Description/Samples/Epidemiologic Evidence

PSYCHOLOGICAL STRESS

o Stress model (Herbert & Cohen, 1996):
Environmental demands (major life events, daily events, chronic strains) *
Psychological appraisal (perceived stress) *
Emotional responses *
Biological (cardiovasular, neuroendocrine, immunologic) & behavioral responses *
Increased risk of disorder.

o While measuring all 3 components of stress process (environmental demands, psychological appraisal, & emotional response) is necessary to elucidate mechanisms regarding the role of stress in psychiatric & physical disorder (Herbert & Cohen, 1996; Vedhara K et al., 2000), the Healthy Brain Initiative may wish to focus on measuring perceived stress, an area that has been relatively neglected in comparison to the measurement of environmental demands and emotional responses.

o There is great heterogeneity in the conceptualization of stress response, with investigators using indices of anxiety, depression, stress, or a combination of these (Vedhara K et al., 2000).

o Only checklist/questionnaire measures are listed below.

     o Interview measures such as the Life Events and Difficulties Schedule (LEDS; Brown & Harris, 1978) or the Structured Event Probe and Narrative Rating (SEP-RATE; Dohrenwend et al., 1993), are not considered, as such measures may not be appropriate for use in large-scale epidemiologic settings.
     o Single-item questions designed to measure evaluations of specific stressful events are not considered. Such questions are commonly used in lab experiments or in studies of events using daily diary designs.

A. ENVIRONMENTAL DEMANDS

1. MAJOR LIFE EVENTS

a. Measures

i. Social Readjustment Rating Scale (SRRS; Holmes & Rahe, 1967; Miller & Rahe, 1997).

43 items. Users implicitly assume that amount of stress is determined by cumulative amount of change or readjustments brought about by events occurring in one's life. Note: Miller & Rahe (1997) rescaled the 43 original events & added 44 new events to create an updated scale.

o Thomas SA et al. (1997). Cardiac arrhythmia suppression trial (CAST). 348 patients w/asymptomatic ventricular arrhytmias after MI. Among men in non-active medication group, "more past life events & lower expectations of further life events" (as assessed with SRRS) were associated with higher mortality.

ii. Psychiatric Epidemiology Research Interview for Life Events (Dohrenwend et al., 1978)

o Rosengren A, Orth-Gomer K et al. (1993). Gothenburg Study. Pop'n based sample of 752 50-yr old men followed for 7 yr. Life events (10 items from PERI) are associated with higher mortality.

o Monroe SM et al. (1991). Stress (measured by PERI) affects time lag between onset of depression & time to treatment entry.

iii. Geriatric Social Readjustment Rating Scale (Amster & Krauss, 1974)

Consists of events judged to be of particular relevance to the elderly by a panel of gerontologists.

o Cutrona et al. (1986). Scores on this scale are related to physical & mental health.

o Vedhara et al. (2000). 50 spousal caregivers of dementia patients, followed for 6 months, used this scale.

b. Bereavement, a specific major life event.

o Martikainen & Valkonen (1998). Prospective study of all married Finnish persons aged 35-74. Education & income buffer effect of death of spouse on mortality to some extent. While relative mortality after death of spouse was similar in different SES groups, absolute mortality differences between bereaved & nonbereaved persons were larger in lower SES groups.

c. Epidemiologic findings

o "A substantial preponderance of the now massive literature assessing the linkage between social stress & health is based upon checklist measures of life stress" (Cohen et al, 1995, p. 30).

o Do life events checklist measures predict disorder? There are reliable associations between life events & the occurrence of psychological distress, and, to a lesser extent, clinical disorders, including psychological disorder, coronary disease, infectious, & allergic & autoimmune diseases. Magnitude of associations has been moderate at best. Possible reasons include:

     o Event lists are not comprehensive
         o selectively emphasize events of young adulthood
         o omit events common among the poor & certain racial/ethnic groups
         o omit common but socially sensitive events (e.g. marital infidelity)
         o omit nonevents
     o Event weighting, valence of events
     o Timing of events & onset of disorder unclear

o Confounding: Personality traits may be viable explanations for event-disorder associations

o Melamed S et al. (1997). Cardiovascular Occupational Risk Factors Determination in Israel Study (CORDIS). 1859 male workers. "Life events (what measure?) were negatively associated with systolic and diastolic BP, triglycerides, and uric acid . there was a linear trend between intensity level of life events and low exercise, smoking, and alcoholic intake."

o Rose G et al. (1998). Renault/Volvo Coeur Study. 1000 male workers. Negative life events (what measure?), especially work-related, were associated with depressed mood & mental strain but not with elevation of biologic RF such as elevated BP & serum lipids.

2. DAILY EVENTS

a. Measures:

(i) Hassles Scale (DeLongis, Folkman & Lazarus, 1988). 53 items. Assess events retrospectively over 1-month period or on a daily basis.

(ii) Inventory of Small Life Events (Zautra et al., 1986). 178 items. Assess events retrospectively over a 1-month period.

(iii) Daily Life Experiences Checklist (Stone & Neale, 1982). 78 items. Assess events on a daily basis.

d. Daily Stress Inventory (Brantley & Jones, 1989; Brantley et al., 1993). 58 items. Assess events on a daily basis. Brantley et al. explores convergence between this measure & endocrine measures of stress.

b. Epidemiologic/other evidence:

o Daily events scales are not used much in epidemiology.

o There is little evidence on the ability of daily hassles to predict hard physical health outcomes.

o Reporting more daily events is related to reports of daily negative mood (Stone & Neale, 1982), to concurrent & future reports of increased psychopathological symptoms (Eckenrode, 1984; Monroe, 1983), as well as increased demoralization & distress, & decreased well-being & QOL (Zautra, Guarnaccia, & Dohrenwend, 1986). Daily events are also related to increased physician use (Gortmaker et al., 1982), reduced WBC (Kubitz et al., 1986), higher blood glucose among diabetics (Cox et al., 1984).

3. CHRONIC STRAINS

Chronic strain self-report measures tap perceptions & attitudes about potentially stressful aspects of social conditions & roles. Most measures are domain specific. Domains receiving the most attention are work, marital, & caregiving areas.

a. Measures

(i) Work (See Demographic & Psychosocial Measures document)

(ii) Marital. Items typically relate to communication problems, verbal/physical abuse, lack of emotional closeness, sexual problems, excessive role demands, inequities in division of labor or decision-making processes.

     (a) Family Environment Scale (Moos & Moos, 1981)

     (b) Marital Situations Inventory (MSI; Smolen et al., 1985)

     (c) Marital Agendas Protocol (MAP; Notarius & Vanzetti, 1983)

(iii) Caregiving

     (a) Burden Interview (Zarit & Zarit, 1990)

    o Vedhara et al.(2000). 6-mo study of chronic stress among 50 caregivers, used this scale.

See also:

o Schulz R, Beach SR. (1999). Caregiving as a risk factor for mortality: The Caregiver Health Effects Study (a substudy of Cardiovascular Health Study), & accompanying editorial by Kiecolt-Glaser & Glaser.

b. Epidemiologic evidence:

o In general, chronic strain questionnaires have not been shown to predict objective health outcomes in a consistent manner (but see "Occupational Stress", next section).

o As with checklist measures of life events & daily events, enduring mood states or stable personality characteristics may lead an individual to recognize & recall more chronic strains, report more strains, experience more strains, & report higher rates of disorder.

o Cause & effect unclear. Issue of items being confounded with outcomes is an important one. Items asking about interpersonal conflicts, work overload, or lack of emotional closeness might largely reflect psychological distress.

B. PSYCHOLOGICAL APPRAISAL

Stress occurs when individuals perceive that environmental demands exceed their coping abilities (Lazarus & Folkman, 1984). Researchers interested in appraisal ask whether the feeling of being stressed contributes to psychological or physical illness. [Comment: The major problem in studies of the relationship between stress & psychological disorder is the potential of confounding of appraisals with various antecedents of appraisals as well as with the psychological outcomes of interest. Personality, psychopathology, cognitive styles, beliefs, values, & current mood state all affect appraisal & reporting of stress & may independently influence vulnerability to disorder (Aldwin et al., 1989). The question is whether appraisal is a reflection of underlying processes that are themselves responsible for incurring vulnerability or whether appraisal is the determinant of vulnerability directly. Cohen suggests that future studies incorporate measures of antecedents & components that contribute to appraisal so that competing views of the role of appraisal in the stress process can be assessed.]

1. Measures:

a. Perceived Stress Scale (PSS; Cohen et al., 1983; Cohen & Williamson, 1988)

Measures degree to which subjects find their lives to be unpredictable, uncontrollable, & overloading - i.e., measures a global appraisal, a response to cumulative total of life stressors facing an individual. Original scale had 14 items; the more recent 10-item version is the one recommended for use. (See Cohen's website.)

o Recent studies show prospective associations between PSS & many psychiatric & physical illness outcomes. Cohen's research has demonstrated that PSS scores predict various outcomes independent of measures of psychological & physical symptoms assessed at baseline.

o Cohen, Tyrrell & Smith (1993). Perceived stress (PSS) prospectively predicted susceptibility to infection with common cold viruses.

o Glaser R, Kiecolt-Glaser JK et al. (1999). Women with higher perceived stress (PSS) had delayed wound healing.

o Normative Aging Study uses PSS.

o Vedhara et al. (2000). 6-month study of caregiver stress used PSS.

b. Perceived Stress Questionnaire (Levenstein S et al., 1993)

30 items, validated in 230 subjects. General (past 1-2 yrs) and recent (past month) scores available. This measure may be a valuable addition to the literature, but has not been widely used.

c. Stress Appraisal Measure (SAM; Peacock & Wong, 1990)

An example of a measure of a specific stressor & associated appraisals.

C. EMOTIONAL RESPONSES

Environmental demands appraised as stressful are thought to influence risk of disorder through negative emotional responses. Although this association is commonly accepted, unanswered questions about emotion's role in the stress process include: Are emotional responses necessary for events & appraisals to exert effects on behavioral, psychiatric & physiological processes? Do short-term emotional reactions have the same biological impact as longer-term reactions? Are acute bursts of emotion particularly disruptive to psychological & physiological function?

1. NEGATIVE AFFECT

Measures (See also Depression, Anxiety, Multidimensional sections):

a. Nowlis Mood Adjective Checklist (MACL; Nowlis & Green, 1957).

12-item & 36-item versions. 36-item version has 12 factors: aggression, anxiety, surgency, elation, concentration, fatigue, social affection, sadness, skepticism, egotism, vigor, nonchalance.

b. Profile of Mood States (POMS; McNair et al., 1971).

65-adjective checklist that asks subjects to rate how they felt during past week (could also be used "today", "right now"). Six factors: tension-anxiety, depression-dejection, anger-hostility, vigor-activity, fatigue-inertia, confusion-bewilderment. Originally called "Psychiatric outpatient mood scale."

c. Differential Emotions Scale (DES; Izard et al., 1974).

Shorter measure than Nowlis or POMS. Several versions; all measure 10 emotions: joy, surprise, sadness, anger, disgust, contempt, fear, shame/shyness, and guilt. Each adjective is rated on a multipoint scale for how the subject currently feels.

d. Positive and Negative Affect Schedule (PANAS; Watson et al. 1988).

Assesses positive & negative affectivity. PA and NA are each assessed by 10 items. Scores on the two dimensions are relatively independent. PA adjectives: attentive, interested, alert, excited, enthusiastic, inspired, proud, determined, strong, active. NA adjectives: distressed, upset, hostile, irritable, scared, afraid, ashamed, guilty, nervous, jittery. Subjects rate the extent to which they feel each emotion on a 5-point scale. Timeframe can vary from "right now" to "past year" to "on average."

o Glaser et al. (1999). "General negative affect" (PANAS) is related to low cytokine production.

e. Grief Measurement Scale

o Priegerson HG, Bierhals AJ, Kasl SV, et al. (1997). 150 future widows/widowers interviewed at time of spouses' hospital admission & at regular intervals up to 25 months later. Traumatic grief following bereavement was measured with Grief Measurement Scale. "Presence of traumatic grief after death of spouse predicted such negative health outcomes as cancer, heart trouble, high blood pressure."

2. REACTIVE RESPONDING

Reactive responding = "the self-regulatory patterns believed to develop as a result of exposure to chronically stressful environments that may increase as one is lower on the SES ladder" (Taylor & Seeman 1999, for MacArthur SES & Health Psychosocial Working Group)

The lower one's social class, the more likely one's environments (family, school, work, neighborhood) lack resources (e.g. time & money) and are higher in chronic stressors (e.g. crowding, noise, crime). Conversely, the higher one's social class, the more likely one's environments are richer in resources & lower in chronic stressors, providing opportunities for development of self-regulatory skills devoted to setting future goals, planning, developing a future temporal orientation, etc. Regularities across environments within level of social class may produce fairly stable class differences in prevailing modes of responding, such that, through chronic use, such self-regulatory mechanisms become instilled as habits or dispositions, & thus may be employed in new environments where they may not always be maximally useful.

Characteristics of reactive responding:
o Chronic vigilance/load: A high level of environmental demands, coupled with danger or urgency, may lead to a state of chronic vigilance, such that individuals constantly monitor the environment for threatening cues.
o On-line responding/on-line planning: When individual action is driven by environmental demands rather than a self-generated agenda, there may be little opportunity for anticipatory planning; rather, what planning does occur may be on-line in response to environmental demands.
o Emotional reactivity: Responding in demanding environments may be emotionally charged due to environmental interruptions, environmental risks, & absence of personal control.
o Constrained options: When responding occurs as a result of environmental demands rather than self-generated planning, environmental options may be few, & the opportunity for a person to develop alternatives may be low.
o Narrow learning & skill development: To the extent that environmental demands drive a person's responses, there may be few opportunities for broad learning. Within the context of constrained options, learning & skill development may be narrow.
o Present orientation: High levels of environmental demands & the need to respond reactively to an environment may foster a present orientation that keeps a person focused on the short-term future.
o Simple, short-term goal orientation: A focus on the present, a relative absences of resources, and a relative dearth of opportunities for individual control may lead to development of simple & short-term goals, rather than creation of long-term goals & opportunities.

o MacArthur reactive responding scales (Taylor & Seeman 1999). Developed by MacArthur SES & Health Psychosocial Working Group. Long form contains 7 scales (constrained options, emotional reactivity, goal orientation, load, narrow learning, present orientation, vigilance); each scale contains 6 items. Short form includes 3 scales (emotional reactivity, goal orientation, vigilance); each scale contains of 3 items. Item examples. Emotional reactivity: "I let my emotions cool before I act" (reverse coded). Goal orientation:"I have many long-term goals that I work to achieve." Vigilance: "I'm on my guard in most situations."

o Taylor & Seeman (1999). High vigilance, high emotional reactivity, & low goal orientation as measured by these scales are modestly associated with SES & "a variety of health symptoms" in the relatively small samples studied thus far. The scales are currently being used in large-scale studies to see if they continue to be associated with SES & major health outcomes in larger, more heterogeneous samples (e.g. Whitehall II, Taylor's HIV & Women Study, DR Williams' National Telephone Survey).

Medline search strategy: "Stress, Psychological" & ("Mortality" or "Cardiovascular diseases" or "Coronary Disease" or "Cerebrovascular Accident" or "Neoplasms" or "Immunologic Diseases or Autoimmune Diseases" or "Immune System"). 1987-2000.

Results include
o Levenstein S, Kaplan GA. (1998). Alameda County. How is "life stress" or "psychological stress" measured?

o Anda RF et al. (1992). National Health and Nutrition Examination Survey Epidemiologic Follow-up Study. Self-perceived stress & risk of peptic ulcer disease. How is "self-perceived stress" measured?

o Tennant C. (1999). Life stress, social support, & CHD. A review. How is "Life event stress" conceptualized?

o Persson LG et al. (1998). 12,982 Swedish men & women aged 30 or 35. Women, compared with men, had greater "mental stress" & "psychosocial strain."

o Cohen et al. (1998). "276 volunteers completed a life stressor interview & psychological questionnaires. they were then inoculated with common cold viruses & monitored for onset of disease. Although severe acute stressful life events (<1 month) were not associated with developing colds, several chronic stressors (1+ month) were associated with a substantial increase in risk of developing a cold. This relationship was attributable primarily to under- or unemployment and to enduring personal difficulties with family or friends."

o Wilhelmsen L et al. (1997). 2400 Swedish men & women aged 25-64 followed for 10 yrs. "Psychological stress" increased in women but not men.

o Aldwin CM et al. (1989). Normative Aging Study: "emotionality" predicts "stress"?

o Wright et al. (1996). Parental reports of "life stress" are associated with subsequent onset of wheezing in children between birth & one year.