ASSESSMENT OF PSYCHOLOGICAL STRESS Pittsburgh Mind-Body Center Summer Institute June 4, 2008 Tom Kamarck, Ph.D. Barbara Anderson, Ph.D.

SOCIAL ENVIRONMENT PSYCHOLOGICAL STRESS DEFINITION MEASUREMENT VULNERABILITY TO DISEASE Low Socioeconomic Status Natural Disasters Bereavement Unemployment Marital Strain Job stress Caregiving Discrimination

GOALS 1.Major approaches to conceptualization and measurement of stress– pro’s and cons. 2. Initiatives by PMBC faculty to improve our ability to quantify chronic stress exposure.

ORGANISM ENVIRONMENT

ORGANISM ENVIRONMENT

ORGANISM ENVIRONMENT

DEFINITIONS OF STRESS Response-based model (Selye, 1974) “Stress is the nonspecific response of the body to any demand made upon it.” Stimulus-based model (Holmes & Rahe, 1967) Stress involves “…events whose advent…requires a significant change in the ongoing life pattern of the individual.” Transactional model (Holroyd & Lazarus, 1982) Stress involves the “judgment that environmental or internal demands tax or exceed the individual’s resources for managing them.”

THE TEMPORAL DIMENSION ORGANISM ENVIRONMENT ORGANISM ENVIRONMENT ORGANISM ENVIRONMENT

THE TEMPORAL DIMENSION ACUTE STRESS RESPONSES CHRONIC STRESS RESPONSES SHORT TERM STRESSOR EXPOSURE LONG TERM STRESSOR EXPOSURE SHORT TERM STRESSFUL TRANSACTIONS LONG TERM STRESSFUL TRANSACTIONS RESPONSE- BASED STIMULUS- BASED TRANSACTION ACUTE CHRONIC

DEFINITIONS OF STRESS Response-based model (Selye, 1974) “Stress is the nonspecific response of the body to any demand made upon it.” Stimulus-based model (Holmes & Rahe, 1967) Stress involves “…events whose advent…requires a significant change in the ongoing life pattern of the individual.” Transactional model (Holroyd & Lazarus, 1982) Stress involves the “judgment that environmental or internal demands tax or exceed the individual’s resources for managing them.”

DEFINITIONS OF STRESS Response-based model (Selye, 1974) “Stress is the nonspecific response of the body to any demand made upon it.” NEUROBIOLOGICAL RESPONSES: STRENGTHS: Objective assessments WEAKNESSES: Many-to-one relationship between response determinants and neurobiological responses.

DEFINITIONS OF STRESS Response-based model (Selye, 1974) “Stress is the nonspecific response of the body to any demand made upon it.” SELF-REPORT RESPONSES: STRENGTHS: Salient, face valid. WEAKNESSES: Psychological symptoms are frequently characterized as outcome measures in the relationship between stress and adaptation rather than as predictors.

DEFINITIONS OF STRESS Response-based model (Selye, 1974) “Stress is the nonspecific response of the body to any demand made upon it.” Stimulus-based model (Holmes & Rahe, 1967) Stress involves “…events whose advent…requires a significant change in the ongoing life pattern of the individual.” Transactional model (Holroyd & Lazarus, 1982) Stress involves the “judgment that environmental or internal demands tax or exceed the individual’s resources for managing them.”

Stimulus-based model What is “stressful” about the demands of the environment? Relevant psychological processes. What are the major temporal domains that are important to assess? (daily hassles, life events, chronic difficulties) How do the demands of the environment summate? What are the relevant life domains that should be the focus of our attention (occupation, marriage, caregiving responsibilities)?

Stimulus-based model Life events approach –Adolf Meyer’s “life chart” ( ) –Harold Wolff NY Hospital-Cornell –Thomas Holmes 1955 Schedule of Recent Experiences –Richard Rahe Social Readjustment Rating Scale

Stimulus-based model Life events approach Assumptions of the original method: What makes stress stressful? Adaptation. Impact of events is linear, additive and cumulative. Equal effects across individuals.

Schedule of Recent Experience (1967) EXAMPLE ITEMS 1.Mark under the appropriate time periods when there has been either a lot more or a lot less trouble with the boss. 8.Mark under the appropriate time periods when there was a major change in number of family-get-togethers (e.g., a lot more or a lot less than usual). 26.Mark the number of times in each appropriate time period that you had an outstanding personal achievement. 29.Mark the number of times in each appropriate time period that there was a major change in working hours or conditions. 32. Mark the number of times in each appropriate time period that there was a major change in living conditions (building a new home, remodeling, deterioration of home or neighborhood).

Stimulus-based model Life events approach STRENGTHS: In theory, these measures allow us to identify the environmental sources of stress in a manner that is unconfounded by the individual’s reaction or coping style. WEAKNESSES: 1. Problems with subjectivity (threshold for item endorsement) 2. Problems with reliability (retest not bad, but only 60 % of items endorsed at one time are also endorsed at another). 3. Problems with memory accessibility (fall off about 5 % per month). 4. Problems with content validity. 5. Uneven representation of chronic difficulties.

Stimulus-based model Life events approach STRENGTHS: In theory, these measures allow us to identify the environmental sources of stress in a manner that is unconfounded by the individual’s reaction or coping style. WEAKNESSES: 1. Problems with subjectivity (threshold for item endorsement) 2. Problems with reliability (retest not bad, but only 60 % of items endorsed at one time are also endorsed at another). 3. Problems with memory accessibility (fall off about 5 % per month). 4. Problems with content validity. ONE PROPOSED SOLUTION: INVESTIGATOR-BASED METHODS

A key distinction between Investigator-Based (IB) and Self-Report (SR) Methods In IB methods, the responsibility for identifying and rating severity of “stressors” lies with the investigator not with the respondent. Final interpretation and ratings are made by trained staff /investigator in conjunction with the subject’s self-report. Severity ratings are based upon contextual circumstances surrounding each stressor (for example, pregnancy with or without stable family circumstances) and with the assistance of dictionary or coding manual, rather than upon respondent’s subjective reaction to the event in the course of its description.

Example of a checklist item: “Serious illness of a close family member” How serious is “serious” How close is “close” What constitutes an “illness” Who constitutes a “family member”

What is LEDS? * Life Events and Difficulties Schedule (LEDS; Brown & Harris, 1979; 1989) Semi-structured interview that allows one to identify current life stressors that threaten one’s goals and commitments, using behavioral indicators of threat (verbal or written job performance ratings) goal investment (primary vs. secondary wage earner). Severity ratings are based on the life circumstances of the individual. * LEDS is considered to be the “gold standard” of investigator-based assessment of life stress.

Stimulus-based model LEDS –Calendar method –Multiple domains – “Dictionary” coding system Assumptions : What makes stress stressful? Contextual threat= threat to important values and commitments. Impact of events involves threshold model. Interrelated events are not double counted. Effects of stress assumed to vary according to individuals’ biographical characteristics.

How do you implement LEDS? Three part process: 1. Interview 2. Rating procedure 3. Consensus process

Why Use These Methods? Advantages 1.Checklists have demonstrated poor test-retest reliability. 2.IB methods allow greater precision in the consistent identification of stressors as well as their onset and offset. McQuaid et al. (1992) 62% of checklist- identified stressors were found to be discrepant with those identified by the LEDS.

Why Not Use These Methods? Disadvantages 1.Cost of implementation –Training is necessary –Respondent/investigator burden in terms of time and effort for administration is considerable –Rating and independent review of ratings can be lengthy 2.Research considerations –Not widely used in the literature because of cost and training –Extant evidence supporting their use in terms of predictive validity is limited

DEFINITIONS OF STRESS Response-based model (Selye, 1974) “Stress is the nonspecific response of the body to any demand made upon it.” Stimulus-based model (Holmes & Rahe, 1967) Stress involves “…events whose advent…requires a significant change in the ongoing life pattern of the individual.” Transactional model (Holroyd & Lazarus, 1982) Stress involves the “judgment that environmental or internal demands tax or exceed the individual’s resources for managing them.”

DEFINITIONS OF STRESS Transactional model (Holroyd & Lazarus, 1982) Stress involves the “judgment that environmental or internal demands tax or exceed the individual’s resources for managing them.” ASSUMPTIONS: –Stress involves balance between demands and resources. –The mechanism by which these are compared involves a judgment or a cognitive appraisal process.

DEFINITIONS OF STRESS Transactional Model Primary Appraisal“What is at stake?” Secondary Appraisal“Can I cope?”

DEFINITIONS OF STRESS Transactional Model Appraisal as “final common pathway by which diverse personal and environmental variables influence the outcomes of stressful encounters.” Transactional model personenvironment

Perceived Stress Scale Cohen, Kamarck & Mermelstein (1983). J Health and Soc Bhr, 24, In the last month, how often have you felt that you were unable to control the important things in your life? 6. In the last month, how often have you felt confident about your ability to handle your personal problems? 7. In the last month, how often have you felt that things were going your way? 14. In the last month, how often have you felt difficulties were piling up so high that you could not overcome them?

DEFINITIONS OF STRESS Transactional Model STRENGTHS Takes into consideration individual differences in perception or appraisal. WEAKNESSES Confounded with a number of dimensions, such as depressive symptoms and neuroticism, which may be important to disaggregate from the construct of stress.

Cognitive Appraisal and the Brain Joseph LeDoux Cognitive appraisal may not be necessary in order for a stimulus to elicit an emotional response that alters the physiology of the organism.

THE TEMPORAL DIMENSION ACUTE STRESS RESPONSES CHRONIC STRESS RESPONSES SHORT TERM STRESSOR EXPOSURE LONG TERM STRESSOR EXPOSURE SHORT TERM STRESSFUL TRANSACTIONS LONG TERM STRESSFUL TRANSACTIONS RESPONSE- BASED STIMULUS- BASED TRANSACTION ACUTE CHRONIC

THE CHALLENGE OF EXPOSURE ASSESSMENT As with other environmental risk factors (e.g., passive smoking, radiation) the impact of psychosocial stress on health should be expected to vary as a function of the frequency, duration, or intensity of daily exposure. Documenting the extent of environmental risk exposure (not just intensity but also frequency and duration) is a challenge for epidemiologists who study the risk factors related to disease, and all the more so when such risk factors involve psychosocial processes. When it comes to the measurement of psychosocial stress, we have not yet adequately addressed this challenge.

EXPOSURE BIOLOGY PROGRAM Enhance our ability to assess environmental exposures (e.g., environmental and chemical toxins) that may interact with genetic propensities to influence health environmental toxins, drugs & chemical agents, nutritional factors, physical activity, psychosocial stress. Common Denominator: Frequency and duration of exposure to these factors may be difficult to assess using standard methods.

INVESTIGATOR-BASED INTERVIEW APPROACH Accuracy in assessment of stressor onset, offset using objective criteria duration of stressor exposure. ECOLOGICAL MOMENTARY ASSESSMENT THE CHALLENGE OF EXPOSURE ASSESSMENT Ability to collect representative time samples frequency and duration of exposure.

THE TEMPORAL DIMENSION CHRONIC STRESS RESPONSES LONG TERM STRESSOR EXPOSURE LONG TERM STRESSFUL TRANSACTIONS RESPONSE- BASED STIMULUS- BASED TRANSACTION CHRONIC INVESTIGATOR-BASED INTERVIEW APPROACH EMAEMA ECOLOGICAL MOMENTARY ASSESSMENT

INVESTIGATOR-BASED INTERVIEW APPROACH Accuracy in assessment of stressor onset, offset using objective criteria duration of stressor exposure. THE CHALLENGE OF EXPOSURE ASSESSMENT Life Events and Difficulties Schedule (LEDS) (Brown & Harris, 1989). --chronic “difficulties” as well as acute events --extensive training, administration & scoring time

LIFE EVENTS ASSESSMENT PROFILE (LEAP) --maintained contextual assessment features of LEDS. --maintained calendar methods for determining onset, offset of chronic stressors that takes into consideration fluctuation in magnitude of effects over time. -- Extracted key contextual features of stressors imbedded in coding system of LEDS: structured behavior-specific probes. Barbara Anderson (Pitt) and Elaine Wethington (Cornell University)

Computer Assisted Personal Interview (CAPI) system with relational database features LIFE EVENTS ASSESSMENT PROFILE (LEAP)

10 different life domains in LEAP, skip patterns can be quite complex. Relational database features will allow us to interact with calendar system, updated throughout the interview, allowing us to characterize the onset, offset of events and difficulties across domains. Use of computerized algorithms for navigating through interview is expected to result in considerable time savings in interview administration. Automated and instantaneous scoring of protocol will eliminate need for scoring, consensus meetings, further reducing time requirements. LIFE EVENTS ASSESSMENT PROFILE (LEAP)

CAPI will permit us to administer the LEAP by phone. One of first attempts to develop automated administration system for comprehensive interview assessment of life stressors. LIFE EVENTS ASSESSMENT PROFILE (LEAP)

ECOLOGICAL MOMENTARY ASSESSMENT THE CHALLENGE OF EXPOSURE ASSESSMENT Ability to collect representative time samples frequency and duration of exposure. Assumption: Chronic stress leaves its signature on the behavioral and biological events of our daily lives. Limitations of autobiographical memory for reconstructing frequency, duration of daily events (Bradburn et al., 1987).

ECOLOGICAL MOMENTARY ASSESSMENT (EMA) APPROACH TO THE ASSESSMENT OF PSYCHOSOCIAL STRESS RATIONALE 1.EMA measures may allow us to more accurately capture the frequency and duration of psychosocial stress “exposure” as it pertains to our daily experience. 2.EMA measures allow us to examine mechanistic hypotheses linking stress with disease– can be linked with moment-to- moment changes in biological processes, e.g., endocrine or hemodynamic activity. 3.EMA measures allow us to examine the importance of setting effects relevant to the occurrence and consequences of stress (e.g., social interactions with partner vs. others; health effects of job demands vs. household demands vs. neighborhood demands).

Five psychological processes linked with stress, acute cardiovascular activation, and disease risk NEGATIVE AFFECT AROUSAL TASK DEMAND TASK CONTROL SOCIAL CONFLICT Kamarck et al. (1998). Health Psychology, 17,

KARASEK JOB CONTENT QUESTIONNAIRE Psychological Demands 1.My job requires working very fast. 2. My job requires working very hard. 3. I am not asked to do an excessive amount of work. (R) 4. I have enough time to get the job done. (R) 5. I am free from conflicting demands that others make. (R) Decision Latitude e.g., 1.My job allows me to make a lot of decisions on my own. 2. On my job, I have very little freedom to decide how I do my work.(R) 3. I have a lot of say about what happens on my job. (R)

TASK DEMAND Activity last 10 minutes Required working hard? NO==================YES NO==================YES Required working fast? NO==================YES Juggled several tasks at once? NO==================YES NO==================YES DECISIONAL CONTROL Activity last 10 minutes Could change activity if you chose to? NO==================YES NO==================YES Choice in scheduling this activity? NO==================YES NO==================YES Adapted from Karasek Job Content Questionnaire

TABLE 1. DIARY RATINGS AT HOME AND WORK (n = 176) Home Worktp Task Demand Dec Control Negative Affect Arousal Social Conflict

Five psychological processes associated with moment-to-moment changes in blood pressure SBP p NEGATIVE AFFECT AROUSAL TASK DEMAND TASK CONTROL SOCIAL CONFLICT Kamarck et al. (2002). Physiology and Behavior, 77,

TABLE 2. FOUR MONTH TEST-RETEST RELIABILITY OF DIARY SUBSCALES (N = 354) rp Task Demand Dec Control Negative Affect Arousal Social Conflict

Global Job RatingsDemandControl Mean Momentary Ratings at Work Demandr =.53 ***---- Control *** *** <.0001 GLOBAL VS. MOMENTARY RATINGS OF DEMAND AND CONTROL (N=152)

Aggregated over 6-day period, mean ratings of Task Demand and Task Control associated with chronic elevations of blood pressure during daily life Mean Task Demand / Mean Task Control Kamarck et al. (2002). Physiology and Behavior, 77,

Mean ratings of Task Demand and Task Control related in the expected direction with measures of carotid artery atherosclerosis Kamarck et al. (2004). Health Psychology, 23, b=.02, F (1, 328) = 8.44, r2 =.02, p =.004

Global questionnaire measures of Psychological Demands and Decision Latitude (JCQ) were not significantly correlated with mean IMT. e.g., Demands (b=.00, p=.59, r 2 =.00). Kamarck et al. (2004) Health Psychology, 23, Mean ratings of Task Demand and Task Control related in the expected direction with measures of carotid artery atherosclerosis

Mean ratings of Task Demand and Task Control related in the expected direction with measures of carotid artery atherosclerosis Task Demand ratings were associated with atherosclerosis even among those who were not employed during the study (n=141). (b=.02, p=.03, r2=.03). Among employed Ss (n=152), association did not differ as a function of whether ratings were derived from inside or outside of the workplace. Work: (b=.02, p=.02, r 2 =.03). Nonwork: (b=.02, p=.05, r 2 =.02).

Mean ratings of Task Demand and Task Control related in the expected direction with measures of carotid artery atherosclerosis Kamarck et al. (2007). Health Psychology, 26,

ECOLOGICAL MOMENTARY ASSESSMENT (EMA) APPROACH TO THE ASSESSMENT OF STRESS Conclusion: There may be some important utility to this new assessment approach as a means of understanding how the cumulative effects of chronic psychosocial stress impact on health outcomes over the course of daily living.

ECOLOGICAL MOMENTARY ASSESSMENT THE CHALLENGE OF “EXPOSURE ASSESSMENT” Ability to collect representative time samples frequency and duration of exposure. Our contribution at this point: Development of more user-friendly assessment technologies. Refine our elaborate upon our measures, in order to be able to best characterize the types of daily stressors that are strongest triggers for biological systems thought to enhance our susceptibility to disease.

e-Watch (Siewiorek, Smailagic) Human Computer Interaction Institute (HCII, CMU)

E-WATCH In contrast to standard PDA, more flexible in terms of number of input, output, and prompting modalities available. Interview presentation: visual (watch face) auditory (earbug) Responses: manual (button push on watch) speech (earbug phone) gestural (accelerometer in watch)

E-WATCH We are in process of examining relative advantages of e-watch over PDA (user satisfaction and compliance) relative merits of each of these input and output modalities under various situations and for those (low literacy, manual laborers) assumed to have difficulty with “traditional” PDA assessments.

OUR GOALS IN THE YEARS AHEAD Phase 1 (Year 1) Development of testing devices for each of these two methods. Phase 2 (Year 2-3) Item analysis and validation of instrument content. Phase 3 (Year 3-4) Cross validation and reliability testing. Phase 4 (Year 4) Documentation, standardized training procedures, manufacturing plans. EXPOSURE BIOLOGY PROGRAM

EXPOSURE BIOLOGY PROGRAM University of Pittsburgh Computer-assisted technologies for tracking exposure to psychosocial stress. Johns Hopkins & NIDA Real-time assessment of individual and neighborhood exposure to drugs and stress using hand-held electronic diaries and position technology (Kirk, Preston) University of Memphis Wireless skin patch sensors to dtect and transmit addiction and psychosocial stress data (Kumar) Rensselear Polyutechnic Institute A personal light-monitoring device for reducing psychosocial stress (Rea) UCLA Handheld salivary biosensor of psychosocial stress (Shetty) MIT Enabling population-scale physical activity and experience sampling measurement on common mobile phones (Intille)

We’re just getting off the ground…