Trajectories of Lower Extremity Physical Performance: Effects on Fractures and Mortality in Older Women

Muscle parameters in fragility fracture risk prediction in older adults: A scoping review

Half of osteoporotic fractures occur in patients with normal/osteopenic bone density or at intermediate or low estimated risk. Muscle measures have been shown to contribute to fracture risk independently of bone mineral density. The objectives were to review the measurements of muscle health (muscle mass/quantity/quality, strength and function) and their association with incident fragility fractures and to summarize their use in clinical practice. This scoping review follows the PRISMA-ScR guidelines for reporting. Our search strategy covered the three overreaching concepts of 'fragility fractures', 'muscle health assessment' and 'risk'. We retrieved 14 745 references from Medline Ovid SP, EMBASE, Web of Science Core Collection and Google Scholar. We included original and prospective studies on community-dwelling adults aged over 50 years that analysed an association between at least one muscle parameter and incident fragility fractures. We systematically extracted 17 items from each study, including methodology, general characteristics and results. Data were summarized in tables and graphically presented in adjusted forest plots. Sixty-seven articles fulfilled the inclusion criteria. In total, we studied 60 muscle parameters or indexes and 322 fracture risk ratios over 2.8 million person-years (MPY). The median (interquartile range) sample size was 1642 (921-5756), age 69.2 (63.5-73.6) years, follow-up 10.0 (4.4-12.0) years and number of incident fragility fractures 166 (88-277). A lower muscle mass was positively/not/negatively associated with incident fragility fracture in 28 (2.0), 64 (2.5) and 10 (0.2 MPY) analyses. A lower muscle strength was positively/not/negatively associated with fractures in 53 (1.3), 57 (1.7 MPY) and 0 analyses. A lower muscle function was positively/not/negatively associated in 63 (1.9), 45 (1.0 MPY) and 0 analyses. An in-depth analysis shows how each single muscle parameter was associated with each fragility fractures subtype. This review summarizes markers of muscle health and their association with fragility fractures. Measures of muscle strength and function appeared to perform better for fracture risk prediction. Of these, hand grip strength and gait speed are likely to be the most practical measures for inclusion in clinical practice, as in the evaluation of sarcopenia or in further fracture risk assessment scores. Measures of muscle mass did not appear to predict fragility fractures and might benefit from further research, on D3-creatine dilution test, lean mass indexes and artificial intelligence methods.

Flagging unusual clusters based on linear mixed models using weighted and self-calibrated predictors

Statistical models incorporating cluster-specific intercepts are commonly used in hierarchical settings, for example, observations clustered within patients or patients clustered within hospitals. Predicted values of these intercepts are often used to identify or "flag" extreme or outlying clusters, such as poorly performing hospitals or patients with rapid declines in their health. We consider a variety of flagging rules, assessing different predictors, and using different accuracy measures. Using theoretical calculations and comprehensive numerical evaluation, we show that previously proposed rules based on the 2 most commonly used predictors, the usual best linear unbiased predictor and fixed effects predictor, perform extremely poorly: the incorrect flagging rates are either unacceptably high (approaching 0.5 in the limit) or overly conservative (eg, much <0.05 for reasonable parameter values, leading to very low correct flagging rates). We develop novel methods for flagging extreme clusters that can control the incorrect flagging rates, including very simple-to-use versions that we call "self-calibrated." The new methods have substantially higher correct flagging rates than previously proposed methods for flagging extreme values, while controlling the incorrect flagging rates. We illustrate their application using data on length of stay in pediatric hospitals for children admitted for asthma diagnoses.

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.

Depressive symptoms and daily living dependence in older adults with type 2 diabetes mellitus: the mediating role of positive and negative perceived stress

BACKGROUND

Higher stress is associated with higher levels of depression and instrumental-activities-of-daily-living (IADL) dependence, and depression is strongly associated with specific IADL disabilities. Accordingly, the aim of this study was to investigate the mediating effect of perceived stress on the association between depression and IADL dependence among older adults with diabetes mellitus (DM).

METHODS

We examined baseline data collected from a longitudinal study that recruited 110 patients with DM aged ≥ 65 years from the endocrinology outpatient clinic of a district hospital. The instruments used for our measurement processes comprised a demographic data sheet and Chinese versions of the Perceived Stress Scale (PSS), the short form of the Geriatric Depression Scale (GDS-S), and the Lawton IADL Scale. We assessed the mediating effects of positive perceived stress (PPS) and negative perceived stress (NPS) after controlling for five covariates by using a regression-based model run through the SPSS macro PROCESS.

RESULTS

We observed negative correlations between GDS-S scores and PPS and between PPS and IADL dependence; we noted positive correlations between GDS-S scores and NPS and between NPS and IADL dependence (all P < 0.01). The indirect effect is coefficient = 0.12, [95% confidence interval = (0.0, 0.33)], suggesting that PPS achieves a mediating effect between depressive symptoms and IADL dependence. However, the NPS does not achieve a mediating effect in the relationship between depressive symptoms and IADL dependence (coefficient = 0.06, 95% CI = - 0.03, 0.15).

CONCLUSIONS

Personal PPS mediates the association between depression and IADL dependence in older adults with DM. This finding suggests that providing patients with psychological education to promote their PPS may help prevent their functional decline.

Predictive factors for one-year mortality after surgery for periprosthetic femoral fracture: A retrospective multicenter (TRON group) study

BACKGROUND

Periprosthetic femoral fracture (PFF) after total hip arthroplasty (THA) or bipolar hip arthroplasty (BHA) represents a challenging situation and the treatment is associated with high rates of complications and mortality. The aims of this multicenter retrospective study were to determine 1-year mortality and to identify predictors associated with mortality, including patient characteristics and surgical factors, in patients undergoing surgery for PFF after THA or BHA.

METHODS

We collected 249 cases of PPF after THA or BHA that were treated in our 11 hospitals (named the TRON group) between January 2010 and December 2019. We excluded patients who were conservatively treated, cases in which the 1-year postoperative outcome was unknown, and Vancouver type A cases. Finally, we analyzed 161 patients. Univariate and multivariate Cox regression analyses were performed to identify factors affecting 1-year mortality. Patient-side factors such as age, BMI, fracture type, and preoperative mobility, and surgical factors such as surgical procedure, time to surgery, and operation time were analyzed respectively.

RESULTS

Eighteen of 161 patients (11.2%) died one year after surgery. The multivariate Cox regression analysis identified older age, wheelchair status before injury, and operation time as independent predictors of 1-year mortality (older age: hazard ratio [HR] 1.07, 95% CI 1.01-1.15, P = 0.048; wheelchair status: HR 5.82, 95% CI 1.01-33.47, P = 0.049; operation time: [HR] 1.01, 95% CI 1.00-1.01, P = 0.00929). Meanwhile, fracture type according to the Vancouver classification, body mass index, presence of previous fragility fractures, type of fixation, blood loss during operation, and time to surgery were not independent predictors of 1-year mortality in this analysis. ConclusionThe 1-year mortality rate after surgery for PPFs patients was 11.2%. Factors associated with older and poor activity of daily living (ADL) performance (e.g., wheelchair status before injury), and longer operative time were associated with 1-year mortality after surgery for PPF. Surgeons should carefully plan treatment according to each patient's condition.

Behavioral and Psychological Factors in Buffering Diabetes-related Disability Development

BACKGROUND

Diabetes is associated with disability development. Healthy behaviors and psychosocial support can help patients manage their disease.

PURPOSE

To examine the role of various behavioral and psychological factors in buffering the effect of diabetes on disability development over time in Taiwanese adults.

METHODS

Data on 5,131 adults aged ≥50 years were obtained from the Taiwan Longitudinal Study on Aging. A cohort sequential multilevel design was employed to analyze the association between behavioral and psychosocial factors and the risk of disability over a 11-year period.

RESULTS

In patients with diabetes, having social support and exercising more than six times a week were associated with 4% and 49% reductions in the risk of disability, respectively (βdiabetes*socialsupport = -0.285, p = .006; βdiabetes*exercise3 = -2.612, p = .007). Exercising more than six times a week had an additional significant protective effect against disability development per year (βdiabetes*exercises3*age = -0.241, p = .038). Depression did not significantly interact with diabetes. However, a trajectory analysis revealed that individuals who had both diabetes and depression had the highest disability score from middle age among all participants.

CONCLUSIONS

Engaging in frequent exercise is the most influential factor for reducing the risk of disability in patients with diabetes. Social support provides an additional benefit for disability prevention in individuals with diabetes.

Walking more, not faster, is associated with bone health in China of community-dwelling older women:A cross-sectional study

AIMS

To examine the association between daily steps and step intensity with bone health in Chinese community-dwelling older women.

METHODS

Data from 1116 women in the Physical Activity and Health in Older Women Study in China, 2021. Three bone parameters: bone quality index (BQI), speed of sound (SOS), and broadband ultrasound attenuation (BUA) were measured in the left heel using an ultrasound bone densitometer and transformed into dichotomous variables from medians. Daily steps and step intensity (slow step time, brisk step time, peak 1-min cadence, peak 30-min cadence, and peak 60-min cadence) were measured using a triaxial accelerometer. Participants with high BQI, SOS, and BUA levels were used as references for logistic regression models to explore the association of daily steps and step intensity with bone health.

RESULTS

Daily steps were positively associated with the BQI (odds ratio [OR] = 0.94, confidence interval [CI] = 0.89,1.00), SOS (OR = 0.93, CI = 0.88,0.99), and BUA (OR = 0.93, CI = 0.88,0.99) among older women. There was no significant association between peak cadence and bone health. Slow step time was positively associated with the BQI (OR = 0.94, CI = 0.90,0.99) and SOS (OR = 0.93, CI = 0.88,0.97), while brisk step time was positively associated with the BQI (OR = 0.89, CI = 0.82,0.97), SOS (OR = 0.87, CI = 0.80,0.94), and BUA (OR = 0.89, CI = 0.82,0.97). Moreover, 10,000 steps/day or more was significantly associated with the BQI (OR = 0.52, CI = 0.33,0.81), SOS (OR = 0.55, CI = 0.35,0.86), and BUA (OR = 0.45, CI = 0.28, 0.70) compared to <6000 steps/day.

CONCLUSION

Increasing the number of daily steps or the duration of walking, whether fast or slow, may benefit the bone health of older women.

Advantages and Disadvantages of Random Forest Models for Prediction of Hip Fracture Risk Versus Mortality Risk in the Oldest Old

Targeted fracture prevention strategies among late-life adults should balance fracture risk versus competing mortality risk. Models have previously been constructed using Fine-Gray subdistribution methods. We used a machine learning method adapted for competing risk survival time to evaluate candidate risk factors and create models for hip fractures and competing mortality among men and women aged 80 years and older using data from three prospective cohorts (Study of Osteoporotic Fractures [SOF], Osteoporotic Fracture in Men study [MrOS], Health Aging and Body Composition study [HABC]). Random forest competing risk models were used to estimate absolute 5-year risk of hip fracture and absolute 5-year risk of competing mortality (excluding post-hip fracture deaths). Models were constructed for both outcomes simultaneously; minimal depth was used to rank and select variables for smaller models. Outcome specific models were constructed; variable importance was used to rank and select variables for inclusion in smaller random forest models. Random forest models were compared to simple Fine-Gray models with six variables selected a priori. Top variables for competing risk random forests were frailty and related components in men while top variables were age, bone mineral density (BMD) (total hip, femoral neck), and frailty components in women. In both men and women, outcome specific rankings strongly favored BMD variables for hip fracture prediction while frailty and components were strongly associated with competing mortality. Model discrimination for random forest models varied from 0.65 for mortality in women to 0.81 for hip fracture in men and depended on model choice and variables included. Random models performed slightly better than simple Fine-Gray model for prediction of competing mortality, but similarly for prediction of hip fractures. Random forests can be used to estimate risk of hip fracture and competing mortality among the oldest old. Modest gains in performance for mortality without hip fracture compared to Fine-Gray models must be weighed against increased complexity. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

Muscle strength and physical performance contribute to and improve fracture risk prediction in older people: A narrative review

Osteoporotic fractures present a major health problem with an increasing prevalence in older people. Fractures are associated with premature mortality, reduced quality of life, subsequent fracture, and increased costs. Hence, it is crucial to identify those at higher risk of fracture. Fracture risk assessment tools incorporated clinical risk factors to improve fracture predictive power over BMD alone. However, fracture risk prediction using these algorithms remains suboptimal, warranting further improvement. Muscle strength and physical performance measurements have been associated with fracture risk. In contrast, the contribution of sarcopenia, the composite condition of low muscle mass, muscle strength and/or physical performance, to fracture risk is unclear. It is uncertain whether this is due to the problematic definition of sarcopenia per se or limitations of the diagnostic tools and cut-off points of the muscle mass component. The recent position statement from the Sarcopenia Definition and Outcomes Consortium confirmed the inclusion of muscle strength and performance in the definition of sarcopenia but not DXA-assessed lean mass. Therefore, clinicians should focus on functional assessment (muscle strength and performance) rather than muscle mass, at least as assessed by DXA, as predictors of fractures. Muscle strength and performance are modifiable risk factors. Resistance exercise improves muscle parameters in the elderly, potentially leading to reduced risk of falls and fractures in the general population and in those who sustained a fracture. Therapists may consider exercise intervention to improve muscle parameters and potentially reduce the risk of fractures. The aim of this review was to explore 1) the contribution of muscle parameters (i.e., muscle mass, strength, and physical performance) to fracture risk in older adults, and 2) the added predictive accuracy of these parameters beyond the existing fracture assessment tools. These topics provide the rationale for investigating strength and physical performance interventions to reduce fracture risk. Most of the included publications showed that muscle mass is not a good predictor of fracture risk, while poor muscle strength and performance are associated with an increased risk of fracture, particularly in men, independent of age, BMD, and other risk factors for fractures. Muscle strength and performance can potentially improve the predictive accuracy in men beyond that obtained by the fracture risk assessment tools, Garvan FRC and FRAX.

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).

Short physical performance battery as a predictor of mortality in community-dwelling older adults: a longitudinal study in the Brazilian Amazon region

Background

The Short Physical Performance Battery (SPPB) is an instrument for assessing physical performance widely used in research among the elderly in multiple settings. We did not find Brazilian longitudinal studies that aimed to analyze the predictive capacity and accuracy of the SPPB among community-dwelling older adults and no systematic reviews were found on the accuracy of the SPPB in predicting mortality in community- dwelling older adults. This study aimed to analyze the capacity and accuracy of the SPPB for predicting mortality in community-dwelling older adults, as well as to determine cut-off points for men and women.

Method

Longitudinal observational study conducted with 411 (70.1 ± 7.25 years) community-dwelling older adults, between 2017 and 2020 (37.7 ± 6.24 months). Physical performance was evaluated using the SPPB and information on the all-cause mortality rate was also recorded. Multivariate Cox regression analyses and curves were performed using the Kaplan-Meier method. Receiver Operating Characteristic (ROC) curves were constructed, with the parameters of area under the ROC curve (AUC) to determine cutoff points for discriminating mortality, considering a significance level of 5% (p < 0.05) and 95% confidence interval (CI) 95%.

Results

Older adults with very low and low physical performance in the SPPB, showed higher risks of mortality (HR = 9.67; 95% CI [1.20-77.65]; HR = 4.06; 95% CI [1.09-15.01]), respectively. In the subtest's analysis, older adults with low performance in the balance (HR = 0.54; 95% CI [0.36-0.81]) and gait speed tests (HR = 0.50; 95% CI [0.33-0.76]) showed greater risks of dying. The same was reproduced for categories in each test (participants that scored 2 points in the balance test had an HR = 5.86; 95% CI [1.84-18.61] and 2 points in the gait speed test, HR = 5.07; 95% CI [1.76-14.58]. The cutoff point ≤ 9 in the SPPB set the discriminator criterion for mortality in older people of both sexes.

Conclusions

The SPPB, as well as the balance and gait speed subtests were predictors of mortality, and the SPPB is accurate in predicting mortality among community-dwelling older adults.

A Matched Cohort Analysis for Examining the Association Between Slow Gait Speed and Shortened Longevity in Older Americans

This investigation examined the association between slow gait speed, as defined with newly established cut-points, and all-cause mortality in older Americans with a matched cohort analysis. The analytic sample included 10,259 Americans aged ≥65 years from the 2006-2014 waves of the Health and Retirement Study. Walking speed was measured in participant residences. Slow gait speed cut-points of <0.60 and <0.75 m/s were used separately for classifying participants as having slow walking speed. Nearest-neighbor propensity score matching was used to match the slow to the not-slow cohorts separately using both cut-points using relevant covariates. Persons with gait speed <0.60 m/s had a 1.42 higher hazard for mortality (95% CI: 1.28-1.57). Older Americans with gait speed <0.75 m/s had a 1.36 higher hazard for mortality (95% CI: 1.23-1.50). Slow gait speed may represent failing health and addressing how slow gait speed could be improved may help with referrals to appropriate interventions.

Risk Factors for the Incident Decline of Physical Performance in Older Men: The Prospective Strambo Study

Risk factors of physical performance decline in older men remain uncertain. We assessed risk factors of incident physical performance deterioration in older men followed up prospectively. In a cohort of 821 men aged 60-87, physical performance was assessed by four tests (five chair stands, standing with closed eyes, forward and backward tandem walk) at baseline, 4 and 8 years. Various predictive biological measurements were performed at baseline. Serum creatinine/ cystatin C (Cr/CysC) ratio was used as an index of muscle mass. In multivariate models, higher age, higher fat mass index (FMI = fat mass/height²), low physical activity, prior stroke and fracture were associated with poor physical performance at baseline. Higher age, low physical activity, low calcium intake, prior non-vertebral fractures, low apparent free testosterone concentration and poor health status were associated with higher risk of loss to follow-up. Low grip strength, Parkinson's disease and stroke were associated with higher risk of incident inability to do five chair stands. Low Cr/CysC ratio and high FMI were associated with high risk of incident inability to perform forward and backward tandem walk. Sarcopenic obesity (co-occurrence of lower tertile of Cr/CysC and upper tertile of FMI) was associated with higher risk of incident inability to perform forward (OR = 3.31, 95% CI 1.88-5.84, p < 0.001) and backward tandem walk and of incident inability to perform more than one test (OR = 5.82, 95% CI 1.29-26.27, p < 0.001). In conclusion, sarcopenic obesity and poor health are associated with higher risk of incident severe decline of physical performance.

Risk factors of falls in elderly patients with visual impairment

OBJECTIVE

To examine the risk factors for falls in elderly patients with visual impairment (VI) and assess the predictive performance of these factors.

METHODS

Between January 2019 and March 2021, a total of 251 elderly patients aged 65-92 years with VI were enrolled and then prospectively followed up for 12 months to evaluate outcomes of accidental falls via telephone interviews. Information of demographics and lifestyle, gait and balance deficits, and ophthalmic and systemic conditions were collected during baseline visits. Forward stepwise multivariable logistic regression analysis was performed to identify independent risk factors of falls in elderly patients with VI, and a derived nomogram was constructed.

RESULTS

A total of 143 falls were reported in 251 elderly patients during follow-up, with an incidence of 56.97%. The risk factors for falls in elderly patients with VI identified by multivariable logistic regression were women [odds ratio (OR), 95% confidence interval (CI): 2.71, 1.40-5.27], smoking (3.57, 1.34-9.48), outdoor activities/3 months (1.31, 1.08-1.59), waking up frequently during the night (2.08, 1.15-3.79), disorders of balance and gait (2.60, 1.29-5.24), glaucoma (3.12, 1.15-8.44), other retinal degenerations (3.31, 1.16-9.43) and best-corrected visual acuity (BCVA) of the better eye (1.79, 1.10-2.91). A nomogram was developed based on the abovementioned multivariate analysis results. The area under receiver operating characteristic curve of the predictive model was 0.779.

CONCLUSIONS

Gender, smoking, outdoor activities, waking up at night, disorders of balance and gait, glaucoma, other retinal degeneration and BCVA of the better eye were independent risk factors for falls in elderly patients with VI. The predictive model and derived nomogram achieved a satisfying prediction of fall risk in these individuals.

How Does Diabetes Accelerate Normal Aging? An Examination of ADL, IADL, and Mobility Disability in Middle-aged and Older Adults With and Without Diabetes

OBJECTIVES

To build an age norm to quantify and compare the different progression rates of disability in people with and without diabetes.

METHODS

Data were extracted from 5,131 adults aged 50 and older from the Taiwan Longitudinal Study in Aging (TLSA) conducted in 1996. Using multilevel mixed models, the disabilities were measured in 1999, 2003, and 2007.

RESULTS

Diabetes accelerated the occurrence and progression of disabilities during aging. Participants with diabetes developed to mobility, IADL, and ADL at the age of 55, near the age of 60, and near the age of 70, respectively. Diabetes accelerated the onset of disabilities of mobility by 3 years, IADL by 7 years, and ADL by 11 years. In the fully adjusted model, diabetes remains a robust predictor for levels of disability (Mobilityβ_DM = 1.668, p < 0.001, IADLβ_DM = 1.031, p < 0.001) (IADβ_DM = 0.690, p < 0.001), and rate of change for developing mobility disability (Mobilityβ_DM*age = 0.088, p < 0.001).

CONCLUSIONS

This study showed that diabetes accelerated the occurrence and progression of disabilities starting in middle age. A three to eleven years of acceleration on disability development on mobility, IADL, and ADL was observed.

The Association Between Walking Speed and Bone Turnover Markers in Older Adults

Background  Previous research conducted among institutionalized older adults has reported increased bone turnover markers (BTMs) in those subjects with mobility limitation. However, the association between walking speed and bone metabolism has not been well described in community-dwelling older adults. Methods The National Health and Nutrition Examination Survey 1999-2000 and 2001-2002 cycles were used to determine the association between the 20-feet walking speed test and bone alkaline phosphatase (BAP) and the cross-linked N-telopeptides of type I bone collagen (NTx). Sex-specific general linear models adjusted for potential confounders were assembled to examine the independent association between the time to complete the walking speed test grouped into quartiles and the logarithmic transformations of BAP and NTx levels.  Results Of 2,521 older adults, 25.8% were defined as having mobility limitation. In both genders, BTM levels progressively increased as the time to complete the walking test also increase. Indeed, women and men who completed the walking speed test in the worst time quartile had on average 6% and 2.8% higher NTx levels than their counterparts who completed the test in the best time quartile, respectively. Likewise, BAP levels also progressively increased across walking speed time quartiles, but to a lesser degree. Notably, NTx levels were 4.7% and 2.6% higher in women and men with mobility limitation than those without, respectively. In contrast, BAP levels did not significantly differ in older adults regardless of their mobility limitation status. Conclusions Community-dwelling older adults with slower walking speeds and mobility limitation consistently had evidence of increased bone resorption. Thus, the present findings indicate that older adults with mobility limitation should be considered at risk of osteoporosis.

Associations between physical function and device-based measures of physical activity and sedentary behavior patterns in older adults: moving beyond moderate-to-vigorous intensity physical activity

Background

Research supports that moderate-to-vigorous intensity physical activity (MVPA) is key to prolonged health and function. Among older adults, substantial changes to MVPA may be infeasible, thus a growing literature suggests a shift in focus to whole-day activity patterns.

Methods

With data from 795 older adults aged 65–100 in the Adult Changes in Thought Activity Monitoring study, we used linear regression to estimate associations between ActiGraph and activPAL measured activity patterns – including light intensity physical activity, steps, standing, and sedentary behaviors – and physical function as measured by a short Performance-based Physical Function (sPPF) score (range 0–12), a composite score based on three standardized physical performance tasks: gait speed, timed chair stands, and grip strength. We examined whether relationships persisted when controlling for MVPA or differed across age, gender, or quartiles of MVPA.

Results

In models unadjusted for MVPA, a 1-standard deviation (SD) increment of daily sitting (1.9 h more), mean sitting bout duration (8 min longer average), or time spent in sedentary activity (1.6 h more) was associated with ~ 0.3–0.4 points lower mean sPPF score (all p < 0.05). A 1-SD increment in daily steps (~ 3500 more steps) was associated with ~ 0.5 points higher mean sPPF score (95% CI: 0.22 to 0.73). MVPA adjustment attenuated all relationships. The association between physical function and steps was strongest among adults aged 75+; associations of worse function with greater sedentary behavior were more pronounced in participants with the lowest levels of MVPA.

Conclusions

We found associations between function and activity metrics other than MVPA in key subgroups, findings that support research on broader activity patterns and may offer ideas regarding practical intervention opportunities for improving function in older adults.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02163-4.

Relationships Between Level and Change in Sarcopenia and Other Body Composition Components and Adverse Health Outcomes: Findings from the Health, Aging, and Body Composition Study

We investigated how baseline values and rates of decline in components of sarcopenia and other body composition parameters relate to adverse clinical outcomes using the Health, Aging, and Body Composition Study. 2689 participants aged 70-79 years were studied. Appendicular lean mass, whole body fat mass, and total hip BMD were ascertained using DXA; muscle strength by grip dynamometry; and muscle function by gait speed. Baseline values and 2-3 year conditional changes (independent of baseline) in each characteristic were examined as predictors of mortality, hospital admission, low trauma fracture, and recurrent falls in the subsequent 10-14 years using Cox regression (generalized estimating equations used for recurrent falls) with adjustment for sex, ethnicity, age, and potential confounders. Lower levels and greater declines in all parameters (excluding hip BMD level) were associated (p < 0.05) with increased rates of mortality; fully-adjusted hazard ratios per SD lower gait speed and grip strength were 1.27 (95% CI 1.19, 1.36) and 1.14 (1.07, 1.21), respectively. Risk factors of hospital admission included lower levels and greater declines in gait speed and grip strength, and greater declines in hip BMD. Lower levels and greater declines in fat mass and hip BMD were associated with low trauma fracture. Lower gait speed, higher fat mass, and both lower levels and greater declines in grip strength were related to recurrent falls. Lower baseline levels and greater declines in musculoskeletal parameters were related to adverse outcomes. Interventions to maximize peak levels in earlier life and reduce rates of age-related decline may reduce the burden of disease in this age group.

Mortality-and Health-Related Factors in a Community-Dwelling of Oldest-Older Adults at the Age of 90: A 10-Year Follow-Up Study

Mortality is obviously intended for epidemiological studies of community-dwelling older adults. There are several health-related factors associated with nutritional status and mortality. The aim of this study was to elucidate the risk factor for mortality in community-dwelling oldest-older adults at the age of 90 and clarify the structure of health-related factors associated with mortality. A 10-year follow-up study was performed for 93 subjects at the age of 90. The mean and median of their survival days were 2373 and 2581 days for women, and 1694 and 1793 days for men. By Cox's proportional hazards model, health-related factors associated with mortality were self-assessed for chewing ability, activities of daily living (ADLs), serum albumin, total cholesterol, serum creatinine, and gripping power for women but not for men. These factors interacted with each other, and the association of these factors was different in women and men. Self-assessed chewing ability was a powerful risk factor for mortality in women at the age of 90. It acted independently from nutritional status. For older adults, addressing healthy food choices together with improved oral functions is useful. However, risk factors for mortality may depend on the life stage of subjects. To investigate the risk factor for the mortality, the life course approach is necessary.

Relation between leg extension power and 30-s sit-to-stand muscle power in older adults: validation and translation to functional performance

This study aimed to assess the validity and functional relevance of a standardized procedure to assess lower limb muscle power by means of the 30-s sit-to-stand (STS) test when compared to leg extension power (LEP), traditional STS performance and handgrip strength. A total of 628 community-dwelling older subjects (60-93 years) from the Copenhagen Sarcopenia Study were included. Physical performance was assessed by the 30-s STS and 10-m maximal gait speed tests. Handgrip strength and LEP were recorded by a hand-held dynamometer and the Nottingham power rig, respectively. STS muscle power was calculated using the subjects' body mass and height, chair height and the number of repetitions completed in the 30-s STS test. We found a small albeit significant difference between LEP and unilateral STS power in older men (245.5 ± 88.8 vs. 223.4 ± 81.4 W; ES = 0.26; p < 0.05), but not in older women (135.9 ± 51.9 vs. 138.5 ± 49.6 W; ES = 0.05; p > 0.05). Notably, a large positive correlation was observed between both measures (r = 0.75; p < 0.001). Relative STS power was more strongly related with maximal gait speed than handgrip strength, repetition-based STS performance and relative LEP after adjusting for age (r = 0.53 vs 0.35-0.45; p < 0.05). In conclusion, STS power obtained from the 30-s STS test appeared to provide a valid measure of bilateral lower limb power and was more strongly related with physical performance than maximal handgrip strength, repetition-based STS performance and LEP.

Mortality Risk Among Older People Who Did Versus Did Not Sustain a Fracture: Baseline Prefracture Strength and Gait Speed as Predictors in a 15-Year Follow-Up

BACKGROUND

Physiological reserve, as indicated by muscle strength and gait speed, may be especially determinant of survival in people who are exposed to a health stressor. We studied whether the association between strength/speed and mortality risk would be stronger in the time period after a fracture compared to other time periods.

METHODS

Participants were population-based sample of 157 men and 325 women aged 75 and 80 years at baseline. Maximal 10-m gait speed and maximal isometric grip and knee extension strength were tested at the baseline before the fracture. Subsequent fracture incidence and mortality were followed up for 15 years. Cox regression analysis was used to estimate fracture time-stratified effects of gait speed and muscle strength on mortality risk in three states: (i) nonfracture state, (ii) the first postfracture year, and (iii) after the first postfracture year until death/end of follow-up.

RESULTS

During the follow-up, 20% of the men and 44% of the women sustained a fracture. In both sexes, lower gait speed and in women lower knee extension strength was associated with increased mortality risk in the nonfracture state. During the first postfracture year, the mortality risk associated with slower gait and lower strength was increased and higher than in the nonfracture state. After the first postfracture year, mortality risk associated with lower gait speed and muscle strength attenuated.

CONCLUSIONS

Lower gait speed and muscle strength were more strongly associated with mortality risk after fracture than during nonfracture time, which may indicate decreased likelihood of recovery.

Decline in Muscle Strength and Performance Predicts Fracture Risk in Elderly Women and Men

CONTEXT

Muscle strength and performance are associated with fractures. However, the contribution of their rate of decline is unclear.

OBJECTIVE

To assess the independent contribution of the rate of decline in muscle strength and performance to fracture risk.

DESIGN, SETTING, AND PARTICIPANTS

Community-dwelling women (n = 811) and men (n = 440) aged 60 years or older from the prospective Dubbo Osteoporosis Epidemiology Study followed from 2000 to 2018 for incident fracture. Clinical data, appendicular lean mass/height2 (ht)2, bone mineral density, quadricep strength/ht (QS), timed get-up-and-go (TGUG), 5 times repeated sit-to-stand (5xSTS), and gait speed (GS) measured biennially. Rates of decline in muscle parameters were calculated using ordinary least squares regression and fracture risk was assessed using Cox's models.

MAIN OUTCOME

Incident low-trauma fracture ascertained by x-ray report.

RESULTS

Apart from lean mass in women, all muscle parameters declined over time. Greater rates of decline in physical performance were associated with increased fracture risk in women (Hazard ratios [HRs] ranging from 2.1 (95% CI: 1.5-2.9) for GS to 2.7 (95% CI: 1.9-3.6) for 5xSTS, while in men only the decline in GS was associated with fracture risk (HR: 3.4 [95% CI: 1.8-6.3]). Baseline performance and strength were also associated with increased fracture risk in men (HRs ranging from 1.8 (95% CI: 1.1-3.0) for QS to 2.5 (95% CI: 1.5-4.1) for TGUG, but not in women.

CONCLUSION

Rate of decline in physical performance in both genders, and baseline strength and performance in men, contributed independently to fracture risk. Sit-to-stand and GS were the tests most consistently associated with fractures. Further studies are required to determine whether muscle strength and/or performance improve the predictive accuracy of fracture prediction models.

Physical performance trajectories and mortality among nursing home residents: results of the SENIOR cohort

BACKGROUND

Previous studies have shown that older people can experience a considerable change in their physical performance (PP) over time.

OBJECTIVES

To identify PP trajectories and their association with mortality among nursing home residents who were followed up for 3 years.

DESIGN

Three-year longitudinal observational study.

SETTING

Subjects of the SENIOR cohort.

SUBJECTS

Six hundred and four nursing home residents with a mean age of 82.9 ± 9.1 years.

METHODS

Baseline characteristics and the date of death were collected from the medical records. PP was assessed annually by the short physical performance battery (SPPB) test. Multiple imputations were performed to manage the missing data. PP trajectory groups were estimated using latent growth curve analysis. Cox proportional hazard regression models were applied to examine the risk of mortality according to the PP trajectory groups.

RESULTS

Three PP trajectory groups were identified: slow decline (N = 96), moderate decline (N = 234) and fast decline (N = 274). After adjustments for potential confounding variables and the baseline SPPB scores, the residents in the fast decline and moderate decline trajectory groups had an increased risk of mortality compared to those in the slow decline trajectory group, with hazard ratio values of 1.78 (95% confidence interval [CI] = 1.34-2.26) and 1.37 (95% CI = 1.10-1.66), respectively.

CONCLUSIONS

PP trajectories provide value-added information to baseline geriatric assessments and could be used for predicting 3-year mortality among nursing home residents. It may be important to regularly monitor the SPPB score and signal an alert when a fast decline in PP is detected in older people.

Individual and joint trajectories of change in bone, lean mass and physical performance in older men

BACKGROUND

Declines in bone, muscle and physical performance are associated with adverse health outcomes in older adults. However, few studies have described concurrent age-related patterns of change in these factors. The purpose of this study was to characterize change in four properties of muscle, physical performance, and bone in a prospective cohort study of older men.

METHODS

Using repeated longitudinal data from up to four visits across 6.9 years from up to 4681 men (mean age at baseline 72.7 yrs. ±5.3) participating in the Osteoporotic Fractures in Men (MrOS) Study, we used group-based trajectory models (PROC TRAJ in SAS) to identify age-related patterns of change in four properties of muscle, physical performance, and bone: total hip bone mineral (BMD) density (g/m²) and appendicular lean mass/ht² (kg/m²), by DXA; grip strength (kg), by hand dynamometry; and walking speed (m/s), by usual walking pace over 6 m. We also described joint trajectories in all pair-wise combinations of these measures. Mean posterior probabilities of placement in each trajectory (or joint membership in latent groups) were used to assess internal reliability of the model. The number of trajectories for each individual factor was limited to three, to ensure that the pair-wise determination of joint trajectories would yield a tractable number of groups as well as model fit considerations.

RESULTS

The patterns of change identified were generally similar for all measures, with three district groups declining over time at roughly similar rates; joint trajectories revealed similar patterns with no cross-over or convergence between groups. Mean posterior probabilities for all trajectories were similar and consistently above 0.8 indicating reasonable model fit to the data.

CONCLUSIONS

Our description of trajectories of change with age in bone mineral density, grip strength, walking speed and appendicular lean mass found that groups identified by these methods appeared to have little crossover or convergence of change with age, even when considering joint trajectories of change in these factors.

Do Additional Clinical Risk Factors Improve the Performance of Fracture Risk Assessment Tool (FRAX) Among Postmenopausal Women? Findings From the Women's Health Initiative Observational Study and Clinical Trials

The ability of the fracture risk assessment tool (FRAX) to discriminate between women who do and do not experience major osteoporotic fractures (MOFs) is suboptimal. Adding common clinical risk factors may improve discrimination. We used data from the Women's Health Initiative, a prospective study of women aged 50 to 79 years at baseline (n = 99,413; n = 5722 in BMD subset) enrolled at 40 US clinical centers. The primary outcome was incident MOFs assessed annually during 10 years' follow-up. For prediction of incident MOF, we examined the area under the receiver operatic characteristic curve (AUC) and net reclassification index (NRI) of the FRAX model alone and FRAX plus additional risk factors (singly or together: type 2 diabetes mellitus, frequent falls [≥2 falls in the past year], vasomotor symptoms, self-reported physical function score [RAND 36-item Health Survey subscale), and lumbar spine BMD). For NRI calculations, high risk was defined as predicted MOF risk ≥20%. We also assessed calibration as observed MOF events/expected MOF events. The AUC value for FRAX without BMD information was 0.65 (95% CI, 0.65 to 0.66). Compared with the FRAX model (without BMD), the AUC value was not improved by the addition of vasomotor symptoms, diabetes, or frequent falls, but was minimally increased by adding physical function score (AUC 0.66, 95% CI, 0.66 to 0.67). FRAX was well-calibrated for MOF prediction. The NRI of FRAX + additional variables versus FRAX alone was 5.7% (p < 0.001) among MOF cases and -1.7% among noncases (p > 0.99). Additional variables (diabetes, frequent falls, vasomotor symptoms, physical function score, or lumbar spine BMD) did not yield meaningful improvements in NRI or discrimination of FRAX for MOFs. Future studies should assess whether tools other than FRAX provide superior discrimination for prediction of MOFs. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

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.

The association between apathy, decline in physical performance, and falls in older persons

BACKGROUND

Symptoms of apathy are common in older persons. Negative effects on physical performance and fall risk are plausible, considering the pathophysiology of apathy. However, literature is scarce.

AIM

To longitudinally assess the association between apathy and (1) decline of physical performance and (2) the number of falls in older community-dwelling persons.

METHODS

The 'B vitamins for the PRevention Of Osteoporotic Fractures' study provided data on 2919 older persons over a period of 2 years. Apathy was assessed using the Geriatric Depression Scale 3. A physical performance score (PPS) was calculated using three performance tests. Falls were registered prospectively. We calculated adjusted odds ratios (ORs), Incidence Rate Ratios (IRRs), and their 95% confidence intervals. Effect modification by age and gender was investigated. We also investigated mediation by baseline PPS for the association between apathy and the number of falls.

RESULTS

Apathy and decline of PPS were independently associated. After stratification, the effect only remained in men. Age was an effect modifier; higher ORs for decreasing age. Apathy was also independently associated with the number of falls. After stratification, women had higher IRRs than men. Age modified the association in the opposite direction: higher IRRs for increasing age. Baseline PPS was a mediator in the association.

CONCLUSION

The impact of apathy on physical performance and fall incidents varied with age and gender. Potentially, in older individuals with apathy, fall risk is preceded by a decline in physical performance. In clinical practice, identifying apathy in older persons might be useful to target mobility preserving interventions.

Knee Osteoarthritis and the Risk of Medically Treated Injurious Falls Among Older Adults: A Community-Based US Cohort Study

OBJECTIVE

The risk of falls among adults with knee osteoarthritis (OA) has been documented, yet, to our knowledge no studies have examined knee OA and the risk of medically treated injurious falls (overall and by sex), which is an outcome of substantial clinical and public health relevance.

METHODS

Using data from the Health Aging and Body Composition Knee Osteoarthritis Substudy, a community-based study of white and African American older adults, we tested associations between knee OA status and the risk of injurious falls among 734 participants with a mean ± SD age of 74.7 ± 2.9 years. Knee radiographic OA (ROA) was defined as having a Kellgren-Lawrence grade of ≥2 in at least 1 knee. Knee symptomatic ROA (sROA) was defined as having both ROA and pain symptoms in the same knee. Injurious falls were defined using a validated diagnosis code algorithm from linked Medicare fee-for-service claims. Cox regression modeling was used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs).

RESULTS

The mean ± SD follow-up time was 6.59 ± 3.12 years. Of the 734 participants, 255 (34.7%) had an incident injurious fall over the entire study period. In the multivariate model, compared with those without ROA or pain, individuals with sROA (HR 1.09 [95% CI 0.73-1.65]) did not have a significantly increased risk of injurious falls. Compared with men without ROA or pain, men with sROA (HR 2.57 [95% CI 1.12-5.91]) had a significantly higher risk of injurious falls. No associations were found for women or by injurious fall type.

CONCLUSION

Knee sROA was independently associated with an increased risk of injurious falls in older men, but not in older women.

Characteristics of Self-Reported Sleep and the Risk of Falls and Fractures: The Women's Health Initiative (WHI)

Sleep disturbances are common and may influence falls and fracture directly by influencing bone turnover and muscle strength or indirectly through high comorbidity or poor physical function. To investigate the association between self-reported sleep and falls and fractures, we prospectively studied 157,306 women in the Women's Health Initiative (WHI) using information on sleep quality, sleep duration, and insomnia from questionnaires. Annual self-report of falling two or more times (ie, "recurrent falling") during each year of follow-up was modeled with repeated measures logistic regression models fit by generalized estimating equations. Cox proportional hazards models were used to investigate sleep disturbance and time to first fracture. We examined the risks of recurrent falls and fracture by sleep duration with 7 hours as referent. We examined the risks across categories of sleep disturbance, insomnia status, and sleep quality. The average follow-up time was 7.6 years for falls and 12.0 years for fractures. In multivariable adjusted models, including adjustment for comorbidity, medications, and physical function, women who were short (≤5 hours) and long (≥10 hours) sleepers had increased odds of recurrent falls (odds ratio [OR] 1.28; 95% confidence interval [CI], 1.23 to 1.34 and OR 1.25; 95% CI, 1.09 to 1.43, respectively). Poor sleep quality, insomnia, and more sleep disturbances were also associated with an increased odds of recurrent falls. Short sleep was associated with an increased risk of all fractures, and upper limb, lower limb, and central body fractures, but not hip fractures, with hazard ratios ranging from 1.10 to 1.13 (p < 0.05). There was little association between other sleep characteristics and fracture. In conclusion, short and long sleep duration and poor sleep quality were independently associated with increased odds of recurrent falls. Short sleep was associated with modest increase in fractures. Future long-term trials of sleep interventions should include falls and fractures as endpoints. © 2018 American Society for Bone and Mineral Research.

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.

Effects of bilateral swing-away grab bars on the biomechanics of stand-to-sit and sit-to-stand toilet transfers

PURPOSE

Kinetic characteristics of transfers to and from a toilet performed using bilateral grab bars are not fully quantified to inform grab bar design and configuration. The purpose of this study was to (1) determine effects of bilateral swing-away grab bars on peaks of ankle, knee and hip joint moments during grab bar assisted stand-to-sit and sit-to-stand transfers; and (2) determine effects of three different heights and widths of swing-away grab bars on the same kinetic characteristics.

METHODS

Healthy subjects (N = 11, age 25-58 years) performed stand-to-sit and sit-to-stand transfers with and without grab bars. In transfers with grab bars, 9 grab bar configurations were tested by varying their height from the floor (0.787 m, 0.813 m, 0.838 m; 31″-33″) and width, the distance of each grab bar from the toilet's centerline (0.330 m, 0.356 m, 0.381 m; 13″-15″). Motion capture, force plate and inverse dynamics analysis were used to determine lower limb joint moments.

RESULTS

The use of bilateral grab bars generally reduced the peak magnitude of extension moments at lower limb joints during stand-to-sit and sit-to-stand transfers (p < .05), except the ankle joint moments during stand-to-sit transfers. Relatively few differences in peak joint moments were found between studied grab bar widths or heights.

CONCLUSION

The obtained results suggest that the studied ranges of grab bar configurations reduce moment demands on the leg joints and thus decrease difficulty and required lower limb muscle effort to perform the transfers. Implications for Rehabilitation Maximizing the benefits of assistive technology in the built environment requires a careful assessment of their spatial and configurational dimensions, especially in respect to the needs and abilities of the intended users. Examining the kinetic characteristics of transfers to and from a toilet using the swing-away grab bars is useful for informing grab bar design and configuration recommendations for assisted living and skilled nursing facilities. Our findings suggest that the swing-away grab bars located at certain ranges are a reasonable alternative to the grab bars mandated by the current Americans with Disabilities Act (ADA) Accessibility Guidelines. Future research investigating the effects of grab bars on transfer performance should consider additional factors, such as a wider range of abilities and transfer methods of the users.

Beyond ADA Accessibility Requirements: Meeting Seniors' Needs for Toilet Transfers

PURPOSE

To identify the optimal spatial and dimensional requirements of grab bars that support independent and assisted transfers by older adults and their care providers.

BACKGROUND

Although research has demonstrated that toilet grab bars based on the Americans with Disabilities Act (ADA) Accessibility Standards do not meet the needs of older adults, the specific dimensional requirements for alternative configurations are unknown.

METHODS

A two-phased study with older adults and care providers in residential facilities was conducted to determine the optimal requirements for grab bars. Seniors and caregivers in skilled nursing facilities performed transfers using a mock-up toilet. In Phase 1, participants evaluated three grab bar configurations to identify optimal characteristics for safety, ease of use, comfort, and helpfulness. These characteristics were then validated for using ability-matched samples in Phase 2.

RESULTS

The optimal configuration derived in Phase 1 included fold-down grab bars on both sides of the toilet (14" from centerline [CL] of toilet, 32" above the floor, and extended a minimum of 6" in front of the toilet) with one side open and a sidewall 24" from CL of toilet on the other. Phase 2 feedback was significantly positive for independent and one-person transfers and somewhat lower, albeit still positive, for two-person transfers.

CONCLUSION

The study provides substantial evidence that bilateral grab bars are significantly more effective than those that comply with current ADA Accessibility Standards. Findings provide specific spatial and dimensional attributes for grab bar configurations that would be most effective in senior facilities.

Cognitive and Physical Function in Relation to the Risk of Injurious Falls in Older Adults: A Population-Based Study

Background

We aimed to quantify the independent effect of cognitive and physical deficits on the risk of injurious falls, to verify whether this risk is modified by global cognitive impairment, and to explore whether risk varies by follow-up time.

Methods

Data on 2,495 participants (≥60 years) from the population-based Swedish National Study on Aging and Care in Kungsholmen (SNAC-K) study were analyzed using flexible parametric survival models. Two cognitive domains (processing speed and executive function) were assessed with standard tests. Physical function tests included balance (one-leg-stands), walking speed, chair stands, and grip strength. Global cognition was assessed using the Mini-Mental State Examination.

Results

A total of 167 people experienced an injurious fall over 3 years of follow-up, 310 over 5 years, and 571 over 10 years. Each standard deviation worse balance, slower walking speed, and longer chair stand time increased the risk of injurious falls over 3 years by 43%, 38%, and 23%, respectively (p < .05). Each standard deviation worse processing speed and executive function was significantly associated with 10% increased risk of injurious falls over 10 years (p < .05). In stratified analyses, deficits in physical functioning were associated with injurious falls only in people with cognitive impairment, whereas deficits in processing speed and executive function were associated with injurious falls only in people without cognitive impairment.

Conclusions

Deficits in specific cognitive domains, such as processing speed and executive function, appear to predict injurious falls in the long term. Deficits in physical function predict falls in the short term, especially in people with global cognitive impairment.

Cross-Sectional and Prospective Associations Between β-Amyloid in the Brain and Chair Rise Performance in Nondementia Older Adults With Spontaneous Memory Complaints

BACKGROUND

The objectives of this study were to examine the cross-sectional and prospective associations of muscle functional performance as assessed by a chair rise test and brain amyloid load among nondemented older adults with spontaneous memory complaints.

METHODS

This is a secondary analysis, with an observational design, using data from the MAPT randomized controlled trial. Individuals assessed for brain amyloid load (florbetapir F18 positron emission tomography) and without clinical dementia (N = 269 aged 75.2±4.2 years; 60.2% women) participated in the study. Cortical and regional standard uptake value ratios (SUVRs) were obtained. The main outcome measure was the 5-repetition chair rise performance (maximum speed-higher is better), which was assessed at baseline and at 6, 12, 24, and 36 months. Adjusted multiple linear (cross-sectional) and mixed-effect (overtime) regressions were performed.

RESULTS

Any of mean cortical (regions of interest) and each regional SUVRs (anterior cingulate, anterior putamen, caudate, hippocampus, medial orbitofrontal cortex, occipital cortex, parietal cortex, pons, posterior cingulate, posterior putamen, precuneus, semioval center, and temporal cortex) were not associated to chair rise after adjustment for multiplicity. These findings were obtained for both cross-sectional and prospective associations.

CONCLUSIONS

Brain amyloid was not found to be associated to chair rise performance in nondemented older adults with memory complaints. Potential mechanisms on the links, if any, of amyloid load with physical performance are probably not dependent on muscle function.