Usual Pace Research Articles

Predictors of walking capacity in peripheral arterial disease patients

OBJECTIVE:To estimate walking capacity in intermittent claudication patients through a prediction model based on clinical characteristics and the walking impairment questionnaire.METHODS:The sample included 133 intermittent claudication patients of both genders aged between 30 and 80 years. Data regarding clinical characteristics, the walking impairment questionnaire and treadmill walking test performance were obtained. Multiple regression modeling was conducted to predict claudication onset distance and total walking distance using clinical characteristics (age, height, mass, body mass index, ankle brachial index lower, gender, history of smoking and co-morbid conditions) and walking impairment questionnaire responses. Comparisons of claudication onset distance and total walking distance measured during treadmill tests and estimated by a regression equation were performed using paired t-tests.RESULTS:Co-morbid conditions (diabetes and coronary artery disease) and questions related to difficulty in walking short distances (walking indoors – such as around your house and walking 5 blocks) and at low speed (walking 1 block at average speed – usual pace) resulted in the development of new prediction models high significant for claudication onset distance and total walking distance (p<0.001). In addition, non-significant differences from the results obtained by the treadmill test and estimated by the current model (p>0.05) were observed.CONCLUSION:The current study demonstrated that walking capacity can be adequately estimated based on co-morbid conditions and responses to the walking impairment questionnaire.

Assessing the Temporal Relationship Between Cognition and Gait: Slow Gait Predicts Cognitive Decline in the Mayo Clinic Study of Aging

The association between gait speed and cognition has been reported; however, there is limited knowledge about the temporal associations between gait slowing and cognitive decline among cognitively normal individuals. The Mayo Clinic Study of Aging is a population-based study of Olmsted County, Minnesota, United States, residents aged 70-89 years. This analysis included 1,478 cognitively normal participants who were evaluated every 15 months with a nurse visit, neurologic evaluation, and neuropsychological testing. The neuropsychological battery used nine tests to compute domain-specific (memory, language, executive function, and visuospatial skills) and global cognitive z-scores. Timed gait speed (m/s) was assessed over 25 feet (7.6 meters) at a usual pace. Using mixed models, we examined baseline gait speed (continuous and in quartiles) as a predictor of cognitive decline and baseline cognition as a predictor of gait speed changes controlling for demographics and medical conditions. Cross-sectionally, faster gait speed was associated with better performance in memory, executive function, and global cognition. Both cognitive scores and gait speed declined over time. A faster gait speed at baseline was associated with less cognitive decline across all domain-specific and global scores. These results were slightly attenuated after excluding persons with incident mild cognitive impairment or dementia. By contrast, baseline cognition was not associated with changes in gait speed. Our study suggests that slow gait precedes cognitive decline. Gait speed may be useful as a reliable, easily attainable, and noninvasive risk factor for cognitive decline.

Sarcopenia and cognitive impairment in elderly women: results from the EPIDOS cohort

common pathophysiological pathways are shared between age-related body composition changes and cognitive impairment. evaluate whether current operative sarcopenia definitions are associated with cognition in community-dwelling older women. cross-sectional analyses. a total of 3,025 women aged 75 years and older. body composition (assessed by dual energy X-ray absorptiometry) and cognition (measured by short portable mental status questionnaire) were obtained in all participants. Multivariate logistic regression models assessed the association of six operative definitions of sarcopenia with cognitive impairment. Gait speed (GS, measured over a 6-meter track at usual pace) and handgrip strength (HG, measured by a hand-held dynamometer) were considered additional factors of interest. a total of 492 (16.3%) women were cognitively impaired. The prevalence of sarcopenia ranged from 3.3 to 18.8%. No sarcopenia definition was associated with cognitive impairment after controlling for potential confounders. To proof consistency, the analyses were performed using GS and HG, two well-established predictors of cognitive impairment. Low GS [odds ratio (OR) 2.42, 95% confidence interval (CI) 1.72-3.40] and low HG (OR: 1.81, 95% CI: 1.33-2.46) were associated with cognitive impairment. no significant association was evidenced between different operative sarcopenia definitions and cognitive impairment. The study suggests that the association between physical performance and cognitive impairment in not mediated by sarcopenia.

Increasing Cytotechnologist Workload Above 100 Slides per Day Using the BD FocalPoint GS Imaging System Negatively Affects Screening Performance

Studies examining the effects of increased workload on the performance of individual cytotechnologists are limited. Using FocalPoint GS, the performance of 3 cytotechnologists was evaluated. The study consisted of 3 phases. In phase I, cytotechnologists were asked to screen at their usual pace. In phase II, cytotechnologists were asked to screen as fast as possible without feeling that the quality of their work was diminished. In phase III, cytotechnologists were asked to screen at least 15% more than their daily workload from phase II. Productivity was increased by decreasing the percentage of cases that underwent full manual review (from 38% to 19%) and by decreasing the time spent on each slide (from 5.5 min to 3.7 min). Overall, the total abnormal rate decreased by 31.9% from phase I to phase III of the study. In addition, the false-negative fraction increased significantly, from 1% to 6.9%. Our results indicated a negative association between increased cytotechnologist daily workload with FocalPoint GS and CT screening performance. Workloads were increased by decreasing the time spent reviewing 10 fields of view and the percentage of cases that underwent full manual review.

Gait Speed as a Measure in Geriatric Assessment in Clinical Settings: A Systematic Review

Gait speed is a quick, inexpensive, reliable measure of functional capacity with well-documented predictive value for major health-related outcomes. Numerous epidemiological studies have documented gait speed in healthy, community-dwelling older people. The purpose of this study is to undertake a systematic review and meta-analysis of gait speed in a specific group with mobility limitations-geriatric patients in clinical settings. Relevant databases were searched systematically for original research articles published in February 2011 measuring gait speed in persons aged 70 or older in hospital inpatient or outpatients settings. Meta-analysis determined gait speed data for each setting adjusting for covariates. The review included 48 studies providing data from 7,000 participants. Across the hospital settings, the gait speed estimate for usual pace was 0.58 m/s (95% confidence interval [CI]: 0.49-0.67) and for maximal pace was 0.89 m/s (95% CI: 0.75-1.02). These estimates were based on most recent year of publication (2011) and median percentage of female participants (63%). Gait speed at usual pace in acute care settings was 0.46 m/s (95% CI: 0.34-0.57), which was significantly slower than the gait speed of 0.74 m/s (95% CI: 0.65-0.83) recorded in outpatient settings. Gait speed is an important measure in comprehensive geriatric assessment. The consolidation of data from multiple studies reported in this meta-analysis highlights the mobility limitations experienced by older people in clinical settings and the need for ongoing rehabilitation to attain levels sufficient for reintegration in the community.

Vitamin D status and functional performance in peripheral artery disease

The clinical implications of low vitamin D in peripheral artery disease (PAD) are unknown. We hypothesized that among individuals with PAD, lower levels of 25-hydroxyvitamin D would be associated with poorer functional performance, more adverse calf muscle characteristics, and poorer peripheral nerve function. Participants were 402 men and women with PAD who underwent measurement of 25-hydroxyvitamin D (DiaSorin radioimmunoassay) along with 6-minute walk testing, measurement of walking velocity at usual and fastest pace, computed tomography-measured calf muscle density, and peripheral nerve conduction velocity (NCV). Among PAD participants, 20.4% had 25-hydroxyvitamin D levels < 30 nmol/L, consistent with deficient vitamin D status. Adjusting for age, sex, and race, lower 25-hydroxyvitamin D levels were associated with poorer 6-minute walk performance (p trend = 0.002), slower usual-paced 4-meter walking velocity (p trend = 0.031), slower fast-paced 4-meter walking velocity (p trend = 0.043), and lower calf muscle density (p trend = 0.031). After additional adjustment for body mass index (BMI) and diabetes, none of these associations remained statistically significant. However, lower levels of 25-hydroxyvitamin D were associated with poorer peroneal NCV (p trend = 0.013) and poorer sural NCV (p trend = 0.039), even after adjusting for age, sex, race, BMI, comorbidities, smoking, physical activity, and other confounders. In conclusion, vitamin D deficiency is common among people with PAD encountered in clinical settings. After adjusting for BMI and diabetes mellitus, we found no significant associations of lower levels of 25-hydroxyvitamin D with poorer functional performance or calf muscle characteristics. Associations of low vitamin D levels with poorer peripheral nerve function require further study.

Non-exchangeability of running vs. other exercise in their association with adiposity, and its implications for public health recommendations.

PurposeCurrent physical activity recommendations assume that different activities can be exchanged to produce the same weight-control benefits so long as total energy expended remains the same (exchangeability premise). To this end, they recommend calculating energy expenditure as the product of the time spent performing each activity and the activity's metabolic equivalents (MET), which may be summed to achieve target levels. The validity of the exchangeability premise was assessed using data from the National Runners' Health Study.MethodsPhysical activity dose was compared to body mass index (BMI) and body circumferences in 33,374 runners who reported usual distance run and pace, and usual times spent running and other exercises per week. MET hours per day (METhr/d) from running was computed from: a) time and intensity, and b) reported distance run (1.02 MET•hours per km).ResultsWhen computed from time and intensity, the declines (slope±SE) per METhr/d were significantly greater (P<10−15) for running than non-running exercise for BMI (slopes±SE, male: −0.12±0.00 vs. 0.00±0.00; female: −0.12±0.00 vs. −0.01±0.01 kg/m2 per METhr/d) and waist circumference (male: −0.28±0.01 vs. −0.07±0.01; female: −0. 31±0.01 vs. −0.05±0.01 cm per METhr/d). Reported METhr/d of running was 38% to 43% greater when calculated from time and intensity than distance. Moreover, the declines per METhr/d run were significantly greater when estimated from reported distance for BMI (males: −0.29±0.01; females: −0.27±0.01 kg/m2 per METhr/d) and waist circumference (males: −0.67±0.02; females: −0.69±0.02 cm per METhr/d) than when computed from time and intensity (cited above).ConclusionThe exchangeability premise was not supported for running vs. non-running exercise. Moreover, distance-based running prescriptions may provide better weight control than time-based prescriptions for running or other activities. Additional longitudinal studies and randomized clinical trials are required to verify these results prospectively.

Prevalence of symptomatic lumbar spinal stenosis and its association with physical performance in a population-based cohort in Japan: the Wakayama Spine Study

The purpose of this study was to investigate the prevalence of symptomatic lumbar spinal stenosis (LSS) and to clarify the association between symptomatic LSS and physical performance using magnetic resonance imaging (MRI) in a population-based cohort. This cross-sectional study was performed as a part of the research on osteoarthritis/osteoporosis against disability (ROAD) in Japan and 1,009 subjects (335 men, 674 women, mean age 66.3 years, age range 21-97 years) were analyzed. An experienced orthopedic surgeon obtained the medical history and performed the physical testing for all participants. Symptomatic LSS diagnostic criteria required the presence of both symptoms and radiographic LSS findings. A 6-m walking time, chair standing time, and one-leg standing time were obtained from all participants. The prevalence of symptomatic LSS was 9.3% (95% confidence interval [CI]: 7.7-11.3) overall, 10.1% (CI: 7.4-13.8) in men and 8.9% (CI: 7.0-11.3) in women. There was a difference in the prevalence with increasing age by gender. The LSS prevalence showed little difference with age greater than 70 years for men, but the LSS prevalence for women was higher with increasing age. Among physical performance measures, 6-m walking time at a maximal pace was significantly associated with symptomatic LSS (P = 0.03). The prevalence of symptomatic LSS was approximately 10% in a cohort resembling the general Japanese population. A 6-m walking time at a maximal pace was a more sensitive index than walking at a usual pace in assessing decreased physical performance associated with symptomatic LSS.

Influencia del tapiz rodante sobre la variabilidad de la marcha en sujetos jóvenes y sanos

ObjectiveThe aim of study was to analyze the differences in gait variability (stride interval time series) in two different conditions (spontaneous walking vs. treadmill walking) in healthy and active young subjects. MethodThe stride interval time series derived from ten healthy and active males were studied in three experimental conditions: a) walking on level ground at their self-determined usual paces around open circle circuit for 25 minutes; and b) walking on a treadmill for 25 minutes at the same pace as in Situation a. A capture device enabled stride interval time series to be collected directly and stored during walking in both conditions, using a simple electronic push-button mounted in the heel of the dominant foot support of an insole placed in the running shoe. The mean and standard deviation (SD), Approximate Entropy (ApEn), Sample Entropy (SampEn) and Multiscale Entropy (MSE) were calculated. ResultsDE, ApEn and SampEn showed no significant changes between both experimental conditions. All MSE significantly decreased from the spontaneous walking to treadmill walking. ConclusionsThere was a loss of complexity signal when subjects walked on a treadmill. This should be taken into account for future studies under these conditions.

Low-grade chronic inflammation and superoxide anion production by NADPH oxidase are the main determinants of physical frailty in older adults

Background. Physical performance measured by gait speed is being recognized as a major instrument for clinical evaluation in older adults, because it predicts physical frailty, loss of autonomy, hospitalization and decreased survival. Low-grade chronic inflammation and oxidative stress, mediated partly by the superoxide anion produced by NADPH oxidase, are closely linked and could be involved in age-related physical decline. Objective. To determine whether slow gait speed is associated with superoxide anion overproduction by NADPH oxidase and low-grade chronic inflammation. Design and setting. Observational study among the 280 elderly of an ambulatory geriatric care unit (191 women, 89 men, 79.9 ± 6.1 years old). Methods. Gait speed was evaluated by walking at self-chosen usual pace. Usual gait speed < 0.8 m/s was defined as slow gait speed. Superoxide anion production was evaluated using a lucigenin-based chemiluminescence method. Inflammation was evaluated by CRP, fibrinogen and leukocyte count. Results. Among the 280 participants, 179 (63.9%) walked with a gait speed < 0.8 m/s (slow walkers) and 101 (36.1%) with a gait speed ≥ 0.8 m/s. Superoxide production and inflammation markers, such as fibrinogen, were more important in slow walkers (p = 0.004 and p = 0.006, respectively). In multivariate analysis, superoxide anion overproduction and fibrinogen were independently associated with physical frailty assessed by slow gait speed (p = 0.028 and p = 0.007, respectively). Conclusion. Physical frailty in older people is associated with superoxide anion overproduction by NADPH oxidase and low-grade chronic inflammation.

Nonlinear Analysis of Human Gait Signals

Nonlinear dynamics has been introduced to the analysis of biological data and increasingly recognized to be functionally relevant. The aim of this study is to evaluate nonlinear and chaotic dynamics of gait signals. For this purpose, we analyzed gait data in ten healthy subjects who walked for an hour at their usual, slow and fast paces. Poincare plots, Hurst Exponents and the Lyapunov Exponents of gait signals were calculated. The results show that the Hurst Exponents are significantly increased during slow and fast paces. For all subjects, the Lyapunov Exponents are increased during normal gait, which indicates that signals are more chaotic. This can be due to decreased nonlinear interaction of variables in slow and fast paces. The finite values of Hurst Exponents and positive values of Lyapunov Exponents suggest that all of gait signals have low dimensional chaos. In addition, the complexity of signals is decreased during slow and fast gait. Results are useful for the early diagnosis of common gait pathologies.

CSM 2012 Orthopaedic Section Platform Presentations (Abstracts OPL1–OPL64)

CSM 2012 Orthopaedic Section Platform Presentations (Abstracts OPL1–OPL64)

Reference values for hand grip strength, muscle mass, walking time, and one-leg standing time as indices for locomotive syndrome and associated disability: the second survey of the ROAD study

BackgroundWe established reference values for hand grip strength, muscle mass, walking time, and one-leg standing time as indices reflecting components of locomotive syndrome and associated disability using a large-scale population-based sample from the second survey of the Research on Osteoarthritis/Osteoporosis Against Disability (ROAD) cohort. MethodsWe measured the above-mentioned indices in 2,468 individuals ≥40 years old (826 men, 1,642 women; mean age 71.8 years) during the second visit of the ROAD study. Disability was defined as certified disability according to the long-term care insurance system through public health centres of each municipality. ResultsMean values for hand grip strength (weaker side), muscle mass of the thighs, walking time for 6m at the usual pace, and the fastest pace for men were 32.7 kg, 7.0 kg, 5.6 s, and 3.7 s, respectively, and those for women were 20.8 kg, 5.2 kg, 5.9 s, and 4.1s, respectively. The median values for one-leg standing time (weaker side) were 14s for men and 12s for women. The prevalence of disability in men aged 65–69, 70–74, 75–79, and ≥80 was 0.0, 1.0, 6.3, and 8.8%, respectively, and in women was 3.4, 3.5, 9.2, and 14.7%, respectively. There were significant associations between the presence of disability and walking time for 6m at the usual pace and at the fastest pace, and between the presence of disability and walking speed. ConclusionsWe established reference values for indices reflecting components of locomotive syndrome, and identified significant associations between walking ability and disability.

Self-reported estimation of usual walking speed improves the performance of questionnaires estimating walking capacity in patients with vascular-type claudication

Most questionnaires do not estimate the usual walking speed of the patient, although it is well known that patients may experience apparently different walking capacities if walking slow or fast. We hypothesized that correcting the self-reported estimated walking capacity by a coefficient issued from the self-reported estimation of usual walking speed would significantly improve the correlation between questionnaire-estimated and treadmill-measured walking capacity. Three hundred ten consecutive patients complaining of vascular-type claudication were asked to estimate their usual walking speed in comparison to people of their age (or friends or relatives) with ratings ranging from much slower (1 pt) to much faster (5 pts), in addition to the filling out of the walking impairment questionnaire (WIQ) and the estimated ambulatory capacity by history questionnaire (EACH-Q). Corrected WIQ (WIQc) and corrected EACH-Q (EACH-Qc) scores were obtained by multiplying the scores of each questionnaire by the "usual-speed" coefficient and dividing by 5. Results for questionnaire scores were compared to maximal walking time (MWT) on a treadmill. All but four patients self-completed the usual-speed question. Median scores (25-75 centiles) were 41% (26-59) for the WIQ and 24% (11-41) for the EACH-Q. Coefficients of correlation of the three WIQ subscales and of the EACH-Q with treadmill results were significantly improved after correction by the "usual-speed" question. Overall, WIQ (mean of the three WIQ subscales) tended to improve but did not reach significance. Correcting the self-reported estimation of walking capacity by a self-reported estimation of usual walking pace significantly improves the correlation of all WIQ subscale scores and of the EACH-Q score with treadmill measurements of capacity. This confirms the interest of speed estimation in patients with peripheral arterial occlusive disease and claudication.

Gait Speed, Body Composition, and Dementia. The EPIDOS-Toulouse Cohort

Slow gait speed (GS) predicts dementia, but this association might be mediated by body composition parameters like total fat mass (TFM) or total lean mass (TLM). The aim of the study was to evaluate whether GS, TLM, and TFM were associated factors with an increased risk for subsequent dementia in community-dwelling older women. A case-control study was nested in the EPIDemiologie de l'OStéoporose cohort. GS (at usual pace more than 6 m), TLM, and TFM (assessed by dual energy x-ray absorptiometry) were measured at baseline. Cognitive performance was evaluated at baseline and at 7 years of follow-up. The presence of dementia was assured by two blinded memory experts based on best practice and validated criteria. Multivariate logistic regression models assessed the association of GS, TLM, and TFM with dementia risk. Of the initial 1,462 women, 75 years old and older, 647 (43.4%) were cognitively intact at baseline and had a full cognitive assessment at 7 years (145 of them developed dementia). Controlled for covariates (demographics, physical activity, self-reported disabilities, and comorbidities), GS was an independent associated factor for subsequent dementia as a continuous variable (odds ratio [OR] 2.28, 95% CI: 1.32-3.94) and as a categorized variable (OR 2.38, 95% CI: 1.28-4.43 highest vs lowest quartile). Neither interaction with GS nor a statistically significant association with dementia risk was found for TLM and TFM. GS was an independent associated factor for subsequent dementia not mediated by TLM or TFM.

Superficial Femoral Artery Plaque and Functional Performance in Peripheral Arterial Disease: Walking and Leg Circulation Study (WALCS III)

We studied associations of magnetic resonance imaging measurements of plaque area and relative percent lumen reduction in the proximal superficial femoral artery with functional performance among participants with peripheral arterial disease. The clinical significance of directly imaged plaque characteristics in lower extremity arteries is not well established. A total of 454 participants with an ankle brachial index <1.00 underwent magnetic resonance cross-sectional imaging of the proximal superficial femoral artery and completed a 6-min walk test, measurement of 4-m walking velocity at usual and fastest pace, and measurement of physical activity with a vertical accelerometer. Adjusting for age, sex, race, body mass index, smoking, statin use, comorbidities, and other covariates, higher mean plaque area (1st quintile [least plaque]: 394 m, 2nd quintile: 360 m, 3rd quintile: 359 m, 4th quintile: 329 m, 5th quintile [greatest plaque]: 311 m; p trend <0.001) and smaller mean percent lumen area (1st quintile [greatest plaque]: 319 m, 2nd quintile: 330 m, 3rd quintile: 364 m, 4th quintile: 350 m, 5th quintile: 390 m; p trend <0.001) were associated with shorter distance achieved in the 6-min walk test. Greater mean plaque area was also associated with slower usual-paced walking velocity (p trend = 0.006) and slower fastest-paced 4-m walking velocity (p trend = 0.003). Associations of mean plaque area and mean lumen area with 6-min walk distance remained statistically significant even after additional adjustment for the ankle brachial index and leg symptoms. Among participants with peripheral arterial disease, greater plaque burden and smaller lumen area in the proximal superficial femoral artery are associated independently with poorer functional performance, even after adjusting for the ankle brachial index and leg symptoms.

Poorer clock draw test scores are associated with greater functional impairment in peripheral artery disease: The Walking and Leg Circulation Study II

We hypothesized that, in the absence of clinically recognized dementia, cognitive dysfunction measured by the clock draw test (CDT) is associated with greater functional impairment in men and women with peripheral artery disease (PAD). Participants were men and women aged 60 years and older with Mini-Mental Status Examination scores ≥ 24 with PAD (n = 335) and without PAD (n = 234). We evaluated the 6-minute walk test, 4-meter walking velocity at usual and fastest pace, the Short Physical Performance Battery (SPPB), and accelerometer-measured physical activity. CDTs were scored using the Shulman system as follows: Category 1 (worst): CDT score 0-2; Category 2: CDT score 3; Category 3 (best): CDT score 4-5. Results were adjusted for age, sex, race, education, ankle-brachial index (ABI), and comorbidities. In individuals with PAD, lower CDT scores were associated with slower 4-meter usual-paced walking velocity (Category 1: 0.78 meters/second; Category 2: 0.83 meters/second; Category 3: 0.86 meters/second; p-trend = 0.025) and lower physical activity (Category 1: 420 activity units; Category 2: 677 activity units; Category 3: 701 activity units; p-trend = 0.045). Poorer CDT scores were also associated with worse functional performance in individuals without PAD (usual and fast-paced walking velocity and SPPB, p-trend = 0.022, 0.043, and 0.031, respectively). In conclusion, cognitive impairment identified with CDT is independently associated with greater functional impairment in older, dementia-free individuals with and without PAD. Longitudinal studies are necessary to explore whether baseline CDT scores and changes in CDT scores over time can predict long-term decline in functional performance in individuals with and without PAD.

Reference values for the Timed Up and Go test in healthy Japanese elderly people: Determination using the methodology of meta‐analysis

The purpose of this study was to determine the reference value for the Timed Up and Go test (TUG) in healthy Japanese elderly people using the methodology of meta-analysis, and to determine the value for different measurement protocols. Relevant research articles were identified from electronic databases: MEDLINE, Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Igaku-cyuouzasshi. The search was conducted from January 1991 to June 2010, and the terms "timed up and go" and "elderly" were used in combination in the search. Furthermore, the searches were limited to articles involving Japanese healthy elderly people aged 60years and older. Weighted means of TUG were calculated by a fixed effect model and a random effect model to estimate reference values. Furthermore, the 95% confidence interval (CI) for the weighted mean of TUG was also estimated. Twelve studies fulfilled the inclusion criteria: eight provided data for maximum effort, and five provided data related to usual pace. When weighted means of TUG were estimated by the fixed effect model, there was significant heterogeneity. Therefore, a random effect model was used for re-estimation. As a result, the weighted mean of TUG with maximum effort was 6.60s (95% CI=6.18-7.02s), and that at usual pace was 8.86s (95% CI=7.99-9.72s). The reference values of TUG in Japanese healthy elderly people calculated in this study are certainly shorter than in African-Americans and Caucasians. The reference values of TUG estimated by our study appear to be specific for healthy, elderly, Japanese people.

Comparison Of Aerobic To Resistance Exercise In Older Breast Cancer Survivors: Preliminary Findings From A One-year RCT

Exercise may be particularly important for older breast cancer survivors (BCS) because of the combined impact of treatment plus aging on their physical health; however, studies specific to older BCS are lacking. PURPOSE: The purpose of this study was to compare the relative benefits of aerobic exercise and resistance exercise on physical functioning and body size in inactive, older (aged 65+) BCS who had completed primary treatment. METHODS: Early-stage, older BCS (mean age: 73 yrs) who were at least 2 years past radiation and/or chemotherapy were randomized to one year of strength training (STR), aerobic training (AER) or a control program of flexibility training (FLEX). Data from BCS who completed baseline, 6 and 12 month testing were used for preliminary analysis (STR: n=30, AER: n=29; FLEX: n=25). Primary outcomes were lower and upper body strength measured by 1-RM leg press (LPmax) and bench press (BPmax); time to rise from a chair 5 times (Chair); time to walk 4m at an usual pace (UW; m/s); distance walked in 6 min (6MW); and body weight. Separate 3 × 3 repeated measures ANOVAs were used to determine significant main effects of time and group × time interactions for each primary outcome. RESULTS: There were significant main effects for all outcome measures, except for weight, where improvements occurred over time for all groups (Table 1). There were no significant group x time interactions for any measure. CONCLUSIONS: These preliminary findings suggest that one year of exercise training, independent of exercise mode, may improve physical function in older BCS. However, it remains possible that observed changes simply represent population changes over time or a learning effect on effort-dependent tests. Supported by NIH grant R01 CA120123Table 1: Percent improvement in physical function and body weight after one year of exercise training in older BCS.

Seniors' Walking Speed May Predict Life Expectancy

Gait speed correlated with expected years of life remaining to people aged 65 years and older, according to a report in JAMA. For both sexes and at any age older than 65 years, a gait speed of 0.8 meters per second correlated with the median life expectancy of a person, given his or her age and sex. Faster walking speeds consistently correlated with extended survival, said Dr. Stephanie Studenski of the division of geriatric medicine at the University of Pittsburgh and her associates. They assessed the relationship between gait speed and survival in a pooled analysis using data from nine cohort studies of community-dwelling adults. Each study included at least 400 people, gait speed data at baseline, and follow-up for at least 5 years. All of the studies measured gait speed by having subjects walk at their usual pace from a standing start for 6–8 feet indoors. There were 34,485 study subjects, including “substantial” numbers of African American and Hispanic patients, as well as 1,765 who were older than 85 years. Follow-up ranged from 6 to 21 years, with a median of 14 years. Gait speed ranged widely, from less than 0.4 meters per second (in 1,247 people) to more than 1.4 meters per second (in 1,491 people). There were 17,528 deaths during follow-up. Predicted years of life remaining correlated with gait speed for patients of both sexes and all ages. A walking speed of approximately 0.8 meters per second was associated with the predicted median life expectancy for a subject's age and sex. Gait speeds faster than that rate predicted longer-than-average life expectancy, while slower gait speeds predicted shorter-than-average life expectancy. Gait speeds of 1.2 meters per second and faster predicted “exceptional” life expectancy, the investigators reported (JAMA 2010;305:50-8). Gait speed “was especially informative after age 75 years” in patients who had no, or only minor, functional limitations. It may be less helpful in predicting life expectancy for patients who already report functional impairments and dependency on others for performing the activities of daily living, the investigators noted. The data allowed Dr. Studenski and her colleagues to calculate survival estimates for a broad range of gait speeds, and to calculate absolute rates and median years of survival. “Compared with prior studies that were too small to assess potential effect modification by age, sex, race/ethnicity, and other subgroups, we were able to assess multiple subgroup effects with substantial power,” the researchers said. However, they emphasized that the survival estimates must be validated in additional data sets before being used in clinical practice. “Because gait speed can be assessed by nonprofessional staff using a 4-meter walkway and a stopwatch, it is relatively simple to measure compared with many medical assessments,” they added. In practice, gait speed can be used to identify elderly patients with a high probability of living 5–10 more years, who can then be targeted for preventive interventions that require a long time before benefits are realized. It can also identify patients at increased risk for early mortality, who can then be targeted for interventions to maximize health and survival, the researchers explained. If gait speed is tracked over time, it can serve as an indicator that new health problems have arisen. It can also be helpful in stratifying risks from surgery or chemotherapy, the investigators said. The data also suggested that there may be a subpopulation of older adults “who walk very slowly but survive for long periods. It would be valuable to further characterize this subgroup,” Dr. Studenski and her associates said. In an editorial accompanying the article, Matteo Cesari, MD, PhD, of Università Campus Bio-Medico, Rome, said that gait speed may become a new “vital sign” that is specifically sensitive in older patients (JAMA 2010;305:93-4). The usefulness of assessing gait speed is obvious for geriatricians and primary care physicians, but other specialists may also find it helpful, he said. Dr. Cesari pointed out that gait-speed testing is inexpensive, objective, easy to interpret, and easy to adopt into clinical practice. The study was supported by the National Institute on Aging and by Merck. Dr. Studenski also received support from Merck, Novartis, and GTX, and royalties from “Hazzard's Geriatric Medicine & Gerontology,” Sixth Edition, (McGraw Hill, 2009). Mary Ann Moon is a freelance writer based in Clarksburg, Md.