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The Second Fifty Years: Promoting Health and Preventing Disability (1992)

Chapter: Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity

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Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
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14
Social Isolation Among Older Individuals The Relationship to Mortality and Morbidity

Social isolation is considered a risk factor in the development of disease and in the disability that can occur in the course of existing disease. It has been included as well in the measure of quality of life and thus is an outcome as well as a risk factor. A consideration of social isolation almost always occurs in the context of social support, and the two in most cases are used interchangeably. Both concepts have been defined inexactly over the past few decades, and this lack of a standard definition has become more apparent with the increase in the body of work analyzing social isolation as a risk factor for the general well-being of the older population. For this reason, a brief explication and history of these concepts may clarify the definition of this important but sometimes elusive area of interest.

DEFINITION

Social isolation can be defined structurally as the absence of social interactions, contacts, and relationships with family and friends, with neighbors on an individual level, and with ''society at large" on a broader level. The most parsimonious definition of social support is "the resources provided by other persons."11 These resources, which may include emotional, social, physical, financial, and other types of care, cover a broad array of individuals and institutions as the source of this care. Social isolation is defined and then measured by the

Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×

strength of the older person's existing social network and the characteristics of the individuals and institutions providing support to him or her through this network. The absence or weakness of the social support network forms the basis for identifying individuals who are socially isolated. This definition is thus a qualitative one denoting the absence of meaningful relationships. Social support has been used as and continues to be an indicator of the degree of social isolation, and it can serve as the major independent variable in studies of the effect of social isolation as a risk factor of disease or dysfunction. Although the level of social support can serve as well as an outcome variable of quality of life, the discussion here will be limited to its function as a risk factor for health and quality of life.

There is agreement on the overall concept of social support in the body of theoretical work, but an examination of the research reveals inconsistency in both its definition and measurement. An early study32 used a subjective definition, allowing each individual to decide what constituted an intimate relationship. Kahn and Antonucci24 include three aspects of social support in their definition: instrumental or tangible support, emotional support, and agreement with the statements or acts of others. They add an important concept of the "convoy of support," which is intended to capture the dynamic nature of social support as it changes throughout life.

The problems of measurement follow from the problems of definition. A major issue is whether social support is a concept to be enumerated by the quantitative dimensions of the network of formal and informal helpers or whether the focus should be on the quality of the relationships making up this network. A footnote to this dilemma involves the competing concepts of social support as a specific set of observable phenomena that can be identified and replicated or social support as nonobservable and subjective—and therefore different for each individual.

Bruhn and Phillips8 list several factors to consider in measuring the concept:

  1. Environmental and physical factors should be included in addition to social, interpersonal, and cultural factors.

  2. Quantitative aspects should be measured despite the greater ease of focusing on the qualitative aspects of social support.

  3. Social support and health status are more robust indicators when measured together. There is some evidence from prospective studies that baseline assessments of either health status or social support are of little value in predicting subsequent measurements of either variable. If social support and health status result together in

Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×

a more robust indicator, it is a moot point to debate how they might be measured separately.

  1. Social support does not have the same importance or the same components in all cultures.

  2. Social support may vary according to the age and life situation of the individual.

  3. Social support is present in normal as well as in crisis situations.

  4. The reciprocity of social support needs further study.

  5. Community support systems and networks operate and change over time, and more needs to be learned about how they differ according to cultural setting and how members of the community are linked to those systems. Although some of these issues are debatable, particularly in their relevance to studies of risk factors for disease and disability, they reflect the common concerns of researchers in this area.

Bruhn and Phillips8 also list 14 major scales that have been used by researchers to measure social support, categorizing them as including feelings and perceptions, individual functioning, social integration, social participation, emotion, tangible and informational functions, the number of social ties, and the relative importance of these ties. One of the first of these scales to be developed that has had wide use is the Social Readjustment Rating Scale,21 which weights events according to the degree of adjustment each event may require. This approach was used to understand the impact of social support by identifying and quantifying universal occurrences hypothesized as stressors. The sum of the weights for the events experienced by a person for a given period of time constituted the risk for that individual.

Kasl and Berkman27 list several types of indicators of health status that have been used in studies of social support. These include general and specific mortality rates, expectation of life at a specific age, rates of specific morbidity, levels of impairment, indices of disability, and contacts with the health care system. The problems with the measures emerging from this review are several. The data do not reveal which end of the disease spectrum is most influenced by the psychosocial variable in question (e.g., levels of risk factors, onset of clinical disease, gap between onset and diagnosis and treatment, case fatality). In addition, the health consequences of some behaviors may become manifest 20 or 30 years after the individual engages in the behavior. Moreover, the cumulative effect of lifelong practices is rarely explored in studies, and dose-responses or length

Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×

of exposure relationships generally have not been identified. These investigators believe an overriding fault in the field is the assumption of differences among the elderly population and younger populations that have not been documented. Kasl and Berkman consider this belief to be an obstacle to a "dispassionate" examination of the evidence. Consequently, further work must be done to increase standardization of definitions and strengthen measurement.

BURDEN

Prevalence

The few existing studies of the prevalence of social isolation indicate that a total absence of relationships is relatively rare for the elderly.23 Furthermore, when social isolation is identified as a condition of older individuals, the phenomenon is generally accepted as the continuation of a lifelong pattern rather than a development of late life. However, elderly individuals, perceiving themselves to be frail and dependent, may isolate themselves to disguise their loss of autonomy. The limited empirical evidence available on the prevalence of social isolation1,46 seems to corroborate a low prevalence of true social isolation. Theoretical as well as empirical work on the effect of social isolation makes use of social support as an indicator of the degree of social isolation.

Although evidence of total isolation among older individuals may not exist, there has been work suggestive of the existence of relatively low levels of social support for some elderly. In a follow-up study of research involving a community population, 35 percent of the older individuals surveyed reported that they had no confidant (a confidant being defined as someone with whom to discuss serious problems, who was easily available, and with whom there was at least monthly contact).17

Costs

The very early, almost primitive level of definition, measurement, and hence attribution of specific risk to this factor in disease and its outcome is undoubtedly the basis for the lack of estimates of the cost of social isolation, although related areas have been studied. There have been rough estimates made of the cost to families and other care givers for specific diseases, notably Alzheimer's disease;16 in addition, there have been efforts made to analyze the cost-effectiveness of prevention programs for older individuals. The general

Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×

conclusion regarding most of this work is that the methods have not been rigorous and that this area requires the attention of carefully designed and scientifically managed research.2

Impairment, Disability, and Handicap

The theoretical base as well as empirical work on social isolation and disease has not been consistent in differentiating prevention of occurrence (primary prevention) and the various levels of morbidity and mortality (secondary and tertiary prevention). One seminal theory, linking social isolation and resultant stress to weakened host resistance, suggests a nonspecific effect. This tendency is confirmed in the studies reported below on all-cause mortality rates. The studies suggest effects at all stages, pre- and post- impairment, disability, and handicap.

Although specific investigations do not always fit neatly in the various stages of prevention, the work on lack of social support and its effects is a singularly apt illustration of this broader scope in prevention. There have been both empirical investigations and the building of theoretical constructs centering on the strength of social supports in preventing the occurrence of disease, that is, primary prevention. However, much attention has also been focused, particularly for the older population, on secondary or tertiary prevention when the population of interest includes a large percentage of individuals with existing disease. Often, this means a chronic condition that will be a characteristic of the individual to the end of his or her life; therefore, the focus on impairment, disability, and handicap is an appropriate model. In this way a broader, more inclusive strategy can be developed to analyze the effect of social supports (or of any risk factor). The paradigm-like proposition derived from the World Health Organization's (WHO) efforts to achieve standard definitions of disability was used by one of the working groups of the Public Health Service's Health Objectives for the Nation: Year 2000.33 The framework suggested by the group was that of a hierarchy at the disease end of the spectrum of health status, beginning with the development of disease and leading to impairment, disability, and finally handicap, in that order. The positive end of this spectrum begins with independence, leads to productivity, and ends with life satisfaction. This framework is the background against which impairment, disability, and handicap are considered.

The mechanism by which social isolation, one strong source of stress, contributes to morbidity and mortality affords insights into specific outcomes in the course of disease. Much research on social

Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×

isolation points toward a nonspecific effect of this factor on health status. Rahe,35 for example, notes similarities between the nonspecificity of recent life change risk factors and coronary heart disease risk factors, which can come from a variety of sources. Early theorizing regarding causal pathways that link stress to biological changes was pioneered by Cassel.9 He described stress in epidemiologic terms as affecting host resistance and thereby increasing susceptibility to disease. Cassel did not specify the constituents of stress nor identify specific diseases as a result. Rather, he hypothesized a generalized weakening of the host that makes the individual susceptible to insults. Commenting on Cassel's hypothesis, Reed and coworkers37 assert that it is unlikely that specific social processes are inherently stressful to most people in most places and that it is more likely that the individual reacts differently to the situation depending on perception of the situation, personality, prior experience, and means of coping. However, this type of approach would still have consequences for the occurrence of disease and for subsequent impairment, disability, and handicap.

Kasl26 describes the stages of disease subsequent to stress using as a framework the epidemiologic schema that describe the spectrum of health through the natural history of disease development. These stages are as follows: (1) asymptomatic status, risk factor absent; (2) asymptomatic status, risk factor present; (3) subclinical disease susceptible to detection; (4) initial symptom experience; (5) initial event (diagnostic criteria for a disease are met); (6) course of disease; (7) institutionalization; and (8) mortality. He observes that the very broad concepts and general theoretical formulations about underlying processes make it more difficult to identify optimal points in the overall causal matrix at which to consider prevention and intervention.

The state of the art in measurement of social supports has not reached the point where there can be differentiation of the stage of disease at which a lack of social supports has the greatest impact.

Several salient questions illustrate these limitations:

  1. Are the factors that relate to the initial onset of disease the same as those that affect the course and outcome of disease?

  2. How are existing biological risk factors and the structure of social supports representing psychological risk factors related in the overall disease etiology?

  3. Will social isolation or other psychosocial stressors occurring early in life affect outcome in the same manner as they would if they occurred later in life?

Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×

The preceding discussion reflects the early state of the art regarding the role of social isolation in disease. Because of this limited understanding, a precise assessment of the burden occasioned by this risk factor and the potential for prevention is, of necessity, tenuous. An examination of theoretical and empirical work is essential to begin increasing the accuracy of burden assessment. This approach will serve as well as a background for the discussion of preventability that follows.

The role in health of such phenomena as social support and social isolation has its roots in early consideration and theoretical formulation of the mind/body controversy. Despite the hazy and at times unscientific approaches to this area of human functioning, the role of psychosocial concepts in disease and health demands attention. Eastwood described the beginnings of "psychosomatic medicine," which addressed the mind/body paradox, as an attempt to identify psychological variables that promote diseases.15 This early "psychosomatics" movement was reflected in a 1964 WHO report,49 which concluded that the relationship of mind and body was a dynamic one and that the human system can be affected by either psychological or physiological insult and stress. Over the years, and particularly during the 1960s and 1970s, a significant corpus of work emerged in this area.13,20,44

This early, pioneering approach evolved into later large-scale studies to test the role of social supports in mortality and morbidity. This trend began in the mid-1970s and is typified by the studies of House and colleagues,22 Berkman and Syme,3 and Blazer.4 Later research examined prevention strategies designed to delay the onset of disease, affect the early detection of disease, contain the course of functional impairment in the presence of disease, and maintain the highest quality of life in the face of impairments and disability as the result of disease. (This approach clearly addresses all of the stages of the WHO classification and the framework of the Health Objectives for the Nation working group.) The three prospective cohort studies noted above3,4,22 showed higher rates of mortality from all causes for socially deprived older persons. These studies used different measures of social support and varying time intervals over which the effect took place. Yet the analysis in each is convincing in linking the absence of social support to higher mortality rates.

Berkman and Syme3 reported on a nine-year follow-up study of a random sample of 6,928 adults in Alameda County, California. They found that people who lacked social and community ties were more likely to die in the follow-up period than those with more extensive contacts. Their findings also indicated that the "association between

Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×

social ties and mortality was … independent of the self-reported physical health status at the time of the 1965 survey, year of death, socioeconomic status, and health practices such as smoking, alcoholic beverage consumption, obesity, physical activity, and utilization of prevention health services as well as a cumulative index of health practices" (p. 186). Social support in this study was defined as the presence of a spouse, contact with friends, or church and community group membership.

Seventeen-year mortality data from the Alameda County Study were used to examine the relative importance of social ties as predictors of survival at different ages.43 Comparisons of the relative importance of four types of social ties reveal an interesting shift across the age groups. Marital status assumes primary importance for those aged less than 60 years at baseline. However, ties with close friends or relatives assume greater importance for those aged 60 and older.

A study reported by Blazer4 of 331 persons aged 65 and older has a similar finding of a higher death rate among persons who were socially deprived. This effect on mortality occurred over a shorter period—30 months. The measurement of social isolation was based on three factors: roles and available attachments, perceived social support, and frequency of social interactions.

A similar finding of decreased mortality risk associated with higher levels of social relationships was reported by House and coworkers,22 but the finding in this instance was limited to men. The study, the Tecumseh County Health Survey, followed a cohort of 2,754 adults for 9 to 12 years. Trends were similar for women but generally nonsignificant. The measure of social support comprised intimate social relationships, formal organizational involvement outside of work, active and relatively social leisure, and passive and relatively solitary leisure. The findings of these large studies appear to have relevance for each stage of prevention.

There have been other major studies that looked at the relationship of social networks to specific diseases. Haynes,19 for example, examined coronary heart disease using cross-sectional data from the Framingham study. He showed that, for men and women over the age of 65, marital dissatisfaction or disagreements were significantly related to the prevalence of coronary heart disease. This association occurred only for the older age group (aged 65 and older), suggesting that risk factors may change at different ages.27

Reed and colleagues36 reported that prevalence rates for myocardial infarction, angina, and all coronary heart disease were associated with a lack of social network (the study controlled for 12 other

Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×

known risk factors). The associations, however, were with prevalence of disease rather than mortality and thus draw attention to primary prevention. The study population comprised 4,653 men of Japanese ancestry in northern California and a cohort in Honolulu who were taking part in the Honolulu Heart Program. The measure of social support consisted of structural questions regarding the individual's social network: marital status, closeness of parents, number of living children, number of persons in the household, frequency of social activities, frequency of discussing serious personal problems with coworkers, frequency of attendance of religious services, and number of social organizations attended regularly.

Wortman and Conway50 reviewed the literature on social support and recovery from illness, the majority of which constitutes studies of recovery from disease in the hospital. In general, Wortman and Conway found that the effect of social support in recovery from disease is less clear than in longitudinal studies over a long period of time with all-cause disease outcome measures. They note that spurious results can be obtained because of the inability to disentangle socially competent and nonneurotic individuals who may have easier access to social support than less socially able persons and who may be more effective in negotiating the health care system. In spite of these dangers, they believe the majority of interventions provide clear evidence that social support facilitates recovery.

Wallston and coworkers47 believe research evidence supporting a direct link between social support and physical health is more modest than other reviewers have claimed. They categorized studies in terms of the effect of social support on illness onset, the use of health services, adherence to medical regimens, recovery, rehabilitation, and adaptation to illness. (This effort is the most direct parallel to the WHO stages of disability and to various stages and types of prevention.) Wallston and colleagues maintain that these studies fail to distinguish between psychosocial assets as a buffer against the negative health effects of stressful situations and social support as a buffer against illness occurrence. There have been attempts to identify a relationship between social network characteristics and patterns of utilization of health care, but these authors feel the findings from this research are equivocal. In addition, they believe there is evidence for a relationship between social support and adherence to medical regimens. They conclude that there is consistent evidence for positive effects on recovery, rehabilitation, adaptation, and mortality but that it is unclear whether this outcome is due to one type of support or to combinations of support.

Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×

PREVENTABILITY OF BURDEN

Available Interventions

The limitations discussed above addressing specificity of burden and the early developmental stage of research have a direct bearing on an assessment of the range of possibilities for prevention of disease, impairment, disability, and handicap through interventions aimed at the risk factor of social isolation. The literature suggests different pathways between social supports and continuing good health and social supports and the various levels of the outcome of disease once it has been diagnosed. The observations that emerge from past work reflect this dichotomy.

Broadhead and colleagues,7 in their extensive review of social support research, identified concepts inherent in the link between social support and health as well as characteristics of social supports.

  1. Temporality: Poor social support precedes adverse psychological outcomes and mortality.

  2. Consistency: There is a similarity in the direction and magnitude of effect across all major study designs and across a wide variety of age, sex, race, ethnic, and health status groups. However, the effect of social support is greater for women than for men in most studies.

  3. Biological gradient: There is an apparent increase in the numbers of physical and psychological symptoms and mortality with incremental decreases in number and frequency of social contacts. The relationship is less clear for perceived qualitative measures of social support.

  4. Biological plausibility: Experimental evidence (animal and human) suggests neuroendocrine mechanisms, possibly mediated by B endorphin, that might explain both the proposed direct and stress-modifying effects of social support.

  5. Coherence: Social support theory is bolstered by studies in ethology and existing psychosocial theory. Biological evidence can be used to explain the effect of social support in the proposed causal chain between exposure and disease.

  6. Specificity of outcome: The generalized effects on the body of neuroendocrine mechanisms are consistent with the wide number of physical and psychological outcomes associated with variations in social support.

  7. Measurement of exposure: A wide range of definitions of

Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×

social support have been used, many inappropriately, and thus length or depth of exposure is dubiously documented.

  1. Determinants of social support: A large number of environmental and individual characteristics interact to produce a person's social support system at any one point in time.

There are two conclusions that relate directly to intervention:

  1. Experiment/intervention: Social support intervention has improved psychological outcomes of chronically ill children and pregnancy outcomes of women in labor. Otherwise there is a dearth of research adequately evaluating the effect of intervention.

  2. Dynamics of social support: The nature of all these determinants change with sequential role changes and other life events as an individual proceeds through the life cycle.

The evidence thus suggests that lack of social support can play a role in disease and disability and that the existence of strong social support can play a role in sustaining good health as well. Behavioral scientists postulate that the force of social support can be manifested through perceived support inherent in close relationships and through the structure or network of relationships with others. Most researchers12,48 in this area believe social support acts indirectly as a buffer, intervening to protect rather than building up a stronger host. The action of making the host stronger is referred to as ''direct effect hypothesis" by Cohen and Syme11 and postulates that support enhances health and well-being irrespective of the stress level. Langlie31 suggests the effect derives from preventive health practices or the buffer or indirect effect. People with strong social networks will be encouraged and actively assisted in following better health practices, thereby achieving better health and increased longevity.

Bruhn and Phillips8 suggest a paradigm of social support in which a hypothetical dose-response-type curve is postulated under conditions of high or low social support. The ratio of the intensity of stress to duration is plotted against the ratio of the number of illness episodes to a specified period of time. Krause,30 however, found that increases in social support tended to increase feelings of control but only up to a certain threshold. Beyond this threshold, additional support tended to decrease feelings of personal control.

The biological link with social support has attracted a great deal of attention. Recent work by Stein and colleagues45 develops the theoretical basis for the biological link between stress related to social

Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×

isolation and the immune system. In another study, Keller and colleagues28 showed the effect of stress on lymphocyte stimulation in rats and later demonstrated this response in men in the first two months of bereavement.40 The immune system is one of the major integrative networks involved in biological adaptation, and there is evidence that a variety of psychosocial factors influence the central nervous system so that suppression or enhancement of immune functions may result. Braveman6 contends that, in the study of older people, the immune system should be viewed as part of an interactive network of systems whose job is to maintain homeostasis.

Clarification of the difference between intervention to prevent disease occurrence and intervention to reduce the inexorability of impairment from disease leading to disability and handicap is important to help target groups for preventive services. Kaplan and coworkers25 point out a useful distinction at an operational level. Prevention against social isolation relating to primary prevention can be said to involve education and training in coping to teach a person to use social resources to maintain health. Intervention involves training professionals to identify high-risk families and individuals to teach them to manipulate the environment so as to acquire social support. Although this strategy points to different approaches for two target groups, the elderly and the professionals serving them, such intervention can be applied at all levels of prevention—primary, secondary, and tertiary.

Rook39 delineates three levels at which intervention against social isolation may occur: to prevent loneliness, to help the already lonely person establish satisfying interpersonal ties, and to prevent loneliness from evolving into or contributing to more serious problems. Interventions can seek to restructure existing opportunities for social contact or create new opportunities for social contact through network building, thereby bolstering an individual's ability to cope with social loss. One caveat in all intervention studies is that difficult ethical issues may be part of the consideration. For example, when volunteer visits in a Friendly Visitor Program are withdrawn, it may cause stress to the recipient. Schultz and Hanusa42 carried out studies in which residents of a retirement home were given control over the frequency and duration of visits by volunteers. Although these residents showed an initial gain in well-being, after the program was concluded they declined and had poorer adjustment than persons who had not been visited at all.

There are other guides to the nature of intervention for social isolation. Cobb10 organizes categories of support into the instrumental

Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×

support of counseling, guidance toward better coping, active support or nurturing, and material support. Schoenbach41 observes that social support mechanisms are more likely to be strengthened than social stress decreased. If the hypothesized positive impact of social support is upheld, however, a greater lapse of time may be required to observe a true outcome.

Finally, Rodin and coworkers38 propose the following taxonomy of intervention categories based on qualitative differences: (1) cognitive domain (memory, language, and intellectual abilities); (2) social interaction to bolster social support and increase the social interactions of older people; and (3) motivational interventions (changing thoughts and feelings, looking at motivational states). These authors contend that prevention is not merely the alleviation of undesirable states but enrichment in an attempt to optimize function. (This type of approach addresses the upper end of the WHO health scale—away from disease—and presents social support as an outcome indicating life satisfaction.) For the elderly, this enrichment implies malleability of function even as the body ages. Rodin notes four themes that appear repeatedly in intervention studies: plasticity (or the ability to change) within the aging process; between-subject variability in response as well as in status, a phenomenon that appears to increase with age; the concept of control or efficacy or the degree of direction over one's life; and the nature of the intervention and its perceived efficacy.

Effectiveness of Each Intervention

Bloom5 summarized the literature on recent prevention programs in a monograph for the National Institute of Mental Health that was written for the purpose of disseminating and exchanging information on prevention activities. He notes the difficulty of evaluating such programs, especially primary prevention in mental morbidity, and underscores the nonspecific nature of the causal link between concepts of social isolation and social support and disease. Evidence of the effectiveness of prevention programs should be sought by assessing all of the health outcomes that may be affected. This review notes the additional problem of identifying experimental and control groups who have undergone the same stressful life events or set of events and who do not differ significantly on demographic characteristics that are thought to be associated with outcome.

Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×

RECOMMENDATIONS

Services

The dearth of hard data on the most effective and efficient methods for decreasing social isolation and increasing positive social supports has been emphasized. There is, however, a good deal of knowledge on the older population, particularly regarding their use of services, that can serve as a guide when considering strategies for decreasing the risk factor of social isolation. For one thing, it is known that networks of services for the elderly exist in most communities. It is also known that this population makes ongoing, extensive use of medical care34 and that attitudes of the elderly to their physicians have been held to be positive and strong.18 From this combination of "conventional wisdom" and certain established facts, tentative recommendations can be made regarding the role of services in approaches to social isolation.

  1. At-risk individuals must be identified. This process should take place in service delivery sites and should include clinicians as well as other providers. There are indications that the first opportunity for such an identification of needs is at the source of medical care, usually the older person's primary care giver. Other sites include adult protection agencies, home health agencies, senior centers, nutritional settings in churches or schools, and other such locations.

  2. Sources for referral should be identified. Once an individual in need has been identified, a knowledge of sources for referrals is essential. The dissemination of resource information generally is necessary so that family and friends, unattached to formal service-giving, will be in a position to direct attention appropriately to the needy elderly person.

  3. Age-restricted elderly housing developments and retirement communities should begin experimenting with a variety of mechanisms to increase social supports. There are no guides to approaches to isolated individuals because the most successful programs tend to be used by those least in need of aggressive outreach. Very select groups of individuals are found in successful socializing programs in the community,14 which support and enhance the functioning of older people. However, the individuals using such services must be able to attend programs at senior centers and to participate and interact. Thus, they are not necessarily the group for whom services should be a high priority. Whether the methods used in the centers now serving a group of functioning and motivated individuals could

Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×

be adapted to other target groups is an unanswered question. Certainly these services represent a point of departure for planning ways to identify and help socially isolated older people.

Research

The knowledge base for social isolation as a risk factor for disease, for functional incapacity in general, and for disability and handicap as a result of that incapacity is in an early, even primitive stage when compared with knowledge regarding the risk of smoking, the importance of dietary control, and other more directly observable and more thoroughly researched areas. However, the work to date provides sufficient evidence of the serious consideration commanded by social isolation as a risk factor. Much depends on continuing delineation of research questions and intervention evaluations. Crucial questions have been raised earlier that shape priorities in research. The basic questions on age differences for this risk factor, for example, and the designation of the point at which preventive services can be of greatest benefit to an older population are two of the unanswered questions that are most important in clearly identifying appropriate target groups as well as appropriate interventions. The question of "directionality" must also be addressed; that is, do ties and support diminish, remain constant, or increase when older individuals become ill, and under what circumstances? Basic issues of definition, measurement, and causal relationships are generic types of research that parallel these more specific issues.

The committee recommends that the following questions, posed by Kiesler,29 be addressed as high-priority research areas:

  1. Does social support reduce stress in ways that can be objectively measured and that are socially desirable?

  2. Is the effect causal?

  3. Which type of support is most effective: self-help groups, professional intervention, or the strengthening of relationships of family and friends?

  4. If most effective support sources are identified, what are the ways to increase such support to large populations?

  5. What are the characteristics associated with differences in the amount and type of social supports that are available and used?

  6. Does the current style of service facilitate or interfere with increasing social support?

  7. Does social support have similar effects on physical and mental health?

Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×

The answers to these questions constitute designs for a variety of research projects, which require careful construction to parallel each of the areas that have been identified (definition, measurement, relationship to health and disease). This research should be integrated into experimental, targeted intervention studies for reducing the risk factor of social isolation and for examining the effects of doing so.

Education

Education as part of an overall strategy in reducing social isolation, to be most effective, must be aimed at three populations: providers of care, including clinicians; other care givers such as families, friends, and neighbors of older individuals who may be isolated or poorly supported; and the elderly themselves.

Providers
  1. All health care providers should be educated in the importance of strong social supports.

  2. Providers should be trained in methods of identifying those at high risk.

For providers of care, methods of identifying at-risk individuals and information on existing resources are probably the most efficacious means of attacking this problem. Unless the support falls within the particular purview of the specific service being rendered, education in providing direct support may be inefficient in the case of physicians. Rather, clinician education should focus on the importance of social supports and methods of identifying those at high risk. Following identification, it will be necessary to find appropriate services and transmit knowledge of how to use such services.

Families
  1. Strategies should be developed to provide information about the social needs of elderly family members.

  2. Strategies should be developed to provide information about available resources and access to their use.

For families, information about the problem, wide dissemination of information regarding available services, and the motivation to

Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×

make use of such services constitute a strong educational approach to reduce this risk factor. The problem in this case may be circular in that those most in need of such services are the least likely to have families, friends, and neighbors, or others with sufficient concern to take action. A general campaign to provide information about social needs and resources with easy access to meet those needs is one possible approach to this problem.

The Elderly

The majority of elderly persons know the importance of a social network. The committee recommends that educational resources be developed to attract and then inform them of available resources.

Education of the elderly themselves parallels comments on educational efforts for the first two groups. It would be disingenuous to presume that people are isolated because they do not know that it is important to have a support network. How the elderly are educated in this matter requires careful investigation using various strategies to attract and then educate a group in need. There have been investigations and demonstrations with older individuals along a broad spectrum of psychosocial needs and activities. This past work requires consideration, plus specific recommendations and trials to establish the best way to proceed.

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Suggested Citation:"Social Isolation Among Older Individuals: The Relationship to Mortality and Morbidity." Institute of Medicine. 1992. The Second Fifty Years: Promoting Health and Preventing Disability. Washington, DC: The National Academies Press. doi: 10.17226/1578.
×
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Taking its title from the second 50 years of the human life span of about 100 years, this book presents wide-ranging and practical recommendations for health care providers, policymakers, and other sectors of society. These recommendations range from setting new national policies to changing the way elderly patients are interviewed in the doctor's office and from what exercises older persons should do to how city planners should design our urban environment.

The bulk of this volume presents the latest research on 13 major health threats to the elderly, covering prevalence, impact on the older person's life, cost, and intervention.

In addition, the authors provide a detailed analysis of why older people often do not receive the benefit of prevention programs.

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