Comorbidity and its impact on disability

Self-reported causes of physical disability in older people: the Cardiovascular Health Study. CHS Collaborative Research Group

OBJECTIVE

To determine the major conditions and symptoms reported to cause difficulty in 17 physical tasks of daily life and the criterion validity of self-report of diseases given as the causes of the difficulty in functioning, in community-dwelling older people.

DESIGN

Cross sectional analyses of data obtained in an observational cohort study.

SETTING

Research clinics in four US communities: Winston-Salem, NC, Hagerstown, MD, Pittsburgh, PA, and Sacramento, CA.

PARTICIPANTS

5201 community-dwelling people > or = 65 years old.

RESULTS

Arthritis and other musculoskeletal diseases were given as the primary causes of difficulty in performing physical tasks by 49.0% of the participants reporting difficulty in any task, followed by heart disease (13.7%), injury (12.0%), old age (11.7%), lung disease (6.0%), and stroke (2.9%). The self-reports of diseases that caused disability varied by task. Whereas arthritis was given as a cause of difficulty in most of the 17 different tasks, heart and lung disease were more likely to be reported as causing difficulty with activities requiring high aerobic work capacity such as walking one-half mile or doing heavy housework. Stroke was more likely to be reported as causing difficulty with use of the upper extremities and in performing basic activities of daily living. There was a high degree of consistency (91%) between the diseases and symptoms reported to cause disabilities. The percentage of people who reported a disease as the cause of their difficulty performing a task and had independent confirmation of the diagnosis was 85% in men and 71% in women, and varied according to type of disease and the individual's cognitive status and health status.

CONCLUSION

These data suggest that age-related chronic diseases are important causes of disability in older people but that the type of disability is dependent on the underlying disease that causes the disability. Also, self-report of the cause of disability appears to be generally accurate but is influenced by gender, health status, and type of disease.

Education and training of aged-care providers

Population ageing has become a global concern. As persons age they are likely to experience multiple changes, declines, and losses, resulting in multifaceted needs. Psychosocial needs are varied and diverse, reflecting the extreme heterogeneity of the older population and the frequent co-morbidity of physical and mental problems. Training of care providers to work with older people requires an interdisciplinary focus, with biological, psychological, and social aspects of ageing as integral parts of the curriculum. Models for training of aged care professionals include the integration, separate course, area of concentration, and interdisciplinary approaches. In addition, supervised experiences and training in interpersonal skills are required for all service providers. The applications of training models in gerontological and counselling training are described. Implications for education and training of aged-care providers are discussed.

The relationship between disease and function and perceived health in very frail elders

OBJECTIVE

To study associations between disease and observed function and self-perceived health in very frail elders.

DESIGN AND SETTING

Cross-sectional survey of nine nursing homes in San Antonio, TX.

PARTICIPANTS

194 elderly long-stay nursing home residents dependent in at least two ADLs and without severe cognitive impairment.

MEASURES

Burden of disease (BOD) was chart abstracted using a standardized protocol that assessed types and severities of 59 categorizations of chronic and acute medical conditions. Observed function and self-perceived health status were assessed independently by the Katz Activities of Daily Living scale (ADL) and the Sickness Impact Profile (SIP), respectively.

RESULTS

Summary BOD scores had a low, but statistically significant, univariate correlation with ADL scores (r = 0.21, P = 0.003) and no significant correlation with SIP scores (R = -0.008). Multiple linear regression analyses, including the 24 most frequent disease categories, showed that disease explained significant amounts of ADL (r2 = 0.25, P = 0.001) and borderline significant amounts of SIP (r2 = 0.16, P = 0.11). Models including both disease and sociodemographic, cognitive, and affective variables showed disease added significant incremental explantation beyond the other factors to ADL (incremental r2 = 0.14, P = 0.04), but not to SIP (incremental r2 = 0.08, P > 0.10).

CONCLUSIONS

Disease, observed function, and self-perceived health status are separate, but interrelated entities, with disease having a stronger relationship to observed function than self-perceived health. Comprehensive assessment of frail elders may need to include all three areas, and studies that focus on one area should take into account the other two as potential important covariates.

Disease, impairment, disability and social handicap: a community based study of people aged 70 years and over

The aim of this research was to investigate the prevalence of disability in a total population-based sample aged 70 years and over, the social handicap resulting from the disability and the diseases and impairments contributing to disability in the most disabled subjects. From the initial sample of 856 subjects, 782 (91.4%) participated. Disability in the tasks examined varied from 1.3% of subjects unable to feed themselves to 24.4% unable to carry out housework. In the 74 most disabled subjects comorbidity was common. The major clinical disorders that contributed to impairment and disability were heart failure, osteoarthritis, stroke and dementia. Those who were disabled were considerably more likely to be handicapped than those not disabled (odds ratio 6.65, 95% confidence interval 4.73-9.36). When social support was considered, the estimated risk of handicap associated with disability ranged from 3.19 (95% CI 1.92-5.30) for the subset of subjects who had a spouse, to 52.00 (95% CI 4.03-670.6) for subjects without emotional support.

Association of visual impairment with mobility and physical function

OBJECTIVE

To examine the association of distant vision and physical function in the population of older adults.

DESIGN

Cross-sectional and cohort study.

PARTICIPANTS

5143 older residents of three communities (Established Populations for the Epidemiologic Studies of the Elderly) who were interviewed in 1988-89, including residents of two communities who were re-interviewed 15 months later (n = 3133, 97% of those eligible).

MEASURES

Visual acuity screening, self-reported activities of daily living and mobility, and objective physical performance measures of balance, walking, and rising from a chair.

RESULTS

Limitations in mobility, activities of daily living, and physical performance were associated with worse visual function. In prospective analyses controlling for potential confounders, participants with severe visual impairment had 3-fold higher odds of incident mobility and activity of daily living limitations than those with acuity of 20/40 or better (P < 0.001). In prospective analyses investigating the relationship of vision with improvement in function, those with poor vision were about half as likely to improve as those with better acuity, but this relationship was only statistically significant for improvement in mobility limitations.

CONCLUSIONS

Distant visual function appears to play an important role in physical function, particularly for mobility. An intervention to improve vision in at-risk elders might preserve function and prevent disability; this warrants further investigation.

The effects of specific medical conditions on the functional limitations of elders in the Framingham Study

OBJECTIVES

The purpose of this study was to identify associations between specific medical conditions in the elderly and limitations in functional tasks; to compare risks of disability across medical conditions, controlling for age, sex, and comorbidity; and to determine the proportion of disability attributable to each condition.

METHODS

The subjects were 709 noninstitutionalized men and 1060 women of the Framingham Study cohort (mean age 73.7 +/- 6.3 years). Ten medical conditions were identified for study: knee osteoarthritis, hip fracture, diabetes, stroke, heart disease, intermittent claudication, congestive heart failure, chronic obstructive pulmonary disease, depressive symptomatology, and cognitive impairment. Adjusted odds ratios were calculated for dependence on human assistance in seven functional activities.

RESULTS

Stroke was significantly associated with functional limitations in all seven tasks; depressive symptomatology and hip fracture were associated with limitations in five tasks; and knee osteoarthritis, heart disease, congestive heart failure, and chronic obstructive pulmonary disease, were associated with limitations in four tasks each.

CONCLUSIONS

In general, stroke, depressive symptomatology, hip fracture, knee osteoarthritis, and heart disease account for more physical disability in noninstitutionalized elderly men and women than other diseases.

Estimates and determinants of valid self-reports of musculoskeletal disease in the elderly

This study examined the extent and nature of bias associated with self-reported versus standardized physician-examination/assessment-based accounts of musculoskeletal disease in a sample of 406 persons chosen to represent an aging and dependency continuum. Prevalence of musculoskeletal disease based on standardized physician examination/assessments was 97%. Using the standardized findings as the criterion, the self-report underestimated prevalence by 16%. Overall, the results indicated that self-reports of musculoskeletal conditions by the elderly capture the vast majority of persons with painful or functionally significant disease and are most valid for persons from ages 65 to 74 but do not reflect the presence of asymptomatic joint pathology. Standardized physician examinations/assessments would more accurately determine the presence of risk factors in epidemiological studies of musculoskeletal disability.

Comparison of selected health behavior variables in elderly women with osteoarthritis in different environments

Hardiness, social support, perceived health, functional independence, and use of health care facilities were compared in this descriptive study of 45 elderly women with osteoarthritis living in three different environments--urban, rural, and frontier. All participants were between the ages of 65 and 75 years and were residing in their own homes. Statistical differences were found between groups in overall perceived health and functional independence; the frontier sample perceived their health as better and themselves as more functionally independent than the urban or the rural sample. No statistical differences were found in levels of hardiness or perceived social support between the three groups. Use of health care facilities varied among participant groups by environmental context; the urban group made more use of facilities than the rural or frontier group, and the rural group used more facilities than the frontier group.

Aging, comorbidity, and breast cancer survival: an epidemiologic view

This is a review of epidemiologic studies, which suggest that comorbidity (e.g., diabetes and heart disease) has an adverse effect on survival among women with incident, invasive breast cancer, adjusting for chronological age and stage of breast cancer at diagnosis. As part of this review, recent results are presented from a series of 463 breast cancer cases, identified through the Metropolitan Detroit Cancer Surveillance System. Women with two or more concurrent health conditions were 2.2 times more likely than breast cancer cases without comorbidity to die from their breast cancer over a four-year period (95% CI: 1.13, 4.18). Limiting heart disease was especially problematic. Recommendations are made for future research in this area.

Joint impairment and hand function in the elderly

OBJECTIVE

To test the contribution of joint impairment to observed hand function (grip strength and Williams Test) in the elderly, using a multivariate model.

DESIGN

Cross-sectional observational data (baseline data from an ongoing longitudinal study).

SUBJECTS

Five hundred forty-one persons over age 60, including continuing care retirement community (n = 222), homebound (n = 72), and ambulatory (n = 247) respondents. Mean age at assessment 76.7, (SD = 9.0).

MEASUREMENT

Independent variables included sociodemographics, physician measures of upper joint impairment, an index of comorbidities derived from physical examination or chart abstract, self-assessed arthritis pain, depression, and anxiety. The dependent variables included grip strength and a modified Williams Test [Williams Test (M)].

MAIN RESULTS

The multiple regression explained 59% (Adjusted R2 = .59) of the variance in grip strength, with joint impairment accounting for a change in R2 of .07. Upper joint impairment and grip strength accounted for 3% and 5%, respectively, of the variance in the Williams Test (M) (total amount of explained variance = 45%).

CONCLUSIONS

Demographics explain most of the variance in grip strength and performance on the Williams Test (M). Controlling for demographics, musculoskeletal disease represented by joint impairment is associated with diminished grip strength. Reduced grip strength is associated with poorer performance on the Williams Test (M).

Restricted activity days among older adults

OBJECTIVES

The number of restricted activity days experienced by an individual in the course of a year is an important measure of functional well-being, particularly for older adults. We sought to determine multivariate associations between restricted activity days and various health conditions.

METHODS

We used data from the 1984 Supplement on Aging of the National Health Interview Survey to estimate the relationship between restricted activity days and age, gender, and the presence or absence of selected chronic conditions and falls for all noninstitutionalized people aged 65 years and over. Chronic conditions and falls accounted for most of the variance in the model.

RESULTS

Of an annual average of 31 restricted activity days, 6 days were associated with falls; 4 days with heart disease; 4 days with arthritis and rheumatism; 2 days each with high blood pressure, cerebrovascular disease, and visual impairment; and 1 day each with atherosclerosis, diabetes, major malignancies, and osteoporosis.

CONCLUSIONS

These results can be used in estimating the potential impact of health promotion programs on the health status of noninstitutionalized older adults.

Medical expenditures for disability and disabling comorbidity

Disability and disabling comorbidity place a disproportionately large burden on the health care system. National Medical Care Utilization and Expenditure Survey data show that medical care expenditures for noninstitutionalized persons amounted to $154 billion ($691 per capita) in 1980. The medical expenditure per capita for people reporting two or more disabling chronic conditions ($2456) was 5 times the amount incurred by those with no limiting conditions ($486) and more than 1.5 times the amount incurred by those with one limiting condition.

Patient-related predictors of rehabilitation use for community-dwelling older Americans

OBJECTIVE

To determine patient factors that predict use of physical or occupational therapy (PT/OT) services by elderly people.

DESIGN

Time-series study of the relationship of PT/OT use to a variety of characteristics present at baseline.

PARTICIPANTS

Eight-hundred nine community-dwelling men and women aged 65 and older.

SETTING

The Medicare Screening and Health Promotion Trial at UCLA.

MAIN OUTCOME MEASURES

Use of PT/OT services, as reported in a telephone survey 1 year after initial information was obtained on the same subjects by the baseline telephonic survey.

RESULTS

Fifteen percent of the sample used PT/OT within 12 months of baseline. In multiple logistic regression analysis, PT/OT use was significantly less frequent among racial minorities, less well educated groups, and the oldest age group. PT/OT use was higher among those who had both functional disability and the presence of arthritis, heart or lung disease, or a prior history of stroke. However, neither functional disability alone nor the presence of arthritis, cardiovascular or lung disease, in the absence of limited functioning, was associated with PT/OT use. Patients who had obtained a pneumococcal vaccination or used transportation services were also more likely to receive PT/OT.

CONCLUSIONS

Our findings suggest that there may be important sociodemographic inequalities in the use of rehabilitation services and raise the possibility of inappropriate underuse in certain subgroups. Additional studies are needed to determine whether similar inequalities of PT/OT use are found in other populations and whether rehabilitation is effective in various subgroups.

Changing profile of joint disorders with age: findings from a postal survey of the population of Calderdale, West Yorkshire, United Kingdom

A survey of the age-sex specific prevalence of joint problems in a population and associated features such as disablement and use of treatment was carried out in 1986 in Calderdale, West Yorkshire, United Kingdom. A postal questionnaire was sent to 25,168 households; 87% were returned, representing households containing 42,826 people aged 16 years and over. Positive answers to a question about pain, swelling, or stiffness in the joints, neck, or back were given by 10,246 subjects, 24% of the population aged 16 years and older, of whom 6181 (60.3%) were women. The rate of reporting of joint problems increased markedly with age, from 5% for subjects aged 16-24 years to 54% for those aged 85 years and older. The joint sites most often reported as affected were the knee and the back, with a frequency in the population of about 10%. The increase in joint problems with age was accompanied by an increase in reported morning stiffness of more than half an hour, taking drugs, and disability, but not in reporting seeing a specialist for these conditions. Of those aged 85 years and older who reported joint problems, most also had difficulty or dependence in activities of daily living. The increasing prevalence of joint problems with age has implications for the provision of care, both in the community and in hospitals, especially in view of the aging of the population as a whole. The planning of health services for those with rheumatic disorders needs to take into account the high incidence of joint problems in the population.

Labor force participation among persons with musculoskeletal conditions, 1970-1987. National estimates derived from a series of cross-sections

In the present study, we estimated the labor force participation rate among persons with musculoskeletal conditions in 1987, compared this rate with that experienced by persons with other chronic conditions or with none, and estimated the change in labor force participation rates among persons with musculoskeletal conditions for the period 1970-1987. Rates were estimated from 18 years of National Health Interview Survey data, and the sampling weights from this survey were used to obtain population estimates. To ensure statistically stable estimates, we averaged the rates over 6 years of data. In 1987, 42.9% of all working-age persons with musculoskeletal conditions were out of the labor force, this study's definition of work disability. Overall labor force participation rates among persons with musculoskeletal conditions declined from 71% to 56% between 1976-1981 and 1982-1987, 22% in relative terms. Much of this decline was concentrated among men, especially men 55-64 years of age. However, women 55-64 years of age with musculoskeletal conditions also experienced declining labor force participation rates. Labor force participation patterns among persons with musculoskeletal conditions fit more general labor market trends, with gains among younger women more than offset by declines among older men and women. However, these trends appear to be more accentuated among persons with musculoskeletal conditions, suggesting that enforcement of the employment provisions of the Americans with Disabilities Act of 1990 place special emphasis on labor force participation among such persons.

Transitions in health status among community-dwelling elderly people with arthritis. A national, longitudinal study

We used the Longitudinal Study on Aging, a national study of community-dwelling elderly people, to 1) estimate the number of elderly persons with arthritis, with and without other chronic conditions, living in the community in 1984, who reported limitations in physical activities, activities of daily living (ADL), and instrumental activities of daily living (IADL); 2) enumerate the population of the elderly with arthritis who were receiving help or paid help with ADL or IADL; and 3) estimate the number of such persons experiencing a change in health status in the ensuing 2 years. In 1984, 14% of all 15.6 million community-dwelling elderly people had arthritis and no other chronic conditions; 41% had arthritis concurrently with other chronic conditions. Of the former group, 66% experienced limitations in physical activities, but only approximately 25% reported limitations in ADL or IADL in 1984. Among the group with arthritis and other chronic conditions, 82% were limited in at least 1 physical activity, and 41% were limited in ADL. With the passage of 2 years, 2% of elderly persons with arthritis and no other conditions had entered a nursing home, 7% had died, and the percentage reporting no limitation declined significantly. Among elderly persons with arthritis and other conditions, 4% entered a nursing home, 12% died, and the rates of all forms of limitation increased. It is essential to gather data such as these, on the prevalence and incidence of limitation among the elderly with arthritis, to ensure adequate long-term care services for an increasing aged population.