Maintaining mobility in late life. II. Smoking, alcohol consumption, physical activity, and body mass index

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.

Self-report of difficulty in performing functional activities identifies a broad range of disability in old age

OBJECTIVE

To describe a broad range of physical disability by examining the association between a four-level measure of disability, based on self-report of difficulty in performing functional activities, and previously identified risk factors for disability.

DESIGN

Cross-sectional.

SETTING

Community-based.

PARTICIPANTS

A total of 2373 noninstitutionalized men and women aged 65 and older from the Veneto Region of Italy.

MEASUREMENTS

Odds ratios for the association of the four levels of disability (none, mild, moderate, and ADL disability) differentiated by this new measure with known risk factors for physical disability.

MAIN RESULTS

This summary measure of physical disability distinguished older persons with disability from the population typically classified as nondisabled. Twenty-one percent of study participants were identified as having Activities of Daily Living (ADL) disability (defined as self-report of difficulty in one or more ADLs), and an additional 40% had mild or moderate disability based on degree of difficulty in Instrumental Activities of Daily Living (IADLs) and physical functional activities. Hip fracture and lower extremity performance were strongly independently associated with each level of disability. The association of a range of established risk factors for disability and health care utilization measures with the levels of disability identified in our study, and the trend toward increasing odds with increasing disability, provide evidence of the construct validity of this measure.

CONCLUSIONS

Self-report of difficulty in performing functional activities identifies older persons with physical disability not ascertained by self-report of the need for help, the measure typically used to identify disability in older populations. Further studies should evaluate the potential for self-reported difficulty in functional activities to predict important disability-related outcomes.

Imbalance in an older population: an epidemiological analysis

Difficulties with balance are associated with limitations in activities of daily living. There is little information, however, about the epidemiology of imbalance. Imbalance, defined as the inability to maintain a full-tandem stand for 10 seconds, was assessed as part of an interview with 2,018 residents of Marin County, California, age 55 and older. The likelihood of imbalance was greater in women, those aged 85 and older, and those with less than 12 years of education. It was also associated with specific chronic conditions, including a history of hypertension, stroke, or cataracts. Even after adjusting for these conditions, imbalance was associated with reduced lower-body strength as well as poor short-term memory, hip pain, vision problems, abstention from alcohol, and current cigarette smoking. With those aged 85 and older representing the fastest growing age group in developed nations, imbalance may become a major health problem.

Recreational exercise in arthritis

For the person with arthritis, the consequences of prolonged inactivity add measurably, and unnecessarily, to disease-related impairments, functional limitation, and disability. Inadequate levels of regular physical activity also increase the risk of cardiovascular disease, hypertension, diabetes, and obesity. This article reviews the benefits of regular physical activity for general health as well as the literature on conditioning exercise in rheumatoid arthritis and osteoarthritis. Recommendations and guidelines are given for including conditioning exercise in comprehensive management.

"Lifestyle" interventions for promoting physical activity: a kilocalorie expenditure-based home feasibility study

The Centers for Disease Control and Prevention and the American College of Sports Medicine in cooperation with the President's Council of Physical Fitness and Sports recommended short periods of daily kilocalorie (calorie) expenditure with moderate-intensity physical activities to complement the currently existing recommendations. In this study the feasibility (adherence and safety) of employing calorie expenditure as the basis for prescribing a home-based walking program to healthy, community-dwelling men and women was examined. This was a 16-week pretest-posttest feasibility study of a home-based calorie-expenditure walking program conducted in an outpatient clinic in an academic medical center. Participants included 20 healthy, elderly, community-dwelling men and women. A 16-week home-based walking program was individually prescribed as a weekly amount of calorie expenditure increasing from an initial 300 calories per week to 1,200 calories per week (approximately 30 minutes of walking daily) during the final 6 weeks of the study. Adherence to the program was recorded individually in a diary (kept daily and reviewed at each visit), body weight, and walking pace. All but one participant were able to complete this 16-week program (95 percent adherence). That a calorie-based approach to promote physical activity among the elderly has a high adherence rate is suggested by these findings. Additional studies are necessary to define the potential role for this approach in promoting physical activity and improving health outcomes among the elderly.

Coronary heart disease risk factors in older persons

In most Western nations, coronary heart disease (CHD) is the leading cause of death and one of the most important causes of physical disability in persons over 65 years of age. The importance of traditional CHD risk factors has been well documented in middle-aged populations, whereas their role in older populations is still under debate. This paper reviews the epidemiologic evidence from observational studies and randomized clinical trials that established risk factors for CHD predict level of risk of CHD, and identify high risk individuals among older men and women. Hypertension and cigarette smoking have been clearly associated with an increased risk of CHD events, and their modification has been proven to be highly effective in the primary and secondary prevention of CHD in older persons. For other highly prevalent risk factors, such as lipid abnormalities, obesity and physical inactivity, evidence of an independent association with CHD risk has been demonstrated by the majority of observational studies. However, definitive proof from controlled clinical trials of the beneficial effects of their modification is still lacking in the older population. The role of estrogen replacement therapy in the primary and secondary prevention of CHD in old women is still an open question. In evaluating the impact of these risk factors in older persons, elements such as comorbidity, frailty, and age-related changes in risk profile should also be taken into consideration. Given the complexity of the relationship between risk factors and multiple disease statuses, other important outcomes, such as osteoporosis, cancer, falls and physical disability, should be considered when evaluating the risks and benefits of risk factor modifications in older persons.

Does walking decrease the risk of cardiovascular disease hospitalizations and death in older adults?

OBJECTIVES

The purpose of this study was to determine whether walking is associated with a reduced risk of cardiovascular disease hospitalization and death in community-dwelling older men and women.

DESIGN

A prospective study, with follow-up time of 4 to 5 years (average 4.2 years).

SETTING

A western Washington health maintenance organization.

PARTICIPANTS

Men and women aged 65 years and older from a random sample of HMO enrollees invited by mail to participate in a health promotion intervention trial (36% accepted the invitation and completed questionnaires). This report is based on 1645 older adults without severe disability and without history of heart disease. Vital status ascertainment was complete (100%), and only 2.6% did not complete the follow-up.

MEASUREMENTS

Reported frequency and duration of walking for exercise, work, errands, pleasure, and hiking in the 2 weeks before baseline were used to classify hours of walking per week. The two main outcomes were: (1) cardiovascular disease hospitalizations with a discharge diagnosis of coronary (ICD-9-CM 410-414) or other cardiovascular diseases (ICD-9-CM 390-409, 415-448) documented by computerized hospitalization records and (2) death. Numerous potential confounding factors were considered, including age, sex, treated high blood pressure, current estrogen use and chronic disease score (ascertained by computerized medical and pharmacy records), and ethnicity, education, income, physical function, self-rated health status, smoking, alcohol intake, and body mass index (ascertained by self-report on the mailed questionnaire).

RESULTS

Walking more than 4 hours/week was associated significantly with a reduced risk of cardiovascular disease hospitalization in both sexes combined compared with walking less than 1 hour/week (age and sex-adjusted relative risk = 0.69; 95% confidence interval, 0.52-0.90). This association was not altered by adjustment for baseline cardiovascular risk factors and indicators of general health status. The association was present in all age groups, among those with and without physical limitations, and also among those who did and did not also participate in more vigorous physical activities. Walking more than 4 hours/week was also associated with a reduced risk of death (age and sex-adjusted relative risk = 0.73; 95% confidence interval, 0.48-1.10), however, this association was substantially diminished by adjustment for cardiovascular risk factors and measures of general health status.

CONCLUSIONS

Walking more than 4 hours/week may reduce the risk of hospitalization for cardiovascular disease events. The association of walking more than 4 hours/week with reduced risk of death may be mediated by effects of walking on other risk factors. These findings provide much stronger evidence than previously available for advising older men and women to embark on or maintain a sustained program of walking to prevent cardiovascular disease events.

Associations of physical activity with performance-based and self-reported physical functioning in older men: the Honolulu Heart Program

OBJECTIVE

To examine the association of self-reported physical activity with performance-based and self-reported physical functioning measured 3 to 5 years later.

DESIGN

A population-based, longitudinal study.

SETTING

The island of Oahu, Hawaii.

PARTICIPANTS

Subjects were 3640 Japanese-American men older than 70 years of age.

MEASUREMENTS

Estimated daily energy expenditure evaluated from self-reported engagement in a variety of activities determined from a mail survey in 1988; physical functioning status determined from both self-report and performance-based measures 3 to 5 years later. The effect of physical activity on physical functioning scores was determined through multiple logistic regression and analysis of covariance techniques for subjects who had chronic diseases as well as those in a healthy subsample.

RESULTS

For the healthy subsample, those who were highly active in 1988 were more likely to have optimal function for the basic activities of daily living score (odds ratio 2.3; confidence interval (CI) 1.1 to 4.9), home management skills score (odds ratio 1.5; CI 1.1 to 2.1), and physical endurance-type tasks score (odds ratio 1.7; CI 1.2 to 2.4) than subjects classified as low active. A significant linear trend was found additionally across physical activity level for time to walk 10 feet and grip strength (P values < .001). Similar results were found for subjects with chronic diseases; however, most of the benefit of physical activity for this subsample occurred for subjects who were at least physically active at a moderate level.

CONCLUSION

Engaging in physical activity is predictive of a high level of physical functioning in older men with and without chronic diseases. Participation in at least moderate physical activity may be sufficient to maintain optimal physical functioning in subjects afflicted with chronic diseases.

Screening Efficiency of the Revised Physical Activity Readiness Questionnaire in Older Adults

The Physical Activity Readiness Questionnaire (PARQ) offers a safe preexercise screening of participants prior to physical activity involvement. However, the measure seems to screen out a relatively high proportion of apparently healthy older adults. In an attempt to improve this situation, an expert panel convened by Fitness Canada worked to revise the measure (rPARQ). The present study compares the number of exclusions resulting from the original and revised PARQ instruments in older adults (84 men, 85 women;Mage 76.5 yrs). The number of participants screened out by the rPARQ decreased significantly (p< .001), from 139 to 105. Agreement between measures was achieved in 78.7% of the participants (Cohen's kappa = .50). In an effort to promote physical activity involvement, researchers and practitioners are encouraged to consider the use of the recently developed rPARQ over the PARQ as a preexercise screening alternative.

Assessing risk for the onset of functional dependence among older adults: the role of physical performance

BACKGROUND

Approximately 10% of nondisabled, community-dwelling adults aged 75 years and older lose independence in basic activities of daily living (ADLs) each year. The purpose of this study was to evaluate whether simple tests of physical performance could identify older adults, independent in their basic ADLs, who were at increased risk for the onset of functional dependence.

METHODS

Among a representative cohort of 1103 community-dwelling adults aged 72 years and older, we evaluated the 664 subjects who were cognitively intact and independent in their basic ADLs at the baseline interview. All cohort members had undergone a comprehensive assessment, including a battery of qualitative and timed performance tests. The main outcome event was the onset of functional dependence, defined as a new disability in one or more of the seven basic ADLs at the 1-year follow-up.

RESULTS

Functional dependence developed in 53 (9%) of the 563 subjects who had complete data at the 1-year follow-up. Eight of the 12 qualitative tests and all six of the timed tests were significantly associated (P < .05) with the onset of functional dependence. Both qualitative and timed performance tests demarcated subjects into groups at low and high risk for functional dependence. Four timed tests--chair stands, rapid gait, 360 degrees turn, and bending over--showed a threshold phenomenon, where the rate of new dependence increased slowly with worsening performance until a critical point (or threshold) was reached, and the rate of dependence increased substantially. For timed chair stands, for example, the rates of functional dependence within quarters of worsening performance were 5.3%, 6.3%, 6.7%, and 16%. The risk of functional dependence was markedly elevated (30%-50%) for subjects who were unable to perform the timed tests.

CONCLUSIONS

Several simple tests of physical performance were strongly associated with the onset of functional dependence. These results support the potential use of physical performance tests to develop a risk assessment strategy that could identify subgroups of older persons, independent in all ADLs, who are at increased risk for functional dependence.

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

BACKGROUND

Functional assessment is an important part of the evaluation of elderly persons. We conducted this study to determine whether objective measures of physical function can predict subsequent disability in older persons.

METHODS

This prospective cohort study included men and women 71 years of age or older who were living in the community, who reported no disability in the activities of daily living, and who reported that they were able to walk one-half mile (0.8 km) and climb stairs without assistance. The subjects completed a short battery of physical-performance tests and participated in a follow-up interview four years later. The tests included an assessment of standing balance, a timed 8-ft (2.4-m) walk at a normal pace, and a timed test of five repetitions of rising from a chair and sitting down.

RESULTS

Among the 1122 subjects who were not disabled at base line and who participated in the four-year follow-up, lower scores on the base-line performance tests were associated with a statistically significant, graduated increase in the frequency of disability in the activities of daily living and mobility-related disability at follow-up. After adjustment for age, sex, and the presence of chronic disease, those with the lowest scores on the performance tests were 4.2 to 4.9 times as likely to have disability at four years as those with the highest performance scores, and those with intermediate performance scores were 1.6 to 1.8 times as likely to have disability.

CONCLUSIONS

Among nondisabled older persons living in the community, objective measures of lower-extremity function were highly predictive of subsequent disability. Measures of physical performance may identify older persons with a preclinical stage of disability who may benefit from interventions to prevent the development of frank disability.

Preventing disability and falls in older adults: a population-based randomized trial

OBJECTIVES

Because preventing disability and falls in older adults is a national priority, a randomized controlled trial was conducted to test a multicomponent intervention program.

METHODS

From a random sample of health maintenance organization (HMO) enrollees 65 years and older, 1559 ambulatory seniors were randomized to one of three groups: a nurse assessment visit and follow-up interventions targeting risk factors for disability and falls (group 1, n = 635); a general health promotion nurse visit (group 2, n = 317); and usual care (group 3, n = 607). Data collection consisted of a baseline and two annual follow-up surveys.

RESULTS

After 1 year, group 1 subjects reported a significantly lower incidence of declining functional status and a significantly lower incidence of falls than group 3 subjects. Group 2 subjects had intermediate levels of most outcomes. After 2 years of follow-up, the differences narrowed.

CONCLUSIONS

The results suggest that a modest, one-time prevention program appeared to confer short-term health benefits on ambulatory HMO enrollees, although benefits diminished by the second year of follow-up. The mechanisms by which the intervention may have improved outcomes require further investigation.

Functional status and mobility among elderly women with lower extremity arterial disease: the Study of Osteoporotic Fractures

OBJECTIVE

To investigate the relationship between lower extremity arterial disease, functional status, and mobility among elderly women.

DESIGN

Cross-sectional study.

SETTING

Community.

PARTICIPANTS

1492 healthy white women, 65 years of age or older, residing in a rural community, able to walk without the assistance of another person, and enrolled in the Pittsburgh clinic of the multicenter Study of Osteoporotic Fractures. Those with bilateral hip replacement were excluded.

MEASUREMENTS

Ankle/arm index (AAI); instrumental activities of daily living (IADLs); measures of recent physical activity, muscle strength, gait and balance; general demographic, lifestyle, and physical variables.

RESULTS

Women with lower extremity arterial disease (defined as an AAI of 0.9 or less) were more likely to report difficulty with one or more IADLs than were women free of this disease. After adjusting for age and other potential confounders, only difficulty with walking 2-3 blocks remained highly correlated with disease (relative risk (RR) 2.8, 95% confidence interval (CI) 1.6, 4.8). Several measures of physical activity were inversely and independently related to a low AAI. Muscle strength in the hip, arm, knee, and hand and measures of static and dynamic balance were correlated with low AAI in the univariate analysis, but most of these trends were not statistically significant after adjustment for age and other confounders. Exclusion of women with symptomatic arterial disease did not substantially affect the results obtained.

CONCLUSION

Women with mild, predominantly subclinical, lower extremity arterial disease living in the community have decreased functional status and mobility.

Disability and severe gastrointestinal hemorrhage. A prospective study of community-dwelling older persons

OBJECTIVE

To describe the occurrence of severe gastrointestinal bleeding in community-dwelling older persons and to examine whether disability is a risk factor for this life-threatening condition independent of other known predictors.

DESIGN

Prospective cohort survey.

SETTING

Three communities of the Established Populations for Epidemiologic Studies of the Elderly (EPESE).

PARTICIPANTS

8205 persons age > or = 68 years.

MEASUREMENTS

The hospital discharge diagnoses provided by the Medicare Provider Analysis and Review files and the death certificates were prospectively surveyed for 3 years. Those with at least 1 discharge diagnosis of gastrointestinal bleeding and who received a blood transfusion or died were identified as cases of severe gastrointestinal hemorrhage. Physical disability, cognitive function, smoking and alcohol intake habits, body mass index, blood pressure, chronic conditions, number of hospital admissions in past year and medications taken were assessed at baseline.

RESULTS

The occurrence rate of severe gastrointestinal bleeding was 10.8 per 1000 person-years (241 events/22,277 person-years). In proportional hazards regression models, compared with no disability, > or = 1 disabilities in the Rosow-Breslau scale (RR = 2.1, 95% CI = 1.5-2.9), and > or = 1 ADLs limitations (RR = 3.1, 95% CI = 2.1-4.6) independently predicted gastrointestinal hemorrhage after adjusting for age, gender, body mass index, comorbidity, number of hospital admissions, blood pressure, intake of coumarin, corticosteroids, aspirin and other nonsteroidal anti-inflammatory drugs.

CONCLUSIONS

In this prospective analysis, disability is an independent predictor of gastrointestinal hemorrhage. Further studies are needed to explain the mechanisms by which disability may cause gastrointestinal hemorrhage. Because physical disability is potentially modifiable, strategies to lower the risk of gastrointestinal bleeding should be evaluated.

Predictors of physical disability after age 50. Six-year longitudinal study in a runners club and a university population

Predictors of disability were studied over 6 years among 50- to 80-year-old members of a runners club (N = 407) and a university population (N = 299). Data have been collected annually since 1984 on sociodemographic characteristics, health habits, medical history, medication use, family history, psychological parameters, and physical disability as measured by the Health Assessment Questionnaire. Members of the runners club, compared to university participants, had better overall health and less disability at baseline (0.03 versus 0.08) and at 6-year follow-up (0.04 versus 0.24). Predictors of greater subsequent disability among university participants were greater baseline disability, greater medication use, greater number of pack-years of cigarette smoking, older age, being unmarried, higher blood pressure, history of arthritis, and less physical activity compared to one's peers. In addition, changes in characteristics during follow-up that were independently associated with greater disability were development of joint pain, arthritis, or bone fracture and increased body mass index. Predictors of greater disability in the runners group included greater baseline disability, being a nonrunner at baseline, greater dietary salt intake, more years of running at baseline, and greater frequency of physician visits for running injuries. Greater disability in this group also was associated with increases in medication use, declining alcohol consumption, and development of joint pain over 6 years. Results of this study suggest that physical disability is linked to a constellation of characteristics, health habits, medical history, comorbidities, and marital status. While self-selection bias cannot be ruled out entirely, these data are consistent with the hypothesis that those who engage in high levels of physical activity beyond middle age will continue to maintain better functional abilities.

Correlates of impaired function in older women

OBJECTIVE

To determine the factors associated with impaired function in older women.

DESIGN

Cross-sectional analysis of baseline data collected for a multicenter, prospective study of risk factors for osteoporotic fractures.

SETTING

Four clinical centers in Portland, Oregon, Minneapolis, Minnesota, Baltimore, Maryland, and the Monongahela Valley, Pennsylvania.

PARTICIPANTS

A total of 9,704 ambulatory, non-black women, aged 65 years and older, recruited from population-based listings.

MEASUREMENTS

Independent variables, including demographic and historical information (medical conditions, health habits, and medications) and physiologic measures (anthropometry, blood pressure, mental status, vision, and neuromuscular performance) were obtained from a baseline questionnaire, interview, and examination. Measurement of function was assessed by self-reported ability to perform six physical and instrumental activities of daily living (ADL) and impaired function (dependent variable) was defined as difficulty performing three or more physical and instrumental ADLs.

RESULTS

In order of decreasing strength of association, hip fracture, osteoarthritis, parkinsonism, slower walking speed, lower hip abduction force, back pain, greater Quetelet index, osteoporosis, former alcohol use, stroke, never drinking alcohol, lower mental status, use of anxiolytics and/or sleeping medications, inability to hold the tandem position, postural dizziness, cataracts, greater waist to hip ratio, lower physical activity in the past year, greater lifetime cigarette consumption, and lower grip strength were independently associated with impaired function in multivariate analyses. Age, low educational level, diabetes, current heavy alcohol use, postural hypotension, depth perception, and contrast sensitivity were not independent predictors. A combination of neuromuscular performance measures, including decreased muscle strength and impaired balance and gait, appeared to account for the effect of age on disability.

CONCLUSION

A combination of many factors, including medical conditions, health habits such as obesity, smoking, alcohol abstinence, and physical inactivity, and direct measures of neuromuscular performance are associated with impaired function in older women.

Physical activity epidemiology as applied to elderly populations

Physical activity epidemiological studies provide one of many types of research evidence that are necessary to assess the importance of physical activity to health. Available epidemiological evidence, when coupled with relevant experimental and clinical research, suggests that physical activity has the potential to favourably influence the development and progression of a variety of chronic diseases and conditions that are a burden to public health. The evidence is only beginning to emerge for elderly populations, however, thereby highlighting an important void in our scientific knowledge. Attempting to increase the level of physical activity of elderly people raises three important issues. First, improving adherence to a physically active life-style requires assistance of behavioural scientists, either through direct intervention, or through research that can help the elderly identify and overcome impediments to physical activity. Second, many elderly people have diseases that can limit their physical ability, but exercise scientists can assist by prescribing exercise that is both efficacious and safe given the level of limitation. Third, the number of injuries may increase with increased physical activity in elderly persons. Epidemiologists and exercise scientists working in the area of injury control can determine which activities are safe at specific levels of physical ability and function. To quote one of the originators of exercise physiology, Per Olaf Astrand (1992), 'As a consequence of diminished exercise tolerance, a large and increasing number of elderly people will be living below, at, or just above "thresholds" of physical ability, needing only a minor intercurrent illness to render them completely dependent'. Physical activity can help to push back that 'threshold of physical ability' and thereby improve physical functioning. As physical function improves, there is a propensity to perform even greater amounts of physical activity that may be essential to the quality and perhaps quantity of life for an elderly person.