Maintaining mobility in late life. I. Demographic characteristics and chronic conditions

Determinants of levels and changes of physical functioning in chronically ill persons: results from the GLOBE Study

STUDY OBJECTIVE

Declines in physical functioning are a common result of chronic illness, but relatively little is known about factors not directly related to severity of disease that influence the occurrence of disability among chronically ill persons. The aim of this study was to assess the effect of a large number of potential determinants (sociodemographic factors, health related behaviour, structural living conditions, and psychosocial factors).

DESIGN

Longitudinal study of levels and changes of physical functioning among persons suffering from four chronic diseases (asthma/chronic obstructive pulmonary disease (COPD), heart disease, diabetes, chronic low back pain). In 1991, persons suffering from one or more of these diseases were identified in a general population survey. Self reported disabilities, using a subset of the OECD disability indicator, were measured six times between 1991 and 1997. These data were analysed using generalised estimating equations, relating determinants measured in 1991 to disability between 1991 and 1997, and controlling for a number of potential confounders (age, gender, year of measurement, and type and severity of chronic disease).

SETTING

Region of Eindhoven (south eastern Netherlands).

PARTICIPANTS

1784 persons with asthma/COPD, heart disease, diabetes mellitus and/or low back pain.

MAIN RESULTS

In a "repeated prevalence" model, statistically significant (p<0.05) and strong associations were found between most of the determinants and the prevalence of disabilities. In a "longitudinal change" model, statistically significant (p<0.05) predictors of unfavourable changes in physical functioning were low income and excessive alcohol consumption, while we also found indications for effects of marital status, degree of urbanisation, smoking, and external locus of control.

CONCLUSIONS

Other factors than characteristics of the underlying disease have an important influence on levels and changes of physical functioning among chronically ill persons. Reduction of the prevalence of disabilities in the population not only depends on medical interventions, but may also require social interventions, health education, and psychological interventions among chronically ill persons.

Assessing the association of walking with health services use and costs among socioeconomically disadvantaged older adults

BACKGROUND

The costs of physical inactivity are beginning to be recognized. Research to pinpoint these costs will provide needed information for researchers and policy-makers to develop cost-effective physical activity promotion programs. We present the association of walking with health services use and costs within a sample of 695 older, urban primary care patients.

METHODS

A survey provided most data, but utilization and cost data were obtained from a medical records system. Multivariate models were developed to assess the association of walking with health services use and costs, adjusting for sociodemographic characteristics, chronic disease, health status, and previous utilization.

RESULTS

Thirty-eight percent of respondents reported walking 0 minutes per week, 49% walked 1 to 119 minutes, and 13% walked 120 minutes or more. In the multivariate analyses, a report of walking 120 or more minutes was associated with a lower risk of emergency room visit and hospital stay in the subsequent year. No association was found between walking and primary care visits and total cost.

CONCLUSION

These analyses suggest an association of walking 120 minutes or more with decreased emergency room visits (OR = 0.5, P = 0.046) and hospital stays (OR = 0.6, P = 0.034). This suggests that physical activity promotion among socioeconomically disadvantaged older adults has the potential to provide cost savings. This will not be known, however, until physical activity can be promoted and maintained among these adults.

Tiredness as determinant of subsequent use of health and social services among nondisabled elderly people

OBJECTIVE

To examine whether self-reported tiredness in daily activities at age 75 is an independent determinant of incident hospitalization and use of home services 5 years later.

METHODS

In all, 275 people participated in a prospective study in Glostrup, Denmark, when they were 75 and 80 years old. Four subgroups were created according to whether participants had been hospitalized or used home care in the year before the baseline study and whether or not they were disabled at the time. The key predictor variables were measured by two scales about tiredness in daily activities.

RESULTS

Nondisabled individuals who felt tired in their daily activities had about twice the risk of being hospitalized and of being users of home help 5 years later.

CONCLUSIONS

Because tiredness in daily activities is related to subsequent hospitalization and use of home help, it should be taken seriously in preventive services among elderly people.

Correlates of attributing new disability to old age. Study of Osteoporotic Fractures Research Group

OBJECTIVES

To describe women who attribute new disability to old age and to identify demographic, medical, behavioral, and psychosocial characteristics that correlate with attributing new disability to old age.

DESIGN

Prospective cohort study with 4-year follow-up.

SETTING

Four geographic regions of the United States.

PARTICIPANTS

9704 women aged > or = 67 years participating in the Study of Osteoporotic Fractures. Of these, 657 who reported no disability at baseline but at follow-up reported difficulty carrying out 1 or more of 13 functional activities were eligible for our analysis.

MEASUREMENTS

All women reporting difficulty in any functional activity at follow-up were asked "What is the main condition that causes you to have difficulty or prevents you from (doing the activity)?" and were shown a card listing 14 medical conditions as well as the option "old age," from which they could choose only one response. Women attributing difficulty or inability in 1 or more functional activities to old age were classified as attributing new disability to old age. We examined the relationship between attributing new disability to old age and the following characteristics measured at baseline: age, level of education, medical comorbidity, cognitive function, body mass index (BMI), gait speed, grip strength, visual acuity, physical activity level, smoking status, social network level, and depressed mood.

RESULTS

Overall, 13.5% of women attributed new disability to old age. Age was a strong independent correlate of attributing new disability to old age: compared with women age 67 to 69, the odds of attributing new disability to old age for women age 70 to 79 was 3.6 times as large (95% confidence interval [CI] = 1.6-8.3), and for women age 80 or over was 5.5 times as large (95% CI = 2.1-14.7). The only other characteristic that remained an independent correlate of attributing new disability to old age was grip strength; for each decile decrease in grip strength, a woman's odds of attributing new disability to old age increased by 9% (odds ratio [OR] = 1.09, 95% CI = 1.01-1.19).

CONCLUSIONS

Despite great advances in geriatric medicine, old age is still perceived as a causal agent in functional decline, especially among our oldest patients. Further study is needed to determine whether, how often, and under what circumstances older adults who attribute new disability to old age have medical conditions amenable to interventions that could preserve their functioning and improve their quality of life.

Disparate effects of socioeconomic status on physical function and emotional well-being in older adults

We tested the hypothesis that among community living older adults with relatively low and high socioeconomic status (SES), low SES is associated with both poorer emotional well-being and physical function. Ambulatory, community living older men and women (70-89 years of age) were recruited from outpatient geriatric assessment clinics in relatively high socioeconomic areas of greater Boston (High SES, N=47), and from an urban senior center in the inner city (Low SES, N=66). We assessed health status, mental health, upper and lower extremity strength and physical function. We found that health status was not significantly different in the two groups. Quadriceps strength (Low SES: 199+/-57 N; High SES: 190+/-56 N; p=0.531) and Up and Go times (Low SES: 14.3+/-3.1 sec; High SES: 16.7+/-9.5 sec; p=0.068) were not significantly different in the two groups, while grip strength was slightly higher in the Low SES group (Low SES: 22.8+/-6.45 kg; High SES: 20.07+/-7.55 kg; p=0.049). In contrast, subjects with Low SES tended to have an increased tendency towards depression. Scores on the Geriatric Depression Scale were 3.8+/-3.0 in Low SES, and 1.8+/-2.8 in High SES (p<0.001). We conclude that while health status and physical function were not worse in subjects with low SES, emotional well-being was markedly less compared to seniors with high SES. SES may have disparate effects on physical function and mental health, perhaps due to different compensatory mechanisms.

The effects of antidepressants on obstructed and unobstructed gait in healthy elderly people

BACKGROUND

Elderly patients treated with antidepressants for depression are at high risk for injury due to falling. The primary purpose of this study was to determine the effects of amitriptyline, desipramine, and paroxetine on the gait of healthy elderly subjects during unobstructed and obstructed (i.e., stepping over obstacles) gait. Psychomotor and mood tests were also performed.

METHODS

A randomized, crossover, four-period, double-blind, placebo-controlled laboratory trial was performed. Twelve healthy elderly subjects (average age, 67 years; range, 65-72 years) were tested. Subjects were assigned the three antidepressant drugs or a placebo in a random order. Single doses of amitriptyline 50 mg, desipramine 50 mg, paroxetine 20 mg, or placebo were given 4 hours prior to gait testing. Temporal-distance measures and kinematics of the lower trailing limb (i.e., limb going over obstacle last) were obtained.

RESULTS

Compared with placebo, amitriptyline significantly reduced gait velocity by as much as 8.0% (p = .028), cadence by as much as 4.9% (p = .012), angular velocity of hip flexion by as much as 10.0% (p = .004), and angular velocity of knee flexion by as much as 8.3% (p = 018) during the crossing strides when stepping over obstacles. Except for knee flexion angle, unobstructed gait was not affected. Amitriptyline affected integrative capacity of the central nervous system (CNS) and ability to concentrate as measured by psychomotor and mood tests.

CONCLUSIONS

The results for amitriptyline suggest that the subjects slowed their obstacle crossing speeds as a result of reduced CNS integrative capacities. Neither paroxetine nor desipramine significantly affected gait, psychomotor function, or mood.

Coimpairments as predictors of severe walking disability in older women

OBJECTIVE

Severe disabilities are common among older people who have impairments in a range of physiologic systems. It is not known, however, whether the presence of multiple impairments, or coimpairments, is associated with increased risk of developing new disability. The aim of this study was to determine the combined effects of two impairments, decreased knee-extension strength and poor standing balance, on the risk of developing severe walking disability among older, moderately-to-severely disabled women who did not have severe walking disability at baseline.

DESIGN

The Women's Health and Aging Study is a 3-year prospective study with 6 semi-annual follow-up data-collection rounds following the baseline.

SETTING

At baseline, knee-extension strength and standing balance tests took place in the participants' homes.

PARTICIPANTS

758 women who were not severely walking disabled at baseline.

MEASUREMENTS

Severe walking disability was defined as customary walking speed of < 0.4 meters/second and inability to walk one quarter of a mile, or being unable to walk.

RESULTS

Over the course of the study, 173 women became severely disabled in walking. The cumulative incidence of severe walking disability from the first to the sixth follow-up was: 7.8%, 12.0%, 15.1% 19.5% 21.2%, and 22.8%. In Cox proportional hazards models, both strength and balance were significant predictors of new walking disability. In the best balance category, the rates of developing severe walking disability expressed per 100 person years were 3.1, 6.1, and 5.3 in the highest- to lowest-strength tertiles. In the middle balance category, the rates were 9.6, 13.2, and 14.7, and in the poorest balance category 21.6, 12.7, and 37.1, correspondingly. The relative risk (RR) of onset of severe walking disability adjusted for age, height, weight, and race was more than five times greater in the group with poorest balance and strength (RR 5.12, 95% confidence limit [95% CI] 2.68-9.80) compared with the group with best balance and strength (the reference group). Among those who had poorest balance and best strength, the RR of severe walking disability was 3.08 (95% CI 1.33-7.14). Among those with best balance and poorest strength, the RR was 0.97 (95% CI 0.49-1.93), as compared with the reference group.

CONCLUSION

The presence of coimpairments is a powerful predictor of new, severe walking disability, an underlying cause of dependence in older people. Substantial reduction in the risk of walking disability could be achieved even if interventions were successful in correcting only one of the impairments because a deficit in only one physiologic system may be compensated for by good capacity in another system.

The persistent impact of breast carcinoma on functional health status: prospective evidence from the Nurses' Health Study

BACKGROUND

Although physical and emotional function after the diagnosis of breast carcinoma have been described in clinic populations, to the authors' knowledge no previous study has measured change from the preillness level of functional health status in community-dwelling women.

METHODS

The authors conducted a 4-year (1992-96) prospective study of functional recovery after breast carcinoma in a large sample of women, aged 54-73 years. They collected multidimensional measures of self-reported functional health status in 1992, before diagnosis of breast carcinoma, and again in 1996, to examine the risk of decline associated with incident breast carcinoma.

RESULTS

After adjustment for age, baseline functional health status, and multiple covariates, women who developed incident breast carcinoma were more likely to have experienced reduced physical function, role function, vitality, and social function and increased bodily pain compared with women who remained free of breast carcinoma. Risk of decline was attenuated with increasing time since diagnosis. Risk of decline in physical function was evident across all stages of breast carcinoma, even after adjustment for women undergoing treatment for persistent or recurrent disease. We found evidence that the risk of decline among breast carcinoma cases compared with healthy women was largest among those who were most socially isolated.

CONCLUSIONS

Breast carcinoma results in persistent declines in multiple dimensions of functional health status. These prospective data suggest that previous studies reporting no difference in physical function among breast carcinoma cases compared with disease free women underestimated the deleterious effect of the disease on function. Socially isolated women are an especially vulnerable group.

Subsystems contributing to the decline in ability to walk: bridging the gap between epidemiology and geriatric practice in the InCHIANTI study

BACKGROUND

Older patients are often referred to geriatricians because of complaints of progressive difficulties in walking. The diagnostic and therapeutic approach to these patients is complex. Multiple physiologic subsystems may influence the ability to walk, and no standard criteria are currently available to establish whether these subsystems are functioning within the normal range. To address this lack of knowledge we conducted the InCHIANTI study.

OBJECTIVE

To identify measures that clinicians can use to understand the causes of walking difficulties in older persons.

DESIGN

A population-based study of persons living in the Chianti geographic area (Tuscany, Italy).

PARTICIPANTS

1,453 persons (age-range 20-102 years; 91.6% of the eligible) selected from city registry of Greve in Chianti and Bagno a Ripoli (Tuscany, Italy), using a multistage sampling method.

MEASUREMENTS

Factors that influence walking ability were classified into six main physiologic subsystems: central nervous system, perceptual system, peripheral nervous system, muscles, bone/joints, and energy production/delivery. Measures of the integrity and functioning of each of these proposed subsystems were identified and administered to all participants.

CONCLUSIONS

Data collected in InCHIANTI will be used to identify the main risk factors that influence loss of the ability to walk in older persons, to define physiologic subsystems that are critical for walking, to select the best measures of their integrity, and to establish critical ranges in these measures that are compatible with "normal" walking ability. The final goal is to translate epidemiological research into a geriatric clinical tool that makes possible more precise diagnosis and more effective treatment in patients with walking dysfunction.

Morbidity and comorbidity in relation to functional status: a community-based study of the oldest old (90+ years)

OBJECTIVES

To describe health and functional status in the oldest old; to explore the relationships of morbidity and functional status; and to verify whether this relationship was modified by gender.

DESIGN AND SETTING

A community-based survey including all inhabitants aged > or = 90 living in central Stockholm, Sweden. All participants were clinically examined by physicians, cognitively assessed by psychologists, and interviewed by nurses. Diagnoses were made according to the International Classification of Diseases-Ninth Revision (ICD-9), the DSM-III-R criteria for dementia, and Katz index of activities of daily living.

PARTICIPANTS

Of the 698 subjects in the study population, 99 (14%) had died and 29 (4%) moved before examination. Of the remaining subjects, 502 (88.1%) were examined, and the refusal rate was 11.9%.

MEASUREMENTS

Age- and gender-specific prevalence figures, and age-, gender- and education-adjusted odds ratios (OR) were used.

RESULTS

Of 502 examined subjects, 19% had no disease and 73% were functionally independent. Dementia was the most prevalent disease among women (42.2%), and cardio- and cerebrovascular diseases were the most frequent among men (42.4%). Women had higher prevalences of dementia (adjusted OR = 2.1, 95% confidence interval (CI) 1.2-3.7) and fractures and musculoskeletal diseases (adjusted OR = 2.8, 95% CI 1.1-7.3), whereas men had a higher prevalence of malignancy (OR = 0.2, 95% CI 0.1-0.7). Women were more disabled than men independent of age, education, and number of diseases (adjusted OR = 2.2, 95% CI 1.1-4.3).

CONCLUSIONS

A great proportion of nonagenarians were functionally independent despite their advanced age. Further studies are needed to clarify the excess of disability among very old women.

Predicting elderly people's risk for nursing home placement, hospitalization, functional impairment, and mortality: a synthesis

Long-term care resources would be allocated more cost-effectively if care planning and medical/functional eligibility decisions were grounded more firmly in extant evidence regarding the risk of nursing home placement, hospitalization, functional impairment, and mortality. This article synthesizes the studies that longitudinally assess the predictors of each of these outcomes for the 65 and older population in the United States. A database was assembled containing 167 multivariate analyses abstracted from 78 journal articles published between 1985 and 1998. Findings show that 22 risk factors consistently predict two or more outcomes, including three that predict all four: worse performance on physical function measures not based on activities of daily living, greater illness severity, and prior hospital use. Findings should help prioritize variable selection choices of those setting eligibility criteria, allocating care resources, and doing descriptive studies. Gaps are shown to exist in the understanding of outcome effects of facility, market, policy, and other system attributes.

Health promotion and older people: the role of the general practitioner in Australia in promoting healthy ageing

OBJECTIVE

The Commonwealth Government's Enhanced Primary Care initiative supports measures to enhance the role of general practitioners (GPs) in promoting healthy ageing as part of a population health approach. This paper comments on how the health assessments can be conducted to best effect, to strengthen the role of GPs in primary care and to promote autonomy and independence in older people.

METHOD

The relevant literature was collated to produce a review of public health and health promotion approaches and to ascertain the effectiveness of health promotion interventions for older people. A broad definition of health promotion including primary, secondary and tertiary prevention was adopted.

RESULTS

The evidence base suggests there is scope for greater targeting of health promotion activities towards older people. The rationale for the Australian GP to assume a major health promotion role with their older patients is provided. Associated barriers and enablers are discussed.

CONCLUSIONS

Prevention of disability is a key public health issue. The new MBS items may enable systematic evaluation of function and assist healthy ageing for all older people, including the frail aged. An increase in the preventive advice given to older patients has the potential to increase healthy behaviours and alter health outcomes.

IMPLICATIONS

The annual health assessment items on the Medicare Benefits Schedule, by enabling the GP to focus on prevention and coordination of care, have the potential to improve the health, physical, psychological and social function of older Australians.

Longest held occupation in a lifetime and risk of disability in activities of daily living

OBJECTIVES

To examine the association between the longest held occupation in a lifetime and risk of disability in activities of daily living (ADL) among elderly people (65 years and older) in northern Taiwan.

METHODS

A case-control design was used nested within two cohorts of a total of 2198 elderly people who had been followed up either between 1993 and 1997 or between 1996 and 1997. Cases were 360 elderly people with ADL disability within the study period. For each case, two sex matched controls were randomly sampled from the pool of elderly people free from ADL disability. Occupational data were collected through interviews conducted in 1997. Performed job contents were classified into occupational categories and occupation based social classes. Unconditional logistic regression techniques were used to estimate relative risk and 95% confidence intervals (95% CIs) of ADL disability.

RESULTS

Compared with people who were former legislators, government administrators, or business executives and managers, workers in agriculture, animal husbandry, forestry, or fishing (odds ratio (OR) 1.9, 95% CI 1.1 to 3.5) and workers in craft and related trades (OR 1.9, 95% CI 1.1 to 3.4) had significantly increased risks of subsequent ADL disability. Differential risks of ADL disability were found across social classes, with a significant dose-response trend in which unskilled blue collar workers had an 1.8 times higher risk of ADL disability than higher social classes of white collar workers.

CONCLUSIONS

After adjustment for education, there was still an inverse relation between risk of ADL disability and social class. Although total control for all the known risk factors for ADL disability among elderly people was impossible, the results tend to suggest a potential for an effect of longest held occupation in a lifetime on risk of ADL disability.

Report of having slowed down: evidence for the validity of a new way to inquire about mild disability in elders

BACKGROUND

Mild disability in elderly persons may be detected by eliciting reports of modified task performance, even in the absence of reported difficulty. This study provides evidence for the validity of one type of task modification. namely, slowing, as a measure of mild walking disability.

METHODS

Community-dwelling elders (N = 287) were questioned about whether they were walking indoors as quickly as they had 1 year before and 10 years before. Construct validity was assessed by the degree to which responses to these two questions were logically consistent with a general decline in walking speed, and by determining whether reported slowing was associated with concurrent reports of difficulty walking and with measured gait speed. Predictive validity in subjects without reported difficulty walking was gauged by the association of reported slowing with adverse walking outcomes at 1-year follow-up.

RESULTS

Reports of slowing over 10- and 1-year periods were almost uniformly consistent with a general decline in speed. Reported slowing was significantly associated with reported difficulty walking and with slower gait speed. In the subgroup of elders initially reporting no difficulty walking, reported slowing significantly predicted incident difficulty walking at follow-up, as well as other adverse walking outcomes. For example, among elders who reported slowing, 7%, 10%, and 19% developed new difficulty walking indoors, new difficulty walking outdoors, or stopped walking for pleasure, compared with 0%, 0%, and 3% for those who had not reported slowing (p < .05).

CONCLUSIONS

This study provides evidence for the construct and predictive validity of one type of task modification, namely, slowing in indoor walking. This work contributes to the development of new methods for measuring mild disability, which may in turn form the basis for clinical interventions based on the early identification of functional problems.

Low-intensity exercise as a modifier of physical frailty in older adults

OBJECTIVE

To examine the effects of a 3-month low-intensity exercise program on physical frailty.

DESIGN

Randomized clinical trial.

SETTING

Regional tertiary-care hospital and academic medical center with an outpatient rehabilitation fitness center.

PARTICIPANTS

Eighty-four physically frail older adults (mean age, 83 +/- 4 yrs).

INTERVENTION

Three-month low-intensity supervised exercise (n = 48) versus unsupervised home-based flexibility activities (n = 36).

MAIN OUTCOME MEASURES

Physical performance test, measures of balance, strength, flexibility, coordination, speed of reaction, peripheral sensation.

RESULTS

Significant improvement was made by the exercise group on our primary indicator of frailty, a physical performance test (PPT) (29 +/- 4 vs 31 +/- 4 out of a possible 36 points), as well as many of the risk factors previously identified as contributors to frailty; eg, reductions in flexibility, strength, gait speed, and poor balance. Although the home exercise control group showed increases in range of motion, the improvements in flexibility did not translate into improvements in physical performance capacity as assessed by the PPT.

CONCLUSIONS

Our results suggest that physical frailty is modifiable with a program of modest activities that can be performed by virtually all older adults. They also indicate that exercise programs consisting primarily of flexibility activities are not likely to reverse or attenuate physical frailty. Although results suggest that frailty is modifiable, it is not likely to be eliminated with exercise, and efforts should be directed toward preventing the condition.

Mobility limitations in the Swedish population from 1968 to 1992: age, gender and social class differences

Mobility limitations are closely related to disability in old age. The study of mobility limitations in the population may improve the understanding of the development of disability, as well as gender and class patterns in disability in old age. Representative samples of the Swedish population between the ages of 18 and 75 years were interviewed in 1968, 1974, 1981, and 1991. A further sample of people aged 76+ years was interviewed in 1992. The questionnaire included the ability to walk 100 meters, to walk up and down stairs, and to run 100 meters. Mobility limitations begin to appear around age 40 years, and increase with age. In 1992 nearly none in the oldest age group (85+) could run 100 meters, and less than half could walk 100 meters, or go up and down stairs without difficulty. Between 1968 and 1991, the proportion of people with mobility limitations was reduced by one third, with the most prominent reduction among the oldest age groups. Women were more likely to report mobility limitations compared to men at all waves; however, the gender difference decreased between 1968 and 1991. Blue-collar workers had more mobility limitations than white-collar workers, and this discrepancy did not decrease over time. Mobility limitations often begin early in life, and differences between cohorts, men and women, and social classes can be seen well before the age of 50. The results suggest that gender differences in functional limitations among elderly people may decrease in the future, while social class inequalities are likely to persist.

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.

Gender differences in disability: evidence and underlying reasons

Women have greater longevity than men and represent a larger proportion of the expanding older population. Several health, disease, behavioral and sociodemographic factors contribute to the higher prevalence of disability in women compared to men. This paper presents a review of methodologic and epidemiologic considerations important to our understanding the gender differences in the prevalence of disability, and discusses underlying causes for these differences. Compared to men, women have a longer duration of life lived with disability, in part due to higher prevalence of non-fatal chronic conditions, constitutional factors such as lower muscle strength and lower bone density, and higher rates of life-style factors such as sedentary behavior and obesity. Several of these factors are modifiable, and provide important targets for researchers, clinicians, and public health practitioners in their efforts to reduce the burden of disability in the older population.

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.

Modifiable risk factors predict functional decline among older women: a prospectively validated clinical prediction tool. The Study of Osteoporotic Fractures Research Group

OBJECTIVE

To identify modifiable predictors of functional decline among community-residing older women and to derive and validate a clinical prediction tool for functional decline based only on modifiable predictors.

DESIGN

A prospective cohort study.

SETTING

Four geographic areas of the United States.

PARTICIPANTS

Community-residing women older than age 65 recruited from population-based listings between 1986 and 1988 (n = 6632).

MEASUREMENTS

Modifiable predictors were considered to be those that a clinician seeing an older patient for the first time could reasonably expect to change over a 4-year period: benzodiazepine use, depression, low exercise level, low social functioning, body-mass index, poor visual acuity, low bone mineral density, slow gait, and weak grip. Known predictors of functional decline unlikely to be amenable to intervention included age, education, medical comorbidity, cognitive function, smoking history, and presence of previous spine fracture. All variables were measured at baseline; only modifiable predictors were candidates for the prediction tool. Functional decline was defined as loss of ability over the 4-year interval to perform one or more of five vigorous or eight basic daily activities.

RESULTS

Slow gait, short-acting benzodiazepine use, depression, low exercise level, and obesity were significant modifiable predictors of functional decline in both vigorous and basic activities. Weak grip predicted functional decline in vigorous activities, whereas long-acting benzodiazepine use and poor visual acuity predicted functional decline in basic activities. A prediction rule based on these eight modifiable predictors classified women in the derivation set into three risk groups for decline in vigorous activities (12%, 25%, and 39% risk) and two risk groups for decline in basic activities (2% and 10% risk). In the validation set, the probabilities of functional decline were nearly identical.

CONCLUSIONS

A substantial portion of the variation of functional decline can be attributed to risk factors amenable to intervention over the short term. Using eight modifiable predictors that can be identified in a single office visit, clinicians can identify older women at risk for functional decline.

Health behaviors, social networks, and healthy aging: cross-sectional evidence from the Nurses' Health Study

Physical function is a significant component of health-related quality of life among older adults. Potential correlates of healthy aging, including health behaviors and social network characteristics, were examined among 56,436 US women aged 55-72 in 1992. Healthy aging was assessed by maintenance of physical function measured by four subscales of the Medical Outcomes Study Short Form (SF)-36 Health Survey: physical functioning; role limitations; freedom from bodily pain; and vitality. Individual health behaviors, defined as current smoking, alcohol consumption, sedentary behavior, and being overweight each contributed to significant decrements in functioning across all age-groups. After controlling for these health behaviors and other confounders (age, race, education, and co-morbid conditions), elements of a woman's social network were significantly correlated with functional status. Strong predictors of high functioning among older women were having close friends and relatives and presence of a confidant. For example, the absence of a confidant was associated with a 4.44 point reduction in physical functioning (95% CI: -7.0, -1.9), and a 5.68 point reduction in vitality (95% CI: -7.9, -3.4). These effects were comparable in magnitude to those observed among heavy smokers, or women in the highest category of body mass index.

The relationship between body composition and physical performance in older women

BACKGROUND

The relationship between age-associated change in body composition and physical disability is still unknown. Skeletal muscle mass declines with age in both sexes; however, since women have less muscle mass per unit of weight than men, these changes may be more debilitating in women.

OBJECTIVE

To evaluate the relationship between body composition and physical performance.

DESIGN

A cross-sectional study.

PARTICIPANTS

144 women aged 68 to 75 were selected randomly from the general population of Verona.

MEASUREMENTS

Body composition was evaluated using dual energy X-ray absorptiometry and bioimpedance. Physical performance was evaluated using a modified version of the Activities of Daily Living scale. Distance walked in 6 minutes was calculated, and isometric knee strength was tested.

RESULTS

Normal women had a significantly lower body mass index (BMI) and percent body fat. These women also had a higher ratio of body cell mass (BCM) and total fat free mass (FFM) than women with physical impairments. After adjusting for BMI, women in the lowest tertile of muscle strength had significantly lower BCM than those in the highest tertile.

CONCLUSIONS

These cross-sectional data show that although muscle strength is related to fat-free mass, disability in older women is associated with heavier BMI and with a higher percentage of body fat.

Exercise self-efficacy and its correlates among socioeconomically disadvantaged older adults

Self-efficacy has been shown to be one of the strongest, mutable predictors of exercise behavior. This report presents data on exercise self-efficacy and outcome expectations and their correlates within a stratified random sample of 729 urban, lower-income primary-care patients age 55 and older. Exercise self-efficacy scores were greater among persons with current exercise, no pain of fear of shortness of breath with exercise, and good self-rated health. Higher outcome expectations scores were associated with verbal persuasion from a doctor or from family and friends and positive attitudes and knowledge of exercise. Sociodemographic characteristics, environmental factors, and intrapersonal factors accounted for 31% of the variance in self-efficacy, but just 13% of the variance in outcome expectations. Further work on potential correlates and their measurement is needed to identify determinants of both outcome expectations and self-efficacy.

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.

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.

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.

Association of comorbidity with disability in older women: the Women's Health and Aging Study

There is substantial evidence that physical disability results from chronic diseases and that the number of chronic diseases is associated with the presence and severity of disability. There is some evidence that interactions between specific diseases are of import in causing disability. Beyond arthritis, however, little is known of the disease pairs that may be important to focus on in future research. This study explores the associations between multiple disease pairs and different types of physical disability, with the objective of hypothesis development regarding the importance of disease interactions. The study population comprised a representative sample of 3841 women 65 years and older living in Baltimore, screened for participation in the Women's Health and Aging Study. The study design was cross-sectional. An interviewer-administered screening questionnaire was administered regarding self-reported physical disability in 15 tasks of daily life, history of physician diagnosis of 14 chronic diseases, and MiniMental State examination. Task difficulty was empirically grouped into six subsets of minimally overlapping disabilities, with a comparison group consisting of those with no difficulty in any task subset. Multiple logistic regression models were fit assessing the relationship of major chronic diseases and of interactions of disease pairs with each disability subtype and with any disability, adjusting for confounders. Fourteen percent of the population reported mobility difficulty only; 5%, upper extremity difficulty only; 9%, both of these difficulties but no others; 7%, difficulty in higher function but not self-care tasks; 7%, self-care task difficulty but not higher function tasks; and 15%, difficulty in both higher function and self-care (weighted data). Almost all in the latter three groups had difficulty, as well, in mobility or upper extremity tasks. In regression models, specific disease pairs were synergistically associated with different types of disability. For example, important disease pairs that recurred in their associations with different disability types were the presence of arthritis and visual impairments, arthritis and high blood pressure, heart disease and cancer, lung disease and cancer, and stroke and high blood pressure. In addition, the type of disability that a disease was associated with varied, depending on the other disease that was present. Finally, when interactions were accounted for, many diseases were no longer, in themselves, independently associated with a given type of disability. Partitioning disability into six subtypes was more informative in terms of associations than was evaluating a summary category of "any disability." These findings provide a basis for further hypothesis development and testing of synergistic relationships of specific diseases with disabilities. If testing confirms these observations, these findings could provide a basis for new strategies for prevention of disability by minimizing comorbid interactions.

Functional ability among elderly people in three service settings: the discriminatory power of a new functional ability scale

The purpose is to assess the discriminatory power of the Avlund scales: (1) by assessing the ability of the scales to discriminate between three different populations of elderly people, and (2) by studying groups with a poor fit between use of formal home care and functional ability. The study included (A) all residents in new sheltered housing facilities (response rate 68%, n = 102), (B) a random sample of users of home care (response rate 67%, n = 435), and (C) a random sample of individuals not using home care (response rate 74%, n = 501). All participants were 60+ years old. Data were collected by personal interviews (group A) and by postal questionnaires (group B and C). Functional ability was measured by The Avlund Mob-T scale about tiredness related to mobility and the Mob-H scale about need of help to mobility. Both scales were able to distinguish the three sub-populations. The whole range of the Mob-T scale was used in all three subpopulations, and the whole range of the Mob-H scale was used among the oldest residents and the oldest users of home care. A small group of well-functioning users of home care (n = 52) was characterized by good self-rated health, good hearing, vision and memory abilities; they gave more help to others, had higher social participation, and lived alone (only the women). A somewhat lager group of poor functioning non-users of home care (n = 266) had the opposite characteristics. In addition, they were older, had a poor social network and poor social support.

Self-reported and performance-based functional status and associated factors among elderly men: the Finnish cohorts of the Seven Countries Study

Health and functional status were studied in 470 men aged 70-89, the survivors of the Finnish cohorts of the Seven Countries Study. We aimed to compare subjective (self-reported activity of daily living [ADL]) and objective methods (four physical performance tests) in the assessment of physical function and to identify which factors are related to physical function. Poor ADL and decreased physical performance were mainly explained by the same health-related factors. The strongest determinants of ADL were depressive symptomatology odds ratio [OR] 4.8, 95% confidence interval [CI] 2.7-8.8), osteoarthritis (OR 3.3, 95% CI 1.8-5.9), vertigo (OR 2.5, 95% CI 1.2-5.5) and diabetes (OR 2.3, 95% CI 1.2-4.6). Self-reported ADL and performance-based measures were in general strongly correlated with each other, although there was some discordance owing to the fact that these performance tests examine functional limitations, whereas the self-reported ADL reflects disability. The choice of which measurement to use in assessing functional status should be based on research objectives and the type of population under study.

Predictors of mobility and basic ADL difficulty among adults aged 70 years and older

We use data from the 1993-1995 Assets and Health Dynamics of the Oldest-Old survey to estimate predictors of onset of mobility difficulty, onset of basic activity of daily living (ADL) difficulty, and improvement to no mobility difficulty. Onset of mobility difficulty occurred among 20% of those with no difficulty at baseline (n = 2,857) and was most likely among those 85 years of age or over, women, those with a body-mass index of 30 or over, and those who reported lung disease, arthritis, frequent pain, and poor memory. For those with mobility difficulty at baseline (n = 1,871), improvement occurred among 24% and onset of basic ADL difficulty occurred among 25%. Improvement was more likely among those with difficulty in just one mobility item at baseline, and onset of ADL difficulty was most common among those with difficulty in three or more mobility items at baseline.

Preventing disability and managing chronic illness in frail older adults: a randomized trial of a community-based partnership with primary care

BACKGROUND

Effective new strategies that complement primary care are needed to reduce disability risks and improve self-management of chronic illness in frail older people living in the community.

OBJECTIVE

To evaluate the impact of a 1-year, senior center-based chronic illness self-management and disability prevention program on health, functioning, and healthcare utilization in frail older adults.

DESIGN

A randomized controlled trial.

SETTING

A large senior center located in a northeast Seattle suburb. The trial was conducted in collaboration with primary care providers of two large managed care organizations.

PARTICIPANTS

A total of 201 chronically ill older adults seniors aged 70 and older recruited through medical practices.

INTERVENTION

A targeted, multi-component disability prevention and disease self-management program led by a geriatric nurse practitioner (GNP).

MEASUREMENTS

Self-reported Physical function, physical performance tests, health care utilization, and health behaviors.

RESULTS

Each of 101 intervention participants met with the GNP from 1 to 8 times (median = 3) during the study year. The intervention group showed less decline in function, as measured by disability days and lower scores on the Health Assessment Questionnaire. Other measures of function, including the SF-36 and a battery of physical performance tests, did not change with the intervention. The number of hospitalized participants increased by 69% among the controls and decreased by 38% in the intervention group (P = .083). The total number of inpatient hospital days during the study year was significantly less in the intervention group compared with controls (total days = 33 vs 116, P = .049). The intervention led to significantly higher levels of physical activity and senior center participation and significant reductions in the use of psychoactive medications.

CONCLUSIONS

This project provides evidence that a community-based collaboration with primary care providers can improve function and reduce inpatient utilization in chronically ill older adults. Linking organized medical care with complementary community-based interventions may be a promising direction for research and practice.

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 relationship between ethnoracial group and functional level in older persons

The objective of this study was to determine: (1) the differences between blacks, Latinos, and whites in relation to functional level, (2) whether these differences could be entirely explained by differences in socioeconomic status (SES) for both blacks and Latinos, and (3) which SES indicators might account for differences in function. Data from the 1570 respondents in the Growing Older in New York City Study, a representative sample of black, Latino, and non-Latino white persons, age 65 years and over, were used. Latinos were significantly more functionally impaired than the other two ethnoracial groups, but this was accounted for by income, education, and the residential environment. Blacks were the least functionally impaired when income, education and the residential environment were controlled. Possible explanations for these results and implications for service delivery are discussed.

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.

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.

Do disease specific characteristics add to the explanation of mobility limitations in patients with different chronic diseases? A study in The Netherlands

STUDY OBJECTIVES

To determine whether disease specific characteristics, reflecting clinical disease severity, add to the explanation of mobility limitations in patients with specific chronic diseases.

DESIGN AND SETTING

Cross sectional study of survey data from community dwelling elderly people, aged 55-85 years, in the Netherlands.

PARTICIPANTS AND METHODS

The additional explanation of mobility limitations by disease specific characteristics was examined by logistic regression analyses on data from 2830 community dwelling elderly people.

MAIN RESULTS

In the total sample, chronic non-specific lung disease, cardiac disease, peripheral atherosclerosis, diabetes mellitus, stroke, arthritis and cancer (the index diseases), were all independently associated with mobility limitations. Adjusted for age, sex, comorbidity, and medical treatment disease specific characteristics that explain the association between disease and mobility mostly reflect decreased endurance capacity (shortness of breath and disturbed night rest in chronic non-specific lung disease, angina pectoris and congestive heart failure in cardiac disease), or are directly related to mobility function (stiffness and lower body complaints in arthritis). For atherosclerosis and diabetes mellitus, disease specific characteristics did not add to the explanation of mobility limitations.

CONCLUSIONS

The results provide evidence that, to obtain more detailed information about the differential impact of chronic diseases on mobility, disease specific characteristics are important to take into account.

Determinants of functional status in healthy Italian nonagenarians and centenarians: a comprehensive functional assessment by the instruments of geriatric practice

OBJECTIVE

To evaluate the physical ability and psychocognitive status of a population more than 90 years of age with regard to sociodemographic, behavioral, and biomedical variables known to affect functional status in old age.

DESIGN

A survey design was used.

SETTING

Emilia Romagna, Northern Italy.

PARTICIPANTS

Eighty-four healthy community-dwelling subjects aged 90 to 106 years.

MEASUREMENTS

Sociodemographic variables, health behavior, anthropometric indices, and serum DHEAS levels were recorded. Functional assessment was performed by instruments currently used in geriatric practice: the Mini-Mental State Examination (MMSE), Geriatric Depression Scale (GDS), and Activities of Daily Living (ADL) scale. A stepwise multiple regression analysis was performed.

RESULTS

GDS scores correlated directly with MMSE scores and inversely with ADL severity scores. Poor education, institutionalization, sensory impairment, muscular mass loss, and lower DHEAS levels were the variables with the highest correlation to functional impairment. Smoking, alcohol consumption, and marital status were relatively unimportant. An inverse association was found between DHEAS levels and dependency scores of single ADLs (continence, mobility).

CONCLUSION

Impaired cognitive and physical ability with no increase in depression prevalence was found in a sample of subjects more than 90 years of age free of major age-related disease. Muscular mass and DHEAS levels seem to play a role in maintaining physical independence. In turn, physical independence, as well as social and cultural factors, strongly affect the compliance of long-lived subjects with psychocognitive tests currently used in the clinical evaluation of younger old people, suggesting that these instruments are not reliable for screening for cognitive impairment and depression in the oldest old subjects.

The contribution of six chronic conditions to the total burden of mobility disability in the Dutch population

OBJECTIVES

This study assessed the proportions of the burden of mobility disability in the Dutch population that are attributable to musculoskeletal diseases, lung diseases, neurological disorders, heart diseases, diabetes, and cancer.

METHODS

National survey data were analyzed with an elimination technique that combines the results of logistic regression analysis and the disease prevalence.

RESULTS

Of the total prevalence of disability (20.5%), 33.7% can be attributed to these six chronic conditions. Musculoskeletal disorders account for the major part, whereas the contribution of cancer is very small.

CONCLUSIONS

The potential benefits of effective curative or preventive treatments for chronic conditions, in terms of reduction of the disability burden in the population, are limited.

The socioeconomic burden of fractures: today and in the 21st century

Hip fractures are a burden to both the individual and the community. Only 50% of patients regain the mobility and independence they enjoyed 12 months before the hip fracture occurred. Direct costs are high: about US$7,000 for the immediate hospital care and $21,000 in total costs for the first year. The numbers of hip fractures worldwide are projected to increase from 1.7 million in 1990 to 6.3 million in 2050 because of the aging of the population; therefore, the total cost of these fractures will also increase. Based on today's currency values and a cost of $21,000 per patient, the total cost of hip fractures in the year 2050 will be $131.5 billion. The costs and morbidity associated with other fractures, such as vertebral fractures, are less well defined. Because hip fractures are associated with the highest and most well-defined costs, morbidity, and mortality of all fragility fractures, models with high sensitivity can now be devised for evaluating the costs and benefits of interventions. These models are constructed using data on incidence, morbidity, mortality, and costs of fractures, along with the efficacy of an intervention, to estimate the impact of that intervention against osteoporosis. According to one model, the cost per hip fracture avoided is $48,600 if a 62-year-old woman with osteoporosis receives treatment with a drug that is administered for 5 years at $830/year and produces a 50% reduction in fracture rate. The cost per life-year saved is $30,600, and the cost per quality-adjusted life-year is $14,900. By comparison, using this model, treatment of a 62-year-old woman with a diastolic pressure of 95 mm Hg using a drug costing $420/year that reduces risk of stroke by 38% results in costs of $144,200 per stroke avoided, $17,800 per life-year saved, and $14,300 per quality-adjusted life-year. Health economic models allow for changes in assumptions, such as extent of compliance, effectiveness of therapy, and risk of side effects. Cost-effectiveness varies according to treatment and is highly sensitive to the estimated efficacy of treatment, patient compliance, age of the patient at the start of treatment, and fracture risk assigned to the patient. Greater cost-effectiveness occurs when treatments are more efficacious and when they are directed at patients with the highest risk of fracture.

Methodological challenges in measurements of functional ability in gerontological research. A review

This article addresses two important challenges in the measurement of functional ability in gerontological research: the first challenge is to connect measurements to a theoretical frame of reference which enhances our understanding and interpretation of the collected data; the second relates to validity in all stages of the research from operationalization to meaningful follow-up measurements in longitudinal studies. Advantages and disadvantages in different methods to do the measurements of functional ability are described with main focus on frame of reference, operationalization, practical procedure, validity, discriminatory power, and responsiveness. In measures of functional ability it is recommended: 1) always to consider the theoretical frame of reference as part of the validation process (e.g., the theory of "The Disablement Process"; 2) always to assess whether the included activities and categories are meaningful to all people in the study population before they are combined into an index and before tests for construct validity; 3) not to combine mobility, PADL and IADL in the same index/scale; 4) not to use IADL as a health-related functional ability measure or, if used, to ask whether problems with IADL or non-performance of IADL are caused by health-related factors; 5) always to make analyses of functional ability for men and women separately as patterns of functional ability and patterns of associations between other variables and functional ability often vary for men and women; and 6) to exclude the dead in analyses of change in functional ability if the focus is on predictors of deterioration in functional ability.

Predictors of five-year functional ability in a longitudinal survey of men and women aged 75 to 80. The 1914-population in Glostrup, Denmark

Data from a longitudinal study of aging-a Danish substudy within a Nordic comparative longitudinal Research on Ageing study (NORA)-is presented. The goal is to highlight easily measured factors, that are relevant to prevention and postponement of disability in the elderly. In a population-based, representative sample, the objectives were: to describe five-year outcome regarding death and functional ability to age 75 to 80, as well as individual changes in muscle strength, physical performance in simple function tests and self-reported physical activity, and relate "risk markers" to five-year outcome. Baseline values were obtained in 405 participants in the 1989-survey of the 1914-cohort in Copenhagen County. The 307 survivors were invited for the survey of 80-year olds in 1995. Outcome was measured as death, non-participation, decline, stability or improvement in two measures of mobility function (tiredness and dependency). Between ages 75 and 80, 24% died, 12% did not participate in the follow-up, 23% became tired performing mobility functions, 20% did not change but 21% became less tired; 19% became more dependent, 44% remained stable and only 2% improved in relation to dependency on help in mobility functions. "Stability" in mobility functions was related to ability to mount stairs, walking speed, mood and physical activity. Number of chronic diseases and low pulmonary function were only related to mobility in men. Among people who improved their function, many had rather low baseline-values, suggesting regression to the mean. Multiple logistic regression was conducted. The follow-up survey found that female participants were more physically active at baseline than non-participants. Five-year mortality was independently related to physical activity (RR = 0.41), pulmonary function in men (RR = 0.45/l increase) and muscle strength in women (RR = 0.65/N/kg increase). Dependency at follow-up in men was related to low physical activity at baseline (RR = 4.14), disability to mount a 50-cm step (RR = 4.07), two or more chronic diseases (RR = 3.36) and, only marginally significant, knee extension strength. In women only low physical activity was predictive (RR = 4.32). From baseline to follow-up, 34% of the population had reduced their physical activities. Knee extension strength was reduced from 6.0 to 4.4 N/kg in men, and from 4.2 to 3.3 N/kg in women. In the stair-mounting test, 44% could only attain one or more 10 cm steps lower than at baseline. A dose-response-relationship of declining muscle mass to functional limitations was observed in men and women at the age of 75 as well as the age of 80.

Does family support buffer the impact of specific chronic diseases on mobility in community-dwelling elderly?

The present study explores whether different structural (presence of partner and children) and functional (amounts of instrumental and emotional support provided by partner and children) family characteristics buffer the influence of chronic diseases on physical functioning. Logistic regression analyses were performed in a population-based sample of 2830 community-dwelling elderly people with chronic diseases as independent variable, and mobility difficulties as dependent variable, for separate strata of family characteristics. The presence of buffer effects was ascertained by comparing the associations between disease variables and mobility difficulties across the strata of family characteristics, using the odds ratios and 95% confidence intervals. Living together with a partner appears to buffer the association between the presence of one chronic disease and mobility difficulties, but no such effect is present among subjects with more than one disease. Regarding specific chronic diseases, partner presence has a beneficial influence only on the association between stroke and mobility difficulties, regardless of whether the partner provides little or much support. For patients with chronic non-specific lung disease (asthma, chronic bronchitis or pulmonary emphysema), a small amount of instrumental support (help with daily chores in and around the house) received from the partner is associated with a higher risk for mobility difficulties, compared to patients who receive a large amount of instrumental support and to patients who are not living with a partner. Neither the presence of children, nor the amounts of support received from them, influences associations between specific chronic diseases and mobility difficulties. The present study provides limited evidence supporting a buffer effect of family characteristics on the association between chronic diseases and mobility. Only in elderly people with a relatively low burden of disease does family support mitigate the adverse effects of disease on physical functioning.

Disability in older adults: evidence regarding significance, etiology, and risk

OBJECTIVES

This article synthesizes and assesses current evidence about the importance of physical disability to older adults. It then considers the applications of research findings to clinical geriatrics practice.

RESULTS

Physical disability is a major adverse health outcome associated with aging. Certain subgroups of older adults, including individuals with mobility difficulty, with preclinical functional changes, and persons who are hospitalized, are at particularly high risk of becoming disabled or experiencing disability progression. The major underlying causes of physical disability are chronic diseases, including both acute events, such as hip fracture and stroke and slowly progressive diseases such as arthritis and heart disease. These diseases appear to have task-specific effects; understanding this may assist in setting treatment and prevention goals. Comorbidity, particularly certain combinations of chronic diseases, is a strong risk factor for disability in itself. Recent trials indicate that clinical interventions may be able to prevent onset or progression of disability.

CONCLUSIONS

Available evidence now suggests clinical approaches to both treatment and prevention of disability and directions for defining optimal clinical care for the future.