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This field of investigation has employed many of the standard
epidemiologic designs (e.g., case-control, cohort, cross-sectional, and
experimental designs). For example, the role of stress in health
outcomes is one of the major concerns of psychosocial epidemiology.
Some of the earlier research studies on this topic used cross-sectional
investigations of captive and readily available populations (e.g., workrelated groups of white male professionals). At present the research
community acknowledges the importance of including diverse study
populations in epidemiologic investigations. Cross-sectional studies of
psychosocial factors in health are attractive because of the relative
ease of such research. Cross-sectional designs, however, may not be
adequate to detect the subtle effects associated with psychosocial
factors, especially the issues of temporality of cause and effect and
the influence of confounding variables.
Also needed are more longitudinal, prospective studies of the role of
psychosocial factors in health as well as studies of women and
minority groups, although much progress has been made in
developing these types of studies in recent years. Among the many
excellent initiatives in this area is the work of investigators in
Germany.6 Researchers, conducting the Early Developmental Stages
of Psychopathology study (EDSP), began data collection in 1994–
1995. The EDSP was a prospective study of adolescents and young
adults who resided in the city of Munich, Germany. A total of 3,021
adolescents and young adults aged 14–24 years were included at
baseline. Subjects were followed up on average after a 42-month
interval. This project has made possible the study of the incidence of
various mental disorders, including the general anxiety syndrome and
depression.7,8 See Figure 15–2 for information on the data collection
intervals for the study and the types of information collected.
A unique challenge of psychosocial studies is to obtain valid and
reliable operationalization of measures. The process of
operationalization refers to the methods used to translate some of the
concepts employed in psychosocial epidemiology into actual
measurements. For example, much controversy surrounds the
development of measures of stress, epidemiologically useful
measures of mental health, and measures of social support. In
addition, as part of the process of improving measures used,
epidemiologists need to develop well-delineated conceptual models of
psychosocial processes.
FIGURE 15–2 Early Developmental Stages of Psychopathology
Study.
Source: Courtesy of Roselind Lieb, Basel, Switzerland, and Hans-Ulrich Wittchen,
Dresden, Germany.
Community-based participatory research (CBPR) is a methodology
with much relevance to psychological and social epidemiologic
studies. CBPR can be thought of as an alliance between community
organizations and research units (e.g., universities or research
centers) in order to investigate health-related issues of interest to the
community. Many of the personnel affiliated with research units have
had formal training in research methodology. The community
organizations have an investment in health issues that affect the
members of the community. The organizations can facilitate access to
members of the community in order to collect research data. These
complementary skill sets help to improve the quality of information that
is gathered in research projects. CBPR results in the eventual training
and empowerment of community organizations to conduct their own
independent research projects that address their unique needs. Figure
15–3 shows members of a community meeting organized by the
Agency for Toxic Substances and Disease Registry
An example of CBPR is an epidemiologic study of tobacco use among
the Cambodian community of Long Beach, California. A research
team organized by Robert Friis collaborated with a community
organization in Long Beach in order to study sociocultural factors
associated with Cambodian Americans’ use of tobacco. Cambodian
American men have a higher prevalence of cigarette smoking than
other groups in California.9
FIGURE 15–3 Town hall meeting held on behalf of the Agency for
Toxic Substances and Disease Registry.
Source: Reproduced from Centers for Disease Control and Prevention. Public Health
Image Library. Image number 11619. Available at http://phil.cdc.gov/phil/. Accessed
May 2, 2012.
The Social Context of Health
Interest in the role of the social environment in health has flourished in
recent decades, perhaps because epidemiologists have recognized
that the social environment may contribute to the regulation of
psychosocial influences upon health. As noted previously, the social
environment is the totality of the behavioral, personality, attitudinal,
and cultural characteristics of a group of people. The social
environment provides the context in which psychosocial factors
operate.
An example of the potential social influence of the social environment
on health comes from Scotland, which has higher mortality than
England and other European countries.10 A possible explanation is
that this outcome is due to higher levels of deprivation in Scotland.
However, these mortality differences persist when the level of
deprivation (e.g., lack of car ownership, overcrowding, male
unemployment, and social class) is controlled. The term Scottish
effect signifies excess mortality in Scotland after controlling for the
effects of deprivation. Excess mortality in the West of Scotland
(Glasgow) after controlling for deprivation is called the Glasgow effect.
When deprivation levels are controlled in Glasgow and the relatively
close cities of Liverpool and Manchester, excess mortality in Glasgow
can still be observed.
The Social Context and International
Comparisons
From the population perspective, we find that the social environment
impacts the health of residents of both the less-developed and moredeveloped worlds.11 In less-developed regions, life expectancy is
reduced in comparison with the developed world due to the impact of
poverty, with its attendant malnutrition and infectious diseases.
Overcrowding, poor living conditions, and lack of preventive health
care foster the spread of infectious diseases. Figure 15–4 was taken
during the 1970s in Bangladesh during the World Health
Organization’s smallpox eradication program. The image shows an
impoverished man begging for money in order to provide food for his
unclothed child.
The social environment is also an influential component of the major
causes of morbidity and mortality through the impact of noninfectious
conditions, which are the leading causes of death in the developed
world. Lifestyle factors—smoking, diet, insufficient exercise, and use
of illegal substances—undoubtedly play a role in the etiology of many
of these conditions. A noteworthy example is the reduced life
expectancy in the countries of central and Eastern Europe and the
former Soviet Union in comparison to the European Union countries.
Some authorities have suggested that one of the contributing factors
to this reduction in life expectancy is excessive alcohol consumption,
although the influence of alcoholism on life expectancy is by no means
clear-cut.11
FIGURE 15–4 A village in Bangladesh in the 1970s during a
campaign to eradicate smallpox from the country.
Source: Reproduced from Centers for Disease Control and Prevention. Public Health
Image Library. Image number 7405. Available at http://phil.cdc.gov/phil/. Accessed May
2, 2012.
In order to compare accurately among nations the contributions of
disease to morbidity and mortality, work has proceeded on the
development of measures that could be used in all countries. The
Global Burden of Disease Study attempts to quantify and provide an
epidemiologic assessment of the worldwide consequences of disease
by using a measure known as the disability-adjusted life year (DALY)
to assist in comparisons across countries.12 The DALY is a statistical
measure applied to populations that combines information on mortality
with information on morbidity for specific causes. The advantage of
DALYs is that they provide a standard epidemiologic unit for
comparative purposes. According to Murray and Lopez, “The 10
leading specific causes of global DALYs are, in descending order,
lower respiratory infections, diarrhoeal diseases, perinatal disorders,
unipolar major depression, ischaemic heart disease, cerebrovascular
disease, tuberculosis, measles, road-traffic crashes, and congenital
anomalies. [A total of] 15.9% of DALYs worldwide are attributable to
childhood malnutrition and 6.8% to poor water and sanitation and
personal and domestic hygiene.”12(p 1436) The social environment
contributes to many of these DALYs via a range of pathways including
unsanitary living conditions associated with crowding; discrimination
and social exclusion; low status on the social hierarchy; social
isolation; and adverse lifestyle choices.
The Whitehall Study
First Whitehall study–initiated in 1967, the first Whitehall study
covered 18,000 men in the British Civil Service. Among its findings
were a higher likelihood of premature death among the lowest
employment grades; these socioeconomic inequalities were not
explained by standard risk factors (e.g., smoking).
Whitehall II study–noted social epidemiologist, Sir Michael Marmot,
began the study in 1985. Participants were 10,308 nonindustrial civil
servants from 35 to 55 years of age; approximately one-third of the
sample was composed of women. “Whitehall II data have been used
to build one of the most detailed pictures of the determinants of health
in mid-life and late-life.” One of the important contributions of the study
has been to highlight “… the importance of psychosocial factors such
as work stress, unfairness, and work-family conflict to socio-economic
inequalities.”
Source: Whitehall II History. http://www.ucl.ac.uk/whitehallII/history. Accessed August 8,
2012.
A Landmark Study on the Effects of
Socioeconomic Inequalities
A major research program on socioeconomic inequalities in health is
the Whitehall study conducted in Britain. (Refer to the text box titled
The Whitehall Study).
Independent Variables
In addition to the social environment, we will now consider how the
major categories of psychosocial variables listed in Figure 15-1 affect
health outcomes. Examples of independent variables covered in
psychosocial epidemiologic research include general concepts of
stress, social incongruity theory, person-environment fit, and stressful
life events.
General Concepts of Stress
According to a classic definition, psychological stress is “… a
particular relationship between the person and the environment that is
appraised by the person as taxing or exceeding his or her resources
and endangering his or her well-being.”13 Societal structures,
interpersonal processes, and the individual’s physiological, cognitive,
and other responses relate to the distribution of stress. Stress as an
independent, antecedent variable to health and illness represents an
intriguing notion because it seems to support common sense
explanations for the cause of some mental disorders, sudden death
due to heart attacks, and other chronic conditions. Also, researchers
have argued that stress induces physiological changes such as
alterations to the immune system. When environmental demands
challenge an organism (e.g., experimental animal or person),
homeostatic regulatory mechanisms help the organism to maintain
balance among essential biological functions. Homeostasis refers to a
tendency toward a stable equilibrium among physiological processes.
Allostasis denotes “… how the organism achieves stability (or
homeostasis) through continual change.” 14(p 36) The term allostatic
load “… refers to the consequences of sustained activation of primary
regulatory mechanisms serving allostasis over time …” 14(p 36) One’s
allstatic load is hypothesized to be associated with disorders and
adverse health outcomes.
Many aspects of contemporary life are stressful as a result of
economic forces, the changing nature of employment, and other
environmental and social factors. Economic stresses due to
unemployment, banking collapses, and the increased
cost of living are prominent features of modern existence worldwide.
In the United States the violent consequences of stresses experienced
in the workplace (e.g., “going postal”) are a common topic of media
reports. Figure 15–5 shows a poster designed for an employee
assistance program operated by an occupational medical service. The
program targeted workers under stress due to their self-perceived
inability to meet the demands of their job.
The scientific evidence for stress as an etiologic agent of disease is
both controversial and contradictory. A review of the numerous
writings on stress leads one to conclude that the concept has more
than one meaning and that some of the meanings tend to be vague or
inconsistent. The concept of stress has a venerable historical
background in the field of medicine and in other disciplines, but it is
often regarded with scientific skepticism. However, many research
findings have tended to support the stress concept. For instance,
Walter Canon’s classic research studied changes in gastrointestinal
function that accompanied stressful events, such as pain, hunger, and
major emotion.15 (Refer to Figure 15–6 for Canon’s image.) The late
Hans Selye,16 shown in Figure 15-7, specified in detail the stages of
reaction to stress through the concept of the general adaptation
syndrome. Selye conceived of stress as a change in the environment
of the organism and proposed that the organism’s response consisted
of three stages: alarm reaction, stage of resistance, and stage of
exhaustion. Activation of the general adaptation syndrome, associated
with corticoid secretion, may produce somatic disease (e.g.,
mineralocorticoid hypertension [hypertension caused by excessive
activation of mineralocorticoid receptors] and cardiac necrosis [death
of cardiac tissue]).17
FIGURE 15–5 A poster designed for an employee assistance
program operated by an occupational medical service.
Source: Reproduced from National Library of Medicine. Images from the History of
Medicine. Order account number: C01097. Available at:
http://ihm.nlm.nih.gov/images/C01097. Accessed September 1, 2012.
FIGURE 15–6 Walter B. Cannon, 1871–1945.
Source: Reproduced from National Library of Medicine. Images from the History of
Medicine. Order account number: C01097. Available at:
http://ihm.nlm.nih.gov/images/B04183. Accessed September 1, 2012.
FIGURE 15–7 Hans Selye, 1907–1982.
Source: Courtesy of the Hans Selye Foundation.
Selye’s Concept of the General Adaptation
Syndrome
1. Alarm reaction: physiologic responses associated with
preparation to deal with stress that lead the animal or person to
fight or escape from the stressor.
2. Stage of resistance: return of physiologic responses to normal
and resistance to further stressful stimuli.
3. Stage of exhaustion: failure of the organism to adapt to
overwhelming stresses. “Adaptation energy” becomes
exhausted, and, in the case of humans, severe bodily disease
and death may result.
According to some experts, stress research refers to a broad area that
explores how aversive environmental events control multiple response
systems (verbal, physiological, and behavioral).18 Clinical findings
suggest that these aversive events produce negative health
outcomes. Three examples of aversive events that may produce
stress responses are presentation of noxious or biologically damaging
stimuli (either by actual presentation or threat of presentation),
removal of reinforcements (either actual or threatened), and conflict
situations. An example of a presentation of damaging stimulus is
electric shock experimentation. The early executive monkey
experiments demonstrated that physiologic arousal linked to
behavioral responses to remove the threat of electric shock was
associated with gastric ulcer in monkeys.18 Removal of a positively
reinforcing stimulus includes removal of rewards, such as those
associated with good behavior, and environmental supports. Removal
of positive reinforcements may be associated with impaired mental
health and other illnesses. Finally, a conflict situation is one that
generates two or more incompatible responses in the same individual.
Examples are attitude conflicts, role conflicts, and conformity conflicts,
the last of which was associated with changes in lipid metabolism in
one experiment.18
Social Incongruity Theory (Status
Discrepancy Models)
Social incongruity is defined as a situation in which the individual is
not in harmony with or is incompatible with other persons; it can also
denote lack of harmony between the individual and the larger society.
Social incongruity can occur among the following: friends and
significant others, a person and place of residence, members of
different generations, and a foreign-born person with native-born
residents. Status discrepancy refers to disharmony that arises from
differences among the statuses of individuals (e.g., among higher- and
lower-ranked persons within society).
Investigators have hypothesized that both social incongruity and
status discrepancy are associated with adverse physical and mental
health outcomes. General themes of research have included changes
in residence from one country or culture to another, changes in
residence from a rural to an urban area, upward intragenerational
mobility, and marital status stress (i.e., discrepancy between husband
and wife in social and educational status).
The late Sidney Cobb and associates compared women who were
afflicted with rheumatoid arthritis (RA) with women who were not so
afflicted. Women with RA were more likely to originate from homes
with high parental status stress, defined as discrepancy between
parents with respect to indicators of social status. An example was a
mother of high social status married to a father from a background of
lower social status. Interestingly, married women who had RA also
tended to be immersed in marriages that had high status stress.19 In
another study related to status stress, Shekelle and colleagues20
noted that risk of new coronary disease among men in a prospective
study was associated with discrepancy between their social class at
the time of the study and either their own or their wives’ social class in
childhood.
Syme and coworkers,21 in research using urban male subjects from
the California Health Survey, reported that cultural mobility was
associated with CHD. Cultural mobility was defined as moving from
one social setting to another or remaining stable within a given social
setting while the setting itself undergoes change. In a case-control
study, Syme et al. operationalized cultural mobility as cultural
discontinuity and occupational mobility. Among male progeny of
foreign-born fathers, sons who had college-level education had
observed-to-expected (O/E) CHD ratios that were five times higher
than those of sons who had completed only grade school or high
school. Among college-educated men, sons of foreign-born fathers
had O/E CHD ratios that were more than two times higher than those
of sons of native-born fathers. Regarding occupational mobility,
men who held three or more different jobs for brief time periods during
their lifetimes had O/E CHD ratios that were four times as high as the
ratios of those who held only one or two jobs. Thus, in an urban
setting, Syme et al. replicated findings regarding cultural mobility and
increased CHD risk observed previously in rural areas.21
The Person-Environment Fit Model
The late John French and associates defined person-environment fit
“as the goodness of fit between the characteristics of the person and
the properties of [his or her] envir …
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