Lower-extremity function in persons over the age of 70 years as a predictor of subsequent disability

Emotional well-being predicts subsequent functional independence and survival

OBJECTIVE

To determine whether positive affect has an independent effect on functional status, mobility, and survival in an older Mexican American sample.

DESIGN

A 2-year prospective cohort study.

SETTING

Five Southwestern states: Texas, California, Arizona, New Mexico, and Colorado.

PARTICIPANTS

A population-based sample of 2282 Mexican Americans aged 65 to 99 who reported no functional limitations at baseline interview.

MEASUREMENTS

In-home interviews in 1993-1994 and again in 1995-1996 assessed demographic variables, health conditions, activities of daily living, performance-based mobility, survival, and a rating of positive and negative affect.

RESULTS

In multivariate analyses, there was a direct relationship between positive affect scores at baseline and mobility, functional status, and survival 2 years later, controlling for functional status, sociodemographic variables, major chronic conditions, body mass index (BMI), smoking status, drinking status, and negative affect at baseline. Subjects with high positive affect were half as likely (odds ratio (OR) = 0.48; 95% confidence interval (CI) 0.29, 0.93) to become disabled in activities of daily living (ADLs), two-thirds as likely (OR = 0.64; 95% CI 0.51, 0.79) to have a slow walking speed, and half as likely (OR 0.53; 95% CI 0.30, 0.93) to have died during the 2-year follow-up compared to those with lower positive affect scores.

CONCLUSIONS

Our results support the concept that positive affect, or emotional well-being, is different from the absence of depression or negative affect. Positive affect seems to protect individuals against physical declines in old age.

Factors that modify the association between knee pain and mobility limitation in older women: the Women's Health and Aging Study

OBJECTIVE

To investigate the influence of pain severity, knee extensor muscle weakness, obesity, depression, and activity on the association between recent knee pain and limitation of usual and fast paced walking, and ability to rise from a chair.

METHODS

A cross sectional analysis of 769 older women (mean age 77.8, range 65-101) with physical disability, but no severe cognitive impairment. Severity of knee pain in the past month was classified as none, moderate, or severe. Mobility was measured using timed performance tests.

RESULTS

The prevalence of recent knee pain was 53% (408/769). One third of the women with pain reported it to be severe. In general, knee pain was only significantly associated with limited mobility if severe. Obesity, activity and, to a lesser extent, depression intensified the effects of pain. Knee extensor weakness did not. Obesity was a distinctive risk factor in that it substantially increased the risk of mobility limitation, but only in women with pain. In women who had severe pain, activity (walking more than three city blocks in the past week) increased the risk of walking disability more than inactivity. Depression had a minor, but statistically significant effect on walking ability, but not the ability to rise from a chair.

CONCLUSION

In older women with recent knee pain, a high pain severity score, obesity, and activity are important factors that increase the risk of mobility limitation.

Mobility difficulties and physical activity as predictors of mortality and loss of independence in the community-living older population

OBJECTIVE

In older people, mobility impairments and physical inactivity are risk factors for further disability and death. We studied the interaction of physical activity and mobility impairment as a predictor of dependence and mortality.

DESIGN

A population-based, prospective study. The data were collected in structured interviews in the year 1988 and 8 years later in the year 1996 as part of the Evergreen Project.

PARTICIPANTS

Subjects were 1109 independently living, at baseline 65- to 84-year-old people in the city of Jyvaskyla, in central Finland.

METHODS

Participants were ranked into four groups: (1) Intact mobility and physically active (Mobile-Active), (2) Intact mobility and sedentary (Mobile-Sedentary), (3) Impaired mobility and physically active (Impaired-Active), and (4) Impaired mobility and sedentary (Impaired-Sedentary). The confounders adjusted for in the models included age, marital status, education, chronic conditions, smoking, and physical exercise earlier in life.

RESULTS

In men and women, the relative risk of death was two times greater in Impaired-Active and three times greater in Impaired-Sedentary groups than the risk of death in Mobile-Active groups. However, the risk of death did not differ between Mobile-Active and Mobile-Sedentary groups. The odds ratio for dependency (95% confidence interval) in Impaired-Sedentary men was 5.21 (1.44-18.70) and in Impaired-Sedentary women was 2.92 (1.52-5.60) compared to Mobile-Active groups. The risk of dependence did not differ significantly between Mobile-Active, Mobile-Sedentary, and Impaired-Active groups.

CONCLUSIONS

Mobility impairments predicted mortality and dependence. However, among people with impaired mobility, physical activity was associated with lower risks, whereas the risk did not differ according to activity level among those with intact mobility. Despite of their overall greater risk, mobility-impaired people may be able to prevent further disability and mortality by physical exercise.

Chair and bed rise performance in ADL-impaired congregate housing residents

OBJECTIVES

To examine the ability of activity of daily living (ADL)-impaired older adults to successfully rise, and, when successful, the time taken to rise, from a bed and chair under varying rise task demands.

SETTING

Seven congregate housing facilities

SUBJECTS

Congregate housing residents (n = 116, mean age 82) who admitted to requiring assistance (such as from a person, equipment, or device) in performing at least one of the following mobility-related ADLs: transferring, walking, bathing, and toileting.

METHODS

Subjects performed a series of bed and chair rise tasks where the rise task demand varied according to the head of bed (HOB) height, chair seat height, and use of hands. Bed rise tasks included supine to sit-to-edge, sit up in bed with hand use, and sit up in bed without hands, all performed from a bed where the HOB was adjusted to 0, 30, and 45 degrees elevations; roll to side-lying then rise (HOB 0 degrees); and supine to stand (HOB 0 degrees). Chair seat heights were adjusted according to the percent of the distance between the floor and the knee (% FK), and included rises (1) with hands and then without hands at 140, 120, 100, and 80% FK; (2) from a reclining (105 degrees at chair back) and tilting (seat tilted 10 degrees posteriorly) chair (100% FK); and (3) from a 80% FK seat height with a 4-inch cushion added, with and then without hands. Logistic regression for repeated measures was used to test for differences between tasks in the ability to rise. After log transformation of rise time, a linear effects model was used to compare rise time between tasks.

RESULTS

The median total number of tasks successfully completed was 18 (range, 3-21). Nearly all subjects were able to rise from positions where the starting surface was elevated as long as hand use was unlimited. With the HOB at 30 or 45 degrees essentially all subjects could complete supine to sit-to-edge and sit up with hands. Essentially all subjects could rise from a seat height at 140, 120, and 100% FK as long as hand use was allowed. A small group (8-10%) of subjects was dependent upon hand use to perform the least challenging tasks, such as 140% FK without hands chair rise and 45 degrees sit up without hands. This dependency upon hand use increased significantly as the demand of the task increased, that is, as the HOB or seat height was lowered. Approximately three-quarters of the sample could not rise from a flat (0 degrees HOB elevation) bed or low (80% FK) chair when hand use was not allowed. Similar trends were seen in rise performance time, that is, performance times tended to increase as the HOB or chair seat elevation declined and as hand use was limited. Total self-reported ADL disability, compared to the single ADL transferring item, was a stronger predictor of rise ability and timed rise performance, particularly for chair rise tasks.

CONCLUSIONS

Lowering HOB height and seat height increased bed and chair rise task difficulty, particularly when hand use was restricted. Restricting hand use in low HOB height or lowered seat height conditions may help to identify older adults with declining rise ability. Yet, many of those who could not rise under "without hands" conditions could rise under "with hands" conditions, suggesting that dependency on hand use may be a marker of progressive rise impairment but may not predict day-to-day natural milieu rise performance. Intertask differences in performance time may be statistically significant but are clinically small. Given the relationship between self-reported ADL disability and rise performance, impaired rise performance may be considered a marker for ADL disability. These bed and chair rise tasks can serve as outcomes for an intervention to improve bed and chair rise ability and might also be used in future studies to quantify improvements or declines in function over time, to refine physical therapy protocols, and to examine the effect of bed and chair design modifications on bed and chai

Lower extremity function and subsequent disability: consistency across studies, predictive models, and value of gait speed alone compared with the short physical performance battery

BACKGROUND

Although it has been demonstrated that physical performance measures predict incident disability in previously nondisabled older persons, the available data have not been fully developed to create usable methods for determining risk profiles in community-dwelling populations. Using several populations and different follow-up periods, this study replicates previous findings by using the Established Populations for the Epidemiologic Study of the Elderly (EPESE) performance battery and provides equations for the prediction of disability risk according to age, sex, and level of performance.

METHODS

Tests of balance, time to walk 8 ft, and time to rise from a chair 5 times were administered to 4,588 initially nondisabled persons in the four sites of the EPESE and to 1,946 initially nondisabled persons in the Hispanic EPESE. Follow-up assessment for activity of daily living (ADL) and mobility-related disability occurred from 1 to 6 years later.

RESULTS

In the EPESE, compared with those with the best performance (EPESE summary performance score of 10-12), the relative risks of mobility-related disability for those with scores of 4-6 ranged from 2.9 to 4.9 and the relative risk of disability for those with scores of 7-9 ranged from 1.5 to 2.1, with similar consistent results for ADL disability. The observed rates of incident disability according to performance level in the Hispanic EPESE agreed closely with rates predicted from models developed from the EPESE sites. Receiver operating characteristic curves showed that gait speed alone performed almost as well as the full battery in predicting incident disability.

CONCLUSIONS

Performance tests of lower extremity function accurately predict disability across diverse populations. Equations derived from models using both the summary score and the gait speed alone allow for the estimation of risk of disability in community-dwelling populations and provide valuable information for estimating sample size for clinical trials of disability prevention.

Asymptomatic peripheral arterial disease is independently associated with impaired lower extremity functioning: the women's health and aging study

BACKGROUND

We report the implications of asymptomatic lower extremity peripheral arterial disease (PAD) for lower extremity functioning among participants in the Women's Health and Aging Study, an observational study of disabled women > or = 65 years of age living in and around Baltimore.

METHODS AND RESULTS

The ankle brachial index (ABI) and measures of upper and lower extremity functioning were measured among study participants. Of 933 women with ABI < or =1. 50, 328 (31%) [corrected] had an ABI <0.90, consistent with PAD. Sixty-three percent of PAD participants had no exertional leg pain. Among participants without exertional leg pain, lower ABI levels were associated with slower walking velocity, poorer standing balance score, slower time to arise 5 times consecutively from a seated position, and fewer blocks walked per week, adjusting for age, sex, race, cigarette smoking, and comorbidities. ABI was not associated independently with measures of upper extremity functioning.

CONCLUSIONS

Asymptomatic PAD is common and is independently associated with impaired lower extremity functioning. In addition to preventing cardiovascular morbidity and death, further study is warranted to identify effective interventions to improve functioning among the growing number of men and women with asymptomatic PAD.

Functional performance and exercise of older adults in long-term care settings

Performing functional activities and exercising are important for older adults living in long-term care settings. Participation in these activities not only improves and maintains function in older adults but also can improve physical and emotional health and quality of life. The purpose of this study was to explore the variables that influence functional performance and exercise activity in a group of nursing home residents. Participants included 59 residents in a long-term care facility. The mean age of participants was 88 +/- 6.9, and the majority were women (76%), White (97%), and unmarried (76%). Residents participated in a single face-to-face interview. Chart reviews for demographic and health information also were performed. Based on stepwise multiple regression analyses, upper and lower extremity contractures and cognitive status were the only variables that significantly influenced functional performance and accounted for 49% of the variance in function. Self-efficacy and outcome expectations were the only variables to significantly influence exercise behavior and accounted for 57% of the variance in this behavior. These findings can be used to help develop and implement effective restorative nursing care programs in long-term care settings.

A randomized trial of weighted vest use in ambulatory older adults: strength, performance, and quality of life outcomes

BACKGROUND

Lower extremity weakness is a major risk factor for falls and hip fractures. Aging muscle is capable of responding to strengthening techniques. Strategies for providing accessible, inexpensive, safe, and effective strengthening programs for older adults are needed.

OBJECTIVE

To evaluate whether use of a weighted vest improved strength, physical performance, markers of bone turnover, or health-related quality of life.

DESIGN

A 27-week randomized, controlled, unmasked clinical trial. The primary outcome was peak isokinetic knee extensor strength at follow-up, adjusted for baseline strength.

SETTING

Home-based program.

PARTICIPANTS

A total of 62 women and men, mean age 74 years.

INTERVENTIONS

Subjects were randomized to: no vest (n = 21), 3% body weight (BW) vest (n = 19), or 5% BW vest (n = 22). The vest is a nylon garment with pockets that are loaded with adjustable weights. The vest was prescribed for 2 hours daily, 4 days per week. No specific physical activities were mandated.

MEASUREMENTS

All measures were made at baseline and 27 weeks. These included: knee strength and endurance by isokinetic dynamometer; timed physical performance tests; serum osteocalcin and urinary N-telopeptides; and health-related quality of life scales.

RESULTS

Follow-up values of muscular strength and endurance, physical performance, bone turnover markers, and health-related quality of life did not differ by treatment assignment. The final study visit was attended by 19 (90%), 15 (80%), and 20 (91%) of the control, 3%, and 5% groups, respectively. Three permanent discontinuations of vest use occurred.

CONCLUSIONS

Weighted vest use did not result in improvement in multiple domains of strength and function and did not affect bone turnover markers. We conclude that the training stimulus afforded by the vest (at the dosage tested) was below the required amount to produce strength gains or bone stimulation.

Understanding what motivates older adults to exercise

The purposes of this study were to explore the factors that influenced adherence to an exercise program for older adults, and compare differences in motivation, efficacy expectations, health status, age, functional performance, and falls between adherers and nonadherers. A combined qualitative and quantitative design was used. Participants included 23 of the 24 members of an existing walking group, with an average age of 81 +/- 7.2 years. Fourteen (60%) participants did not adhere to walking, while 9 (40%) adhered. Those that adhered had fewer functional limitations due to their health, (F = 7.7, p < .05), better functional performance (F = 4.0, p < .05), stronger self-efficacy expectations related to exercise (F = 4.3, p < .05), and fewer falls (F = 4.4, p < .05). Six major themes were identified that impacted adherence: a) beliefs about exercise; b) benefits of exercise; c) past experiences with exercise; d) goals; e) personality; and f) unpleasant sensations associated with exercise. Interventions that focus on teaching older adults about the benefits of exercise, establishing appropriate goals, and decreasing unpleasant and increasing pleasant sensations associated with exercise may be useful to improve adherence to a regular exercise program.

Determinants of exercise tolerance after acute myocardial infarction in older persons

OBJECTIVES

Exercise tolerance is reduced with advancing age. Identification of potentially reversible determinants of the age-related decrement in exercise tolerance, which remain largely unexplored in older subjects and in patients recovering from a recent myocardial infarction (MI), may have useful therapeutic implications. The objective of this study was to identify the independent determinants of exercise tolerance in older patients with a recent MI.

DESIGN, SETTING, AND PARTICIPANTS

Data is from baseline assessment of 265 post-MI patients (age range 45-85 years) enrolled in the Cardiac Rehabilitation in Advanced Age randomized, controlled trial. Patients with major comorbidities or severe MI complications were excluded from the trial. Exercise tolerance was determined from symptom-limited exercise testing and expressed as total work capacity (TWC, kg.m) or peak oxygen consumption (VO2peak, mL/kg/min). The associations between both TWC and VO2peak and baseline demographic, social, clinical, and neuropsychological variables and an index of health-related quality of life were determined with univariate and multivariate analysis.

RESULTS

With univariate analysis, TWC decreased by 1285 kg.m per decade of increasing age between 45 and 85 years of age. With multivariate analysis, TWC decreased by 922 kg.m per decade. Increasing age (P < .001), female gender (P < .001), a small body surface area (P < .001), a low level of usual physical exercise before MI (P < .002), and the presence of post-MI depressive symptoms (P < .024) were independently associated with a lower TWC. The same factors, in addition to a small arm muscle area (P < .002), were also independently associated with a lower VO2peak.

CONCLUSIONS

Age per se accounts for approximately 70% of the age-related decay in TWC or VO2peak. However, the inclusion of modifiable factors such as physical exercise and depression in the prediction model reinforces the importance of a multidimensional approach to the evaluation and treatment of older patients with a recent MI.

Balance, mobility, and falls among elderly African American women

OBJECTIVE

To compare balance, mobility, recent falls, and injuries among elderly African American and white women.

DESIGN

This was a nonexperimental study. Participants, who were older than 65 yr of age, able to walk at least 30 ft, not residing in a nursing home, and with no acute medical problems, were recruited from 17 senior citizens' community centers.

RESULTS

Compared with white women (n=180), African American women (n = 118) took fewer medications, had greater body mass indexes, had less muscle strength, and had more medical conditions and neurologic abnormalities. Additionally, these women were less active and had poorer performances on an obstacle course. The two groups had a similar histories of falls and injuries. For both groups, activity level and neurologic findings were predictors of obstacle course performance. For white women, muscle strength was an additional predictor of obstacle course performance. An additional predictor for African American women was range of motion.

CONCLUSION

The poorer balance and mobility of African American women compared with white women may have consequences such as their functional dependence, resulting in their greater use of hospitals and formal and informal health services.

Functional status and walking ability after lower extremity bypass grafting or angioplasty for intermittent claudication: results from a prospective outcomes study

OBJECTIVE

The purpose of this study was the prospective comparison of functional outcomes after lower extremity bypass grafting surgery, angioplasty, or medical management of intermittent claudication.

METHODS

The study was designed as a prospective cohort study to compare functional outcomes for patients with interventional management to medical management, including a matched (younger, with more disability) subgroup, followed for a mean of 19 months. Sixteen Chicago-area vascular surgery clinics participated in the study. The subjects were consecutively enrolled patients with an abnormal ankle-brachial blood pressure index (ABI), without signs of rest pain, ulcer, or gangrene, and without prior lower extremity revascularization procedures. The main outcome measures were changes in physical functioning, community walking distance, bodily pain, leg symptoms, and ABI.

RESULTS

Of the 526 study patients, 20% underwent revascularization procedures (60 surgical bypass grafting and 44 angioplasty only). The mean ABI improved significantly for the patients who underwent bypass grafting surgery (0.20; P <.001) and modestly for the patients who underwent angioplasty (0.09; P <. 05). Patients undergoing bypass grafting and angioplasty maintained highly significant (P <.001) improvements in mean physical functioning, (17%, 14%), bodily pain (18%, 13%), and walking distance (28%, 27%) scores and reported greater leg symptom improvement. The results were far superior for the patients with greater improvement in ABI. The conditions of the 277 unmatched patients who underwent medical management declined on all outcome measures, and the conditions of the 145 matched patients who underwent medical management improved 5% (P <.001) on walking distance score. Eighteen percent of the study patients failed to complete the full study follow-up period.

CONCLUSION

Most of the functional improvement achieved by patients who underwent interventional management appears to be related to improved patency rather than to selection bias or placebo effects. The functional gains were approximately half those often reported for patients for hip arthroplasty and similar to patients who undergo elective coronary angioplasty.

Screening for mobility disorders by the Mobility Control subscale of the short version of the Sickness Impact Profile

OBJECTIVE

To test the usefulness of the Mobility Control subscale (MC scale) of the short version of the Sickness Impact Profile (SIP68) as a simple self-administered questionnaire for screening mobility disorders in a population of independent living elderly.

DESIGN

The SIP68-MC scale was compared with the results of one functional test as independent criteria.

SUBJECTS AND SETTING

A group of 81 people of 70 years and older was selected from a potential population of over 200 people. All were independent living elderly persons selected from a general practice.

INTERVENTIONS

The short version of the Sickness Impact Profile and questions about falling last year were applied. Three functional tests were carried out: walking 10 metres, get up and sit down in a chair five times and a test for standing balance. A trained observer rated all tests.

RESULTS

It is shown that the sensitivity of the MC scale (cut-off point: 1) with the total functional score is 91%, with a relative low specificity (59%). The relationship between the SIP-MC score and falling frequency is significant when there is a falling frequency equal to or more than two times a year.

CONCLUSION

It is concluded that the MC scale is a useful test for screening mobility disorders in the elderly.

The power of ageism on physical function of older persons: reversibility of age-related gait changes

OBJECTIVE

To test the hypothesis that age-associated changes in physical function, particularly walking performance, are influenced by ageism and that the activation of positive sterotypes of aging can partially reverse these changes.

DESIGN

Randomized intervention study.

SETTING

General community.

PARTICIPANTS

Forty-seven community-dwelling men and women (63-82 years old) who walked independently and described themselves as healthy.

INTERVENTION

Thirty-minute exposure to the subconscious reinforcement of either a positive or negative stereotype of aging while subjects played a computer game.

MEASUREMENTS

Pre- and postintervention measures of gait speed and percent swing time (the time spent with one foot in the air during walking). Health and psychosocial status were also evaluated.

RESULTS

Significant increases in walking speed (9%+/-2%; P < .001) and percent swing time (percent change: 1.1%+/-0.4%; P = .023) were observed in subjects who received reinforcement of positive stereotypes of aging. Gait speed and swing time did not change in those who received reinforcement of negative stereotypes of aging. The observed improvements in gait were related to the positive intervention, but were not related to age, gender, health status, or psychosocial status.

CONCLUSIONS

Stereotypes of aging apparently have a powerful impact on the gait of older persons. Interventions designed to enhance perceptions of old age may prove beneficial in helping to improve gait and functional independence among older persons. In the future, positive changes in society's view of aging may also help to reduce and prevent age-related declines in function and the associated deleterious consequences.

Walking speed and stride length predicts 36 months dependency, mortality, and institutionalization in Chinese aged 70 and older

BACKGROUND

Increasing emphasis is being placed on physical performance measures as an outcome predictor. It is uncertain whether one or two simple measurements will have predictive value compared with a battery of tests.

OBJECTIVES

To assess whether simple performance measures such as walking speed and stride length will predict dependency, mortality, and institutionalization.

DESIGN

A 3-year longitudinal study of a random sample of subjects.

SETTING

Older people living in the community in Hong Kong, Special Administrative Region, China.

SUBJECTS

A total of 2032 Chinese subjects aged 70 years and older were recruited territory-wide by proportional random sampling and followed for 3 years.

MEASUREMENTS

Functional status was measured using the Barthel Index at baseline and follow-up. The time taken to walk a distance of 16 feet and the number of steps taken were measured at baseline. Stride length is estimated by dividing 16 by the average number of steps needed to complete the walk. Outcomes regarding dependency, mortality, and institutionalization at 36 months were recorded.

RESULTS

After excluding subjects lost to follow-up and those who had died, data were available for 559 men and 612 women. Univariate analysis showed that reduced walking speed and stride length were associated with increased risk of dependency, mortality, and institutionalization. In multivariate analysis for dependency and mortality, stride length, walking speed, age, and sex were included in the best prediction model (ROC = 0.798 and 0.707, respectively), whereas only stride length was included in the prediction for institutionalization (ROC = 0.764).

CONCLUSIONS

In terms of prevention or modifying outcomes, these two simple performance measures may be used as indicators for checking for occult disease and for interventional measures such as exercise prescription.

Physical activity and nutrition in older adults

Physical activity and nutrient intake are important determinants of health throughout life. Many of the alterations in physiological structure and function that occur with age may result from disuse and disability as well as from diets deficient in energy, protein or other specific nutrients. Although a healthy diet can provide significant health benefits, diet alone, is not sufficient to provide optimal health, nor protect us from the hazards of sedentary habits. Nor is physical activity alone. The ideal combines sufficient exercise and a healthy diet.

Oral administration of the growth hormone secretagogue MK-677 increases markers of bone turnover in healthy and functionally impaired elderly adults. The MK-677 Study Group

Growth hormone (GH) stimulates osteoblasts in vitro and increases bone turnover and stimulates osteoblast activity when given to elderly subjects. Probably a major effect of GH on bone is mediated through stimulation of either circulating or locally produced insulin-like growth factor I (IGF-I). We determined the effect of chronic administration of the GH secretagogue, MK-677, on serum IGF-I and markers of bone turnover in 187 elderly adults (65 years or older) enrolled in three randomized, double-blind, placebo-controlled clinical studies lasting 2-9 weeks. Urine was collected for determination of N-telopeptide cross-links (NTXs), a marker of bone resorption, and blood was collected for determination of serum osteocalcin and bone-specific alkaline phosphatase (BSAP), as bone formation markers, and serum IGF-I levels pre- and post-treatment. Dose response data were initially obtained in healthy elderly subjects who received oral doses of 10 mg or 25 mg of MK-677 or placebo for 2 weeks (n = 10-12/group). Treatment with 10 mg and 25 mg of MK-677 for 2 weeks increased mean urine NTXs 10% and 17%, respectively (p < 0.05 vs. placebo). Additionally, 50 healthy elderly subjects received either placebo (n = 20) for 4 weeks or 25 mg of MK-677 (n = 30) daily for 2 weeks followed by 50 mg daily for 2 weeks. MK-677 increased mean serum osteocalcin by 8% (p < 0.05 vs. placebo). In both studies, MK-677 increased serum IGF-I levels significantly (55-94%). Subsequently, the biological effects of MK-677 were studied in 105 elderly subjects who met objective criteria for functional impairment. Subjects were randomized to receive oral doses of placebo for 9 weeks or either 5, 10, or 25 mg of MK-677 daily for an initial 2 weeks followed by 25 mg of MK-677 daily for the next 7 weeks(n = 63 on MK-677 and n = 28 on placebo completed 9 weeks of therapy). Treatment with MK-677 (all MK-677 groups combined) for 9 weeks increased mean serum osteocalcin by 29.4% and BSAP by 10.4% (p < 0.001 vs. placebo) and mean urinary NTX excretion by 22.6% (p < 0.05 vs. placebo). The change from baseline serum osteocalcin correlated with the change from baseline serum IGF-I in the MK-677 group (r = 0.37; p < 0.01). In conclusion, once daily dosing with MK-677, an orally active GH secretagogue, stimulates bone turnover in elderly subjects based on elevations in biochemical markers of bone resorption and formation.

Heart failure in community-dwelling older persons: aims, design and adherence rate of the ICARe Dicomano project: an epidemiologic study. Insufficienza Cardiaca negli Anziani Residenti a Dicomano

BACKGROUND

The prevalence of heart failure (HF) increases with age, and HF is a major cause of disability and mortality in older persons. Detection of HF in epidemiological studies has relied on criteria validated only in young and middle-age adults, and, therefore, may prove inadequate in older subjects, because they do not take into account the pathophysiologic and clinical peculiarities of HF in old age. Thus, the true prevalence of HF in the older general population remains uncertain and has probably been underestimated in previous studies. Moreover, the mechanism and the extent by which HF hinders physical functioning in older people has not been fully elucidated.

OBJECTIVES

This paper describes the design of the ICARe study, carried out in an older home-dwelling population to collect data about: (1) the sensitivity and specificity of diagnostic criteria used previously in epidemiological studies of HF; (2) the prevalence of the different pathophysiologic forms of HF; and (3) the impact of HF on overall health status, and on physical functioning, in the absence or presence of chronic comorbidity.

DESIGN AND SETTING

This was a cross-sectional survey. Eligible were all community-dwelling persons aged 65 years or older recorded in the Registry Office of Dicomano, a small town nearby Florence (Italy). All the domains of multidimensional geriatric assessment were explored through different phases of the study (home interview, laboratory testing, geriatric visit) that comprised an extensive cardiopulmonary instrumental assessment including: color Doppler echocardiography, echotomography of the carotid arteries used in an original method to determine arterial compliance, and bell spirometry. Presence of major chronic conditions was ascertained by predefined, standard algorithms that were based largely on clinical examination.

RESULTS

There were 864 older persons eligible for the ICARe study. Even with a substantial decline from home interview (91.2%) to the cardiopulmonary study (71.1%), the adherence rate remained high throughout the study, and the population examined was fairly representative of the original eligible population. Thus, we believe that the data collected in this study offer a unique opportunity to assess the validity of the diagnostic clinical criteria for HF in the general older population, to identify the pathophysiology underlying the syndrome, and to investigate the relationship between HF, comorbidity, and disability.

A 30-s chair-stand test as a measure of lower body strength in community-residing older adults

Measuring lower body strength is critical in evaluating the functional performance of older adults. The purpose of this study was to assess the test-retest reliability and the criterion-related and construct validity of a 30-s chair stand as a measure of lower body strength in adults over the age of 60 years. Seventy-six community-dwelling older adults (M age = 70.5 years) volunteered to participate in the study, which involved performing two 30-s chair-stand tests and two maximum leg-press tests, each conducted on separate days 2-5 days apart. Test-retest intraclass correlations of .84 for men and .92 for women, utilizing one-way analysis of variance procedures appropriate for a single trial, together with a nonsignificant change in scores from Day 1 testing to Day 2, indicate that the 30-s chair stand has good stability reliability. A moderately high correlation between chair-stand performance and maximum weight-adjusted leg-press performance for both men and women (r = .78 and .71, respectively) supports the criterion-related validity of the chair stand as a measure of lower body strength. Construct (or discriminant) validity of the chair stand was demonstrated by the test's ability to detect differences between various age and physical activity level groups. As expected, chair-stand performance decreased significantly across age groups in decades--from the 60s to the 70s to the 80s (p < .01) and was significantly lower for low-active participants than for high-active participants (p < .0001). It was concluded that the 30-s chair stand provides a reasonably reliable and valid indicator of lower body strength in generally active, community-dwelling older adults.

Activities of daily living. Old-fashioned or still useful?

1 The Index of Activities of Daily Living (ADL) is used by many nurses to assess function in older adults, but there is debate regarding the scoring, wording of questions, and validity in diverse populations. 2 Older adults may give inaccurate answers to ADL questions because they misunderstand the questions, have personal reasons for underreporting or overreporting difficulty in ADL, or fail to recognize difficulty because they have adapted to changes in function. 3 Physical performance tests, especially of the lower extremities, may be an alternative method of assessing function, especially in high-functioning older adults who report no difficulty in ADL.

A population-based study of environmental hazards in the homes of older persons

OBJECTIVES

This study sought to estimate the population-based prevalence of environmental hazards in the homes of older persons and to determine whether the prevalence of these hazards differs by housing type or by level of disability in terms of activities of daily living (ADLs).

METHODS

An environmental assessment was completed in the homes of 1000 persons 72 years and older. Weighted prevalence rates were calculated for each of the potential hazards and subsequently compared among subgroups of participants characterized by housing type and level of ADL disability.

RESULTS

Overall, the prevalence of most environmental hazards was high. Two or more hazards were found in 59% of bathrooms and in 23% to 42% of the other rooms. Nearly all homes had at least 2 potential hazards. Although age-restricted housing was less hazardous than community housing, older persons who were disabled were no less likely to be exposed to environmental hazards than older persons who were nondisabled.

CONCLUSIONS

Environmental hazards are common in the homes of community-living older persons.

Risk factors for lack of recovery of ADL independence after hospital discharge

OBJECTIVE

To determine risk factors for lack of recovery of independent functioning after hospitalization for acute medical illness.

DESIGN

Secondary analysis of cohort study of patients receiving home nursing after discharge.

SETTING

Evaluations performed in the home after discharge and 1 month later.

PARTICIPANTS

A total of 73 adults aged 65 years and older who were independent in activities of daily living (ADLs) before hospitalization and dependent at discharge.

MEASUREMENTS

Self-report and objective measures of function, mobility, and cognition.

OUTCOME

Return to independence in ADLs 1 month after discharge.

RESULTS

Fifty-nine percent of patients did not return to previous ADL independence by 1 month postdischarge. The likelihood for not recovering was 87% (95% CI, 70-100%) if a patient had a Mini-Mental State Examination score (MMSE) < 24 at discharge (P = .015). Among patients with good cognition, 85% (95% CI, 66-100%) of those who used an assistive device indoors before hospitalization did not recover (P = .007). Among patients with good cognition and no previous assistive device use, 73% (95% CI, 47-99%) of those with a Timed "Up and Go" of > or = 40 seconds did not recover (P = .012). The likelihood of recovery was high (76%, 95% CI 56-96%) if a patient had no assistive device prehospital, a good MMSE, and a Timed "Up and Go" of < 20 seconds.

CONCLUSION

We hypothesize that a classification strategy using cognition, prehospital mobility, and discharge physical performance will predict patients who are less likely to recover functional independence after hospitalization. If this is validated in future study, it may help clinicians identify patients who are more likely to benefit from additional intervention.

Bioimpedance analysis: potential for measuring lower limb skeletal muscle mass

BACKGROUND

Ambulation, balance, and lower extremity bone mass and strength are all partially dependent on lower limb skeletal muscle mass. At present, both research and clinical methods of evaluating lower limb skeletal muscle mass as a component of nutrition assessment are limited. One potential simple and inexpensive method is lower extremity bioimpedance analysis (BIA). The present study had two objectives: to examine the determinants of lower limb resistance, with the underlying hypothesis that fluid-containing muscle is the main electrical conductor of the lower limbs; and to establish if a correlation of equivalent magnitude and similar covariates is observed when height squared (H2) is used instead of lower limb length squared (L2) in multiple regression models relating resistance to independent variables.

METHODS

Lower limb resistance was measured using a contact-electrode BIA system, and lower limb fat and skeletal muscle were estimated by dual-energy x-ray absorptiometry in healthy adults. A physical BIA model was developed in the form of a regression equation with path-length (as L2 and H2)-adjusted resistance as dependent variables and lower limb skeletal muscle, fat, age, and gender as potential independent variables.

RESULTS

There were 94 subjects, 34 men and 60 women, with a mean (-/+SD) age of 41.5+/-17.8 years. Strong associations were observed between L2/resistance and lower limb skeletal muscle, although for both men and women, age entered into the model as a significant covariate (total R2, men = .79 and women = .72; both p < .001). Similar models were observed with H2/resistance as dependent variable. Additional analyses showed a significantly lower resistance in lower limb skeletal muscle and height-matched old vs young subjects.

CONCLUSIONS

Strong associations exist between measured lower limb resistance and lower limb muscle mass, adjusting for electrical path length either by L2 or H2. These observations suggest the potential of predicting skeletal muscle using BIA-measured lower limb resistance adjusted for stature. Age is also an independent variable in lower limb resistance-skeletal muscle associations, suggesting the need to establish underlying mechanisms of age-related resistance effects and to consider subject age when developing BIA prediction models.

Disability in older adults. 1: Prevalence, causes, and consequences

The effects of disability on an aging population's health and welfare are an important issue in gerontological research. The rapid growth of the elderly population and increases in longevity have led to an ongoing debate about whether longer lives can be matched by longer active lives that are free from disability. After a detailed review of current disability literature, the authors discuss the impact of disability in the elderly, defining disability and reviewing three classes of disability--physical, mental, and social. Both subjective and objective disability measures are described, and disability trends and prevalence rates are reviewed and compared cross culturally, by gender, by age, and over time. The path from chronic disease to disability is described and the consequences of living with disability are discussed in terms of family burdens and the increased need for medical care.

Risk factors for functional status decline in community-living elderly people: a systematic literature review

To lay the groundwork for devising, improving and implementing strategies to prevent or delay the onset of disability in the elderly, we conducted a systematic literature review of longitudinal studies published between 1985 and 1997 that reported statistical associations between individual base-line risk factors and subsequent functional status in community-living older persons. Functional status decline was defined as disability or physical function limitation. We used MEDLINE, PSYCINFO, SOCA, EMBASE, bibliographies and expert consultation to select the articles, 78 of which met the selection criteria. Risk factors were categorized into 14 domains and coded by two independent abstractors. Based on the methodological quality of the statistical analyses between risk factors and functional outcomes (e.g. control for base-line functional status, control for confounding, attrition rate), the strength of evidence was derived for each risk factor. The association of functional decline with medical findings was also analyzed. The highest strength of evidence for an increased risk in functional status decline was found for (alphabetical order) cognitive impairment, depression, disease burden (comorbidity), increased and decreased body mass index, lower extremity functional limitation, low frequency of social contacts, low level of physical activity, no alcohol use compared to moderate use, poor self-perceived health, smoking and vision impairment. The review revealed that some risk factors (e.g. nutrition, physical environment) have been neglected in past research. This review will help investigators set priorities for future research of the Disablement Process, plan health and social services for elderly persons and develop more cost-effective programs for preventing disability among them.

Home-based leg strengthening for older adults initiated through private practice

BACKGROUND

Leg strength correlates with functional ability in the frail elderly, many of whom can be reached through a private practice setting. The purpose of this study was to demonstrate the feasibility of physician-prescribed, home-based, clinic-monitored, high-intensity leg-strengthening treatment among elderly patients with a variety of medical problems.

METHODS

Twenty-two elderly patients with a variety of chronic medical conditions were invited to participate during regularly scheduled office visits if they had difficulty rising from a chair and an unsteady, cautious gait (age 85.1 +/- 5.7, 14 female). Physical therapists (PT) instructed patients to lift ankle weights at home, three times per week. Patients visited PT five times over a 12-week period. Weights were increased at each visit.

RESULTS

Patients' one-repetition maximum increased (right leg 13 to 21 lb, P = 0.00; left leg 15 to 22 lb, P = 0.00). Patients also improved in habitual (18 to 12 s, P = 0.01) and tandem (38 to 26 s, P = 0.00) 20-foot walking times and sit-to-stand time (5 to 3 s, P = 0.01).

CONCLUSION

The primary care physician can initiate a home-based leg-strengthening program that is practical for and well tolerated by the frail elderly.

Disability, physical activity, and muscle strength in older women: the Women's Health and Aging Study

OBJECTIVE

To study associations of motor disability, physical activity, and muscle strength in older women, in particular to investigate whether model of spiraling decrease is expressed in the data.

DESIGN

Cross-sectional analysis using data from the baseline measurements of The Women's Health and Aging Study (WHAS).

SETTING

Participants' homes.

PARTICIPANTS

A total of 1,002 disabled women aged 65 years and older living in the community.

OUTCOME MEASURES

Motor disability was measured by the number of self-reported difficulties in grasping, lifting 101b, walking across a small room, walking 1/4 mile, climbing 10 steps, and doing heavy housework. Level of physical activity was determined from response to a series of questions on the frequency and amount of common activities and physical exercise. Hand grip and knee extension forces were measured using portable hand-held dynamometers.

RESULTS

Disability and physical activity were inversely associated, with inactivity being most common among the most disabled women. Those with poorer strength reported more difficulties in motor activities. Greater strength was found among the physically more active. In stratified analyses, the positive association of physical activity on knee extension strength was consistent across disability levels. Multiple regression analysis showed that both physical activity and muscle strength were significant predictors for severity of disability. Structural equation model (LISREL) showed that muscle strength had a mediating role between physical activity and disability; disability was associated with physical inactivity, which correlated with lower muscle strength, which was associated with greater degree of disability.

CONCLUSION

Even though causality cannot be confirmed in this cross-sectional analysis, our findings suggested a spiraling model of decline in which muscle strength has a significant role.

Does laxity alter the relationship between strength and physical function in knee osteoarthritis?

OBJECTIVE

Since strengthening interventions have had a lower-than-expected impact on patient function in studies of knee osteoarthritis (OA) and it is known that laxity influences muscle activity, this study examined whether the relationship between strength and function is weaker in the presence of laxity.

METHODS

One hundred sixty-four patients with knee OA were studied. Knee OA was defined by the presence of definite osteophytes, and patients had to have at least a little difficulty with knee-requiring activities. Tests were performed to determine quadriceps and hamstring strength, varus-valgus laxity, functional status (Western Ontario and McMaster Universities Osteoarthritis Index Physical Functioning subscale [WOMAC-PF] and chair-stand performance), body mass index, and pain. High and low laxity groups were defined as above and below the sample median, respectively.

RESULTS

Strength and chair-stand rates correlated (r = 0.44 to 0.52), as did strength and the WOMAC-PF score (r = -0.21 to -0.36). In multivariate analyses, greater laxity was consistently associated with a weaker relationship between strength (quadriceps or hamstring) and physical functioning (chair-stand rate or WOMAC-PF score).

CONCLUSION

Varus-valgus laxity is associated with a decrease in the magnitude of the relationship between strength and physical function in knee OA. In studies examining the functional and structural consequences of resistance exercise in knee OA, stratification of analyses by varus-valgus laxity should be considered. The effect of strengthening interventions in knee OA may be enhanced by consideration of the status of the passive restraint system.

Justification of intervention for limb-threatening ischemia: a surgical decision analysis

Intervention for vascular occlusive disease of the distal lower extremity in elderly patients will inevitably be scrutinized as medical resources decline. The authors applied surgical decision analysis to three treatment options: revascularization, amputation and expectant management. The appropriate outcome probabilities were derived from our experience with revascularization to the tibial and pedal vessels, and utility scores were obtained by formalized patient assessment. Revascularization was predicted to improve patient outcome by 1.10 quality-adjusted life-years compared with primary amputation and by 1.16 quality-adjusted life-years compared with expectant management. To gain one additional quality-adjusted life-years, revascularization would cost $5280 more than expectant management, but $33,900 less than primary amputation. Sensitivity analysis predicted revascularization to be the least costly treatment per quality-adjusted life-years as long as 1-month patency exceeds 11%. Revascularization for limb-threatening ischemia of the distal lower extremity is justified and can be performed at a reasonable cost.

Measurement of walking endurance and walking velocity with questionnaire: validation of the walking impairment questionnaire in men and women with peripheral arterial disease

OBJECTIVES

The Walking Impairment Questionnaire (WIQ) was designed to measure community walking ability in patients with peripheral arterial disease (PAD) and intermittent claudication. We compared the WIQ scores to objective measures of walking in a heterogeneous group of patients with and without PAD.

METHODS

The study was designed as a cross-sectional study, with the setting in an academic medical center. The subjects were patients with PAD (n = 145) who were identified from a noninvasive vascular laboratory at an academic medical center. The patients without PAD (n = 65) were identified from a general medicine practice. The average number of comorbidities was 2.03 for patients with PAD and 1.52 for patients without PAD. Among the patients with PAD, 28% had classical intermittent claudication symptoms and 55% had exertional leg symptoms other than claudication. The main outcome measures were the WIQ estimates of the patient-reported walking distance and walking speed on a scale of 0 to 100. Walking endurance was measured objectively with the 6-minute walk. Walking velocity was measured with a 4-m walk. PAD and PAD severity were defined with the ankle brachial index.

RESULTS

The Spearman rank correlation coefficients (rho) between the WIQ distance score and the 6-minute walk score were 0.557 among patients with PAD (P <.001) and 0.484 among patients without PAD (P <.001). The correlation coefficients between the WIQ speed score and the usual-paced 4-m walk score were 0.528 among patients with PAD (P <.001) and 0.524 among patients without PAD (P <.001). The correlations were not affected by the presence versus the absence of intermittent claudication, by PAD severity, or by the presence of 2 or more versus less than 2 comorbid illnesses. The WIQ scores in the highest and lowest quartiles were the most closely associated with the objective measures of function.

CONCLUSION

The WIQ is a valid measure of community walking ability in a heterogeneous group of patients with and without PAD. The WIQ discriminates best among patients in the highest and the lowest quartiles of walking speed and endurance.

Aging and the adrenal cortex

Aging in humans is accompanied by an increase in adrenal glucocorticoid secretion and a decline in adrenal androgen synthesis and secretion. The intense interest in adrenal function in aging individuals in recent years is in large measure related to the potential impact of cortisol excess in the development of cognitive impairment and hippocampal neuronal loss, and to the desire to provide hormone replacement and healthy aging. Although the preliminary data is tantalizing, solid scientific evidence are not at hand. It is apparent that both issues are extremely complex. Dehydroepiandrosterone (DHEA) and its 3 beta-sulfate are fascinating molecules, including their synthesis and actions in the brain. Recent studies have shown that DHEA-sulfate (DHEA-S), but not DHEA, activates peroxisome proliferator-activated receptor alpha (PPAR alpha) in the liver, an intracellular receptor belonging to the steroid receptor superfamily. Thus, DHEA-S may serve as a physiological modulator of liver fatty acid metabolism and peroxisomal enzyme expression, and thereby may contribute to the anticarcinogenic and chemoprotective properties of this intriguing class of endogenous steroids. The life-sustaining role of adrenal cortisol secretion and its regulation of metabolism via catabolic actions may be modulated by its partner DHEA and DHEA-S. During the anabolic growth period (childhood and early adulthood) the body is exposed to relatively high levels of DHEA/DHEA-S but to relatively or absolutely high levels of cortisol during infancy and the aging phase. The cortisol/DHEA-S ratio during the life span follows a U-shape curve, which may be telling us to explore these two critical adrenal steroids in tandem.

The ankle brachial index independently predicts walking velocity and walking endurance in peripheral arterial disease

OBJECTIVES

Maintaining function among older men and women is an important public health goal as the population lives longer with chronic disease. We report the relationships between lower extremity peripheral arterial disease (PAD), PAD severity, and PAD-related symptoms with walking velocity and endurance among men and women aged 55 and older.

DESIGN

A cross-sectional design.

SETTING

An academic medical center.

PARTICIPANTS

Participants with PAD were men and women aged 55 and older identified from a blood flow laboratory or a general medicine practice (n = 158). Randomly selected controls without PAD were identified from the general medicine practice (n = 70).

MEASUREMENTS

PAD was diagnosed and quantified using the ankle brachial index (ABI). Subjects were categorized according to whether they had severe PAD (ABI <0.40), mild to moderate PAD (ABI 0.40 to <0.90), or no PAD (ABI 0.90 to <1.50). Walking endurance was assessed with the 6-minute walk. Usual walking velocity and maximal walking velocity were assessed with "usual" and "maximal" paced 4-meter walks, respectively.

RESULTS

Average distances achieved in the 6-minute walk were 1569+/-390 feet for subjects with ABI 0.90-1.50, 1192+/-368 feet for subjects with ABI 0.40 to <0.90, and 942+/-334 feet for subjects with ABI < 0.40 (trend P value < .001). Walking velocities for both the usual and maximal paced 4-meter walks were slowest among subjects with ABI < 0.40 and fastest among subjects with ABI 0.90 to <1.50. Subjects with PAD who had pain at rest had slower walking velocity and poorer walking endurance than other subjects with PAD. In multiple linear regression analyses that included subjects with PAD only, ABI level was an independent predictor of 6-minute walk performance (regression coefficient = 159 ft/0.40 ABI units, P = .011), usual paced 4-meter walk (regression coefficient = .095 meters/sec/0.40 ABI units, P = .031), and maximal paced 4-meter walk (regression coefficient = .120 meters/sec/0.40 ABI units, P = .050) adjusting for age, sex, race, leg symptoms, and comorbid diseases known to affect functioning. Pain at rest was associated independently with the maximally paced 4-meter walk (-0.201 meters/sec, P = .024), but not with the other walks.

CONCLUSION

ABI level has a measurable and independent association with walking endurance and both usual and maximal walking velocity. These data suggest that PAD may impair lower extremity function by diminishing function of both Type I ("slow twitch") and Type II ("fast twitch") muscle fibers. Because walking velocity has important prognostic implications for functioning, these data also suggest that ABI may be used to identify patients at increased risk of mobility loss.

The effect of six months treatment with a 100 mg daily dose of dehydroepiandrosterone (DHEA) on circulating sex steroids, body composition and muscle strength in age-advanced men and women

OBJECTIVE

The biological role of the adrenal sex steroid precursors--DHEA and DHEA sulphate (DS) and their decline with ageing remains undefined. We observed previously that administration of a 50 daily dose of DHEA for 3 months to age-advanced men and women resulted in an elevation (10%) of serum levels of insulin-like growth factor-I (IGF-I) accompanied by improvement of self-reported physical and psychological well-being. These findings led us to assess the effect of a larger dose (100 mg) of DHEA for a longer duration (6 months) on circulating sex steroids, body composition (DEXA) and muscle strength (MedX).

SUBJECTS AND DESIGN

Healthy non-obese age-advanced (50-65 yrs of age) men (n = 9) and women (n = 10) were randomized into a double-blind placebo-controlled cross-over trial. Sixteen subjects completed the one-year study of six months of placebo and six months of 100 mg oral DHEA daily.

MEASUREMENTS

Fasting early morning blood samples were obtained. Serum DHEA, DS, sex steroids, IGF-I, IGFBP-1, IGFBP-3, growth hormone binding protein (GHBP) levels and lipid profiles as well as body composition (by DEXA) and muscle strength (by MedX testing) were measured at baseline and after each treatment.

RESULTS

Basal serum levels of DHEA, DS, androsternedione (A), testosterone (T) and dihydrotestosterone (DHT) were at or below the lower range of young adult levels. In both sexes, a 100 mg daily dose of DHEA restored serum DHEA levels to those of young adults and serum DS to levels at or slightly above the young adult range. Serum cortisol levels were unaltered, consequently the DS/cortisol ratio was increased to pubertal (10:1) levels. In women, but not in men, serum A, T and DHT were increased to levels above gender-specific young adult ranges. Basal SHBG levels were in the normal range for men and elevated in women, of whom 7 of 8 were on oestrogen replacement therapy. While on DHEA, serum SHBG levels declined with a greater (P < 0.02) response in women (-40 +/- 8%; P = 0.002) than in men (-5 +/- 4%; P = 0.02). Relative to baseline, DHEA administration resulted in an elevation of serum IGF-I levels in men (16 +/- 6%, P = 0.04) and in women (31 +/- 12%, P = 0.02). Serum levels of IGFBP-1 and IGFBP-3 were unaltered but GHBP levels declined in women (28 +/- 6%; P = 0.02) not in men. In men, but not in women, fat body mass decreased 1.0 +/- 0.4 kg (6.1 +/- 2.6%, P = 0.02) and knee muscle strength 15.0 +/- 3.3% (P = 0.02) as well as lumbar back strength 13.9 +/- 5.4% (P = 0.01) increased. In women, but not in men, an increase in total body mass of 1.4 +/- 0.4 kg (2.1 +/- 0.7%; P = 0.02) was noted. Neither gender had changes in basal metabolic rate, bone mineral density, urinary pyridinoline cross-links, fasting insulin, glucose, cortisol levels or lipid profiles. No significant adverse effects were observed.

CONCLUSIONS

A daily oral 100 mg dose of DHEA for 6 months resulted in elevation of circulating DHEA and DS concentrations and the DS/cortisol ratio. Biotransformation to potent androgens near and slightly above the range of their younger counterparts occurred in women with no detectable change in men. Given this hormonal milieu, an increase in serum IGF-I levels was observed in both genders but dimorphic responses were evident in fat body mass and muscle strength in favour of men. These differences in response to DHEA administration may reflect a gender specific response to DHEA and/or the presence of confounding factor(s) in women such as oestrogen replacement therapy.

Functional performance of older adults in a long-term care setting

Motivation has been identified as an important factor in the older adult's ability to perform functional activities. The purpose of this study was to explore functional performance and factors that have an impact on functional performance in nursing home residents. Participants included 44 White older adults from two nursing homes. The majority of the participants were female (84%). The mean age of the participants was 88 +/- 6.4 years and, on the average, they had been institutionalized for 2.85 +/- 2.8 years. Following data reduction of the predictors, two factors--motivation (efficacy beliefs and intrinsic motivation) and lower extremity function (contractures and standing balance)--were identified. In a stepwise multiple regression analysis, these two factors were the only variables that significantly predicted functional performance and accounted for 81% of the variance in function.

The impact of physical performance and cognitive status on subsequent ADL disability in low-functioning older adults

OBJECTIVES

The purpose of this study was to examine the independent contributions of physical performance and cognitive status to subsequent levels of ADL disability in low-functioning non-institutionalized older adults.

METHODS

A prospective cohort study included 416 women and 141 men 57 years or older who were living in the community and who reported substantial physical limitation. Physical performance and cognitive status were assessed at baseline in 1993. ADL disability was assessed at baseline and in two follow-ups in 1994 and 1995. Data were analysed with correlation analyses and linear multiple regressions.

RESULTS

Both physical performance and ADL disability at baseline were highly predictive of subsequent ADL disability. Although cognitive status was slightly related to (subsequent) ADL disability, we found no independent contributions of cognitive status to subsequent ADL disability.

CONCLUSIONS

Measures of both physical performance and ADL disability may identify older low-functioning adults who may benefit from interventions to prevent them from further disablement.

Physical fitness and functional limitations in community-dwelling older adults

BACKGROUND

Conceptual models of disability have focused on disease-specific factors as the primary cause of disability. Functional limitations in the performance of basic tasks are considered primary mediators on the causal pathway from disease to disability.

PURPOSE

The purpose of this study was to assess the association between three fitness components (cardiorespiratory, morphologic, and strength) and functional limitations.

METHODS

Analyses employed data collected upon 161 older adults (72.5 +/- 5.1 yr) who agreed to undergo baseline testing in a clinical trial.

RESULTS

After controlling for age, race, sex, education, depressive symptoms, and body mass index, all three fitness components were directly associated with functional limitations (P < 0.05). This study is the first to characterize a broad set of individual fitness components as they relate to functional limitations and the first to examine directly measured cardiorespiratory fitness within the context of existing disability models.

CONCLUSION

These findings suggest that low fitness is a risk factor for functional decline independent of disease processes.

Health-related fitness test battery for adults: associations with perceived health, mobility, and back function and symptoms

OBJECTIVE

To evaluate the health-related content validity of nine fitness tests by studying how low, mid, and high levels of fitness are associated with perceived health and musculoskeletal functioning.

DESIGN

Cross-sectional methodological study.

SETTING

A research institute for health promotion.

PARTICIPANTS

Middle-aged (37 to 57 years) men (n = 245) and women (n = 253), evenly selected from five age cohorts of a random population sample.

MAIN OUTCOME MEASURES

The odds ratios (ORs) of selected health outcomes for low (least fit 20%), mid (next 40%), and high (most fit 40%) fitness categories in the different tests adjusted for several possible confounders.

RESULTS

Cardiorespiratory fitness, as measured by 2-km walk test, was strongly and consistently associated with perceived health and mobility (stair climbing) in both genders (range of ORs, 2.4 to 17.6), and a somewhat weaker relationship was found with leg power and with leg strength (ORs, 2.5 to 7.2). Low fitness in back muscular endurance and upper-body strength were associated with mobility disability (ORs, 2.8 to 8.5) and with back dysfunction and pain (ORs, 2.9 to 6.1). High fitness in back endurance in men and in balance in women were related to positive back health (ORs, 2.5 to 3.7). Body mass index was associated with musculoskeletal disability in women (ORs, 2.4 to 5.3). Balance, leg strength, and leg flexibility in men; and leg power, trunk and leg flexibility in women were not associated with health outcomes.

CONCLUSIONS

Among a middle-aged population, the majority of the evaluated fitness tests demonstrated health-related validity by strong associations with perceived health and musculoskeletal functioning, and by weaker associations with back symptoms.

Lower-extremity functioning in older Mexican Americans and its association with medical problems

OBJECTIVE

To describe lower-extremity functioning in community-dwelling older Mexican Americans and to examine its relationship with medical problems.

DESIGN

Cross-sectional analyses of survey and performance-based data obtained in a population-based study employing area probability sampling.

SETTING

Households within selected census tracts of five Southwestern states: Arizona, California, Colorado, New Mexico, and Texas.

PARTICIPANTS

A total of 2873 Mexican Americans aged 65 years and older.

MEASUREMENTS

A multidimensional questionnaire assessing demographic, sociocultural, and health variables. Standardized tests of lower-extremity physical functioning included measures of standing balance, repeated chair stands, walking, and an overall summary measure.

RESULTS

Regression analyses revealed that being more than age 75 and female, having arthritis diabetes, visual impairments, or being obese or underweight were all significantly associated with performance on both individual and summary tests of lower-extremity functioning. In separate regression analyses, the total number of medical conditions was also associated with performance.

CONCLUSIONS

The likelihood of predicting performance or inability to complete tests of lower-extremity functioning was greatest for those aged 80 and older, those with arthritis or diabetes, and those with three or more medical conditions. Because of the high prevalence of diabetes in Mexican Americans, documentation of the association of diabetes with performance-based tests of lower-extremity functioning may help guide early interventions targeted to prevent progression to more severe limitations or disability.

Tiredness in daily activities at age 70 as a predictor of mortality during the next 10 years

This study examined whether self-reported tiredness in mobility and activities of daily living is predictive of mortality, when controlled for global self-rated health, smoking, and socio-demographic factors. The investigation is part of the 1984 longitudinal study of the residents of Glostrup, Denmark, born in 1914, and included 734 men and women who were interviewed about mobility, activities of daily living, self-rated health, smoking, and socio-demographic factors, when they were 70 years old. Ten years later, in November 1994, information about deaths was obtained from the Central National Register. When controlled for the other variables tiredness in mobility was an independent predictor of mortality during the next 10 years among both women and men. The finding persisted when the analysis was performed on a restricted sample of non-disabled 70-year-old people. The results in the present study indicate that we have identified a subgroup of independent elderly people who are at risk of dying earlier than others.

Osteoarthritis in older adults

OBJECTIVE

This review highlights the clinical and pathophysiologic features of osteoarthritis (OA) of the peripheral joints and discusses the current and future management options for this common but potentially disabling disease. This article also addresses the contribution of osteoarthritis to falls and functional impairment in older people.

DESIGN

A critical assessment of current data regarding the pathogenesis of osteoarthritis, current and future therapies, and the potential role of OA in falls and functional impairment in older people.

CONCLUSIONS

Osteoarthritis is the most prevalent articular disease in older adults. Disease markers that will detect early disease and allow early intervention with pharmacologic agents that modify, if not halt, disease progression are much needed, but they are presently unavailable. Current management should include safe and adequate pain relief using systemic and local therapies and should also include medical and rehabilitative interventions to prevent, or at least compensate for, functional deficits. Although OA can result in impaired mobility and lower extremity function, its contribution as a cause of recurrent falls or impaired self-care, relative to other comorbid conditions, remains ill-defined. Further analysis of the determinants of disability, loss of mobility and falls in older patients with OA is needed.

The impact of kyphosis on daily functioning

OBJECTIVES

To determine whether moderate or severe kyphosis is associated with decrements in physical function, especially mobility.

DESIGN

Cross-sectional analysis of a cohort study.

SETTING

The Johns Hopkins Functional Status Laboratory, a multidisciplinary, standardized, quantitative assessment center.

PARTICIPANTS

A total of 231 community-dwelling volunteers aged 59 and older who participated in a 1-day evaluation.

MEASUREMENTS

Age, gender, self report of physical function, standardized measurement of: kyphosis (both qualitatively clinical criteria and quantitative assessment), time to walk 5 meters (0.1 seconds), and time to climb a flight of stairs (0.1 seconds) at usual pace.

RESULTS

Using multivariate step-wise regression analysis, the presence and severity of kyphosis, measured qualitatively, was independently associated with time to walk 5 meters and to climb a flight of stairs (P = .015, P < .001, respectively), adjusting for moderate-severe scoliosis, heart rate response to exercise, arthritis, vertigo, age, and gender. Similarly, quantitative kyphosis was associated independently with stair climb time (P = .005). Qualitative kyphosis was also associated with difficulty reaching (OR = 2.21 (95% CI: 1.14 to 4.29)) and difficulty performing heavy housework (OR = 1.64 (95% CI: 1.03 to 2.61)), adjusting for prior diagnosis of moderate-severe scoliosis, prior diagnosis of arthritis, age, and gender.

CONCLUSION

Kyphosis, by both clinical and quantitative assessment, is associated with diminished function, especially performance of mobility tasks. This association should be verified prospectively. If predictive, the impact of kyphosis on physical function should be considered in osteoporosis prevention and treatment counseling.

Predictors of recovery in activities of daily living among disabled older persons living in the community

OBJECTIVE

To identify the factors that predict recovery in activities of daily living (ADLs) among disabled older persons living in the community.

DESIGN

Prospective cohort study with 2-year follow-up.

SETTING

General community.

PARTICIPANTS

213 men and women 72 years or older, who reported dependence in one or more ADLs.

MEASUREMENTS AND MAIN RESULTS

All participants underwent a comprehensive home assessment and were followed for recovery of ADL function, defined as requiring no personal assistance in any of the ADLs within 2 years. Fifty-nine participants (28%) recovered independent ADL function. Compared with those older than 85 years, participants aged 85 years or younger were more than 8 times as likely to recover their ADL function (relative risk [RR] 8.4; 95% confidence interval [CI] 2.7, 26). Several factors besides age were associated with ADL recovery in bivariate analysis, including disability in only one ADL, self-efficacy score greater than 75, Folstein Mini-Mental State Examination (MMSE) score of 28 or better, high mobility, score in the best third of timed physical performance, fewer than five medications, and good nutritional status. In multivariable analysis, four factors were independently associated with ADL recovery-age 85 years or younger (adjusted RR 4.1; 95% CI 1.3, 13), MMSE score of 28 or better (RR 1.7; 95% CI 1.2, 2.3), high mobility (RR 1.7; 95% CI 1.0, 2.9), and good nutritional status (RR 1.6; 95% CI 1.0, 2.5).

CONCLUSIONS

Once disabled, few persons older than 85 years recover independent ADL function. Intact cognitive function, high mobility, and good nutritional status each improve the likelihood of ADL recovery and may serve as markers of resiliency in this population.

Cerebral white matter changes (leukoaraiosis), stroke, and gait disturbance

OBJECTIVES

Leukoaraiosis, a radiological change of cerebral white matter thought to be caused by ischemia, is associated with gait disturbance. However, because of concomitant stroke and cerebral atrophy, the clinical relevance of leukoaraiosis is uncertain. We, therefore, sought to determine if leukoaraiosis is a predictor of gait disturbance after accounting for cerebral atrophy and stroke in patients with a high prevalence of cerebrovascular disease.

DESIGN

Cross-sectional observational study.

SETTING

Neurology service (inpatient and outpatient) of a Department of Veterans Affairs Hospital.

PARTICIPANTS

Consecutive sample of 130 patients, 127 men and three women.

MEASUREMENTS

The findings of a gait scale were correlated to vascular risk factors, neurological examination as quantified by the NIH stroke scale and supplemental motor scale, and to brain CT findings. Brain CT scans were rated for leukoaraiosis, cerebral infarction, and cerebral atrophy.

RESULTS

Gait disturbance was more frequent and more severe in subjects with leukoaraiosis, of whom 31% had mild and 49% moderate/severe gait disturbance compared with 27% with mild and 12% with moderate/severe gait disturbance in subjects without leukoaraiosis (P < .001). Leukoaraiosis, cerebral atrophy, a history of multiple strokes, and weakness and ataxia of the legs were independent predictors of gait disturbance. The proportion and severity of leukoaraiosis increased with increasing gait disturbance in subgroups without leg deficit (P < .001) and without multiple strokes (P < .001), but no association with leukoaraiosis was shown in patients with leg deficit or a history of multiple strokes (P = .037 and P = .186, respectively). Gait disturbance was more severe when both leukoaraiosis and cerebral atrophy were present (P = .019).

CONCLUSION

In our Veteran population, leukoaraiosis is an independent predictor of gait disturbance after accounting for stroke and cerebral atrophy. Although leukoaraiosis is a form of cerebrovascular disease, it appears to be most closely associated to gait disturbance in the absence of symptomatic stroke or leg deficit.

Geriatric rehabilitation: state of the art

OBJECTIVES

To provide a clinically useful conceptual framework for the evaluation and treatment of disability in older persons, to review the rehabilitation of common conditions affecting function in older persons, and to discuss the effects of the ongoing changes in the healthcare system on geriatric rehabilitation.

METHODS

MedLine search and review of relevant texts for information on (1) geriatric disability and its treatment, (2) recent high quality research, guidelines, and review articles relevant to the rehabilitation of conditions commonly causing geriatric disability, (3) effects of recent changes in the healthcare system on geriatric rehabilitation.

RESULTS

Several pertinent models for geriatric disability were identified. These are explicated, along with information on the epidemiology of geriatric disability and its causes and relevant clinical applications. Rehabilitation is reviewed for musculoskeletal disorders, stroke and peripheral vascular disease, amputation, cardiopulmonary disorders, hip fracture, and deconditioning. Changes in the healthcare system appear to be affecting geriatric rehabilitation, especially the advent of managed care; relevant articles and opinions are reviewed, along with strategies to accommodate these changes.

CONCLUSIONS

Our understanding of the causes of disability in the older population has improved significantly over the last decade. There has also been noteworthy progress in our knowledge about the effects of selected rehabilitation interventions, especially exercise-related interventions. However, the cost-effectiveness of many rehabilitative interventions remains unclear, particularly for differing patient groups across the continuum of care. More research will be needed to evaluate the effects of managed care on rehabilitation outcomes in older persons.

Promoting the health of senior citizens

Canada is experiencing a dramatic increase in the number of older people in its population. Adopting strategies that involve physician actions, a societal approach and individual participation may substantially improve the health of senior citizens. This article presents ways to improve the quality of life and reduce the risk of premature death through manoeuvres that can be initiated by physicians in the context of the periodic health examination. The authors highlight the role of evidence in choosing the most appropriate interventions, speculate on areas of future importance and emphasize a societal approach to population health.