay. We also found intraindividual coregulation of mitochondrial and proteasomal activities in all human fibroblast strains tested, suggesting that both systems are interdependent. Accordingly, pharmacological inhibition of the proteasome led to decreased mitochondrial function, whereas inhibition of mitochondrial function in turn reduced proteasome activity.

Physical factors underlying the association between lower walking performance and falls in older people: a structural equation model

The purpose of this study was to determine the interrelationships between lower limb muscle performance, balance, gait and falls in older people using structural equation modeling. Study participants were two hundred and thirteen people aged 65 years and older (mean age, 80.0 ± 7.1 years), who used day-care services in Japan. The outcome measures were the history of falls three months retrospectively and physical risk factors for falling, including performance in the chair stand test (CST), one-leg standing test (OLS), tandem walk test, 6m walking time, and the timed up-and-go (TUG) test. Thirty-nine (18.3%) of the 213 participants had fallen at least one or more times during the preceding 3 months. The fall group had significantly slower 6m walking speed and took significantly longer to undertake the TUG test than the non-fall group. In a structural equation model, performance in the CST contributed significantly to gait function, and low gait function was significantly and directly associated with falls in older people. This suggests that task-specific strength exercise as well as general mobility retraining should be important components of exercise programs designed to reduce falls in older people.

Population attributable risk for functional disability associated with chronic conditions in Canadian older adults

OBJECTIVES

to investigate the population impact on functional disability of chronic conditions individually and in combination.

METHODS

data from 9,008 community-dwelling individuals aged 65 and older from the Canadian Study of Health and Aging (CSHA) were used to estimate the population attributable risk (PAR) for chronic conditions after adjusting for confounding variables. Functional disability was measured using activity of daily living (ADL) and instrumental activity of daily living (IADL).

RESULTS

five chronic conditions (foot problems, arthritis, cognitive impairment, heart problems and vision) made the largest contribution to ADL- and IADL-related functional disabilities. There was variation in magnitude and ranking of population attributable risk (PAR) by age, sex and definition of disability. All chronic conditions taken simultaneously accounted for about 66% of the ADL-related disability and almost 50% of the IADL-related disability.

CONCLUSIONS

in community-dwelling older adults, foot problems, arthritis, cognitive impairment, heart problems and vision were the major determinants of disability. Attempts to reduce disability burden in older Canadians should target these chronic conditions; however, preventive interventions will be most efficient if they recognize the differences in the drivers of PAR by sex, age group and type of functional disability being targeted.