Introduction to

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Introduction to Work and Health A
Social Epidemiological Approach to the Workplace
and Health Outcomes FacultyDr. Peter
Schnall June 18th 2009Universidad
Javeriana

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Why this program?

• With the exception of occupationally related
  injuries the medical profession tends to neglect
  the role of work in disease. For example, a
  traditional medical history asks only one
  question about work ones job title.
• The mainstream approach to stress and the
  workplace does not provide an adequate
  explanation for the epidemic of stress related
  diseases which we observe nor sufficient tools to
  prevent or alleviate stress(ors).
• While there are courses on occupational health,
  health psychology and on occupational psychology
  in different departments there is little
  integration of the material in these different
  fields.

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Course Objectives

• To understand the principles of a social
  epidemiological approach as this pertains to the
  workplace. To appreciate the historical context
  from which modern production modes arise,
  illustrated by an examination of the introduction
  of Taylorism and its successor lean production.
  
• To have a working familiarity with the leading
  work stress modelstheir theoretical basis, how
  they are operationalized in practice, and the
  strengths and weaknesses of the various
  assessment tools. To understand the concept of
  triangulation with regard to assessing
  workplace exposures.
• To be familiar with the empirical evidence
  linking psychosocial workplace factors to mental
  health outcomes, hypertension, coronary artery
  disease and other health outcomes

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Course Objectives cont

• To be able to describe some of the key
  physiological mechanisms by which work stressors
  affect the cardiovascular system and other target
  organs
• To be able to describe the key psychological
  mechanisms by which work stressors and other
  psychosocial factors impact upon mental health
  and risk behaviors
• To be able to take an occupational psychosocial
  history, to be able to use and interpret existing
  psychometric tools
• To understand the principles and practical
  aspects involved in job redesign. To be able to
  develop a plan of action for short- and
  longer-term improvement in a given workplace
• To be familiar with individual stress management
  approaches to stress at the workplace as well as
  health promotion

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Course Objectives Cont

• To be familiar with key legislative measures
  which reduce employee exposure to workplace
  stressors
• To develop an understanding of what constitutes
  healthy work

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Practicum

• The purpose of the course practicum is to
  familiarize students with work organizational
  characteristics that may act as work stressors
  and to give hands-on experience in evaluating
  occupational health exposures in working people
  using standardized and validated questionnaires
  and instruments.
• Each student will complete THREE exercises which
  will prepare them to complete a Work History
  Report and the Take-Home midterm and final.
• A participant-observation exercise
• Administer a psychosocial questionnaire packet to
  a working person.
• Complete the OSI questionnaire which will be
  combined with 2 in the Work History Report.

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1. Participant-Observation

• Students will complete a participant-observation
  exercise to observe a worker unobtrusively in
  their work environment (e.g. retail, grocery
  store, public transport etc.)
• The purpose of this exercise is to become
  familiar with work characteristics e.g. pace,
  demands, responsibility, creativity etc.
• Complete the worksheet during or after
  observation and turn in a ½ page report in
  Session 3 discuss your observations in class.

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2. Psychosocial Questionnaire Packet

• Each student will administer a psychosocial
  questionnaire packet take an occupational
  history on one person who must have a current
  paid job.
• The occupational work history will be of the most
  recent paid employment (can be summer/part-time
  employment).
• Students will obtain informed consent.
• The questionnaires and occupational history will
  have no identifying information (i.e., no names
  or social security numbers, etc).
• The interviewed person should be a full time
  employed worker.
• The information obtained should be about the
  current job.

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2. Psychosocial questionnaire packet cont.

• The packet will contain the following JCQ, ERI,
  GHQ and a short demographic questionnaire that
  determines education, age, race, gender and
  occupation.
• There will be an instruction sheet for each
  psychometric instrument provided
• The questionnaires will be scored by the students
  
• National norms will be provided for Job Strain to
  which the students may make qualitative and
  quantitative comparisons. They will be asked to
  map the quadrant location for their subject re
  job strain.
• They will determine whether or not ERI is
  present.
• Using the GHQ the students will determine the
  presence/absence of anxiety and depression, etc.
• The completed and scored packet will be due in
  Session 3.

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Work History Report (due Session 5)

• Utilize the psychosocial questionnaires and the
  OSI to write up an occupational work history
  about the working person you have administered
  the questionnaires to.
• Students will be challenged to interpret the
  psychosocial work exposure data in relation to
  the psychological outcomes taking into account
  the possibility that various issues such as
  denial or over-reporting may limit the inferences
  that can be made.
• This narrative should be succinct (1 to 2 pages
  maximum) and complete such that other health
  professionals and other team members could use it
  for diagnosis and treatment. Optimally, this
  history would indicate areas in which workplace
  modifications might be feasible (course
  instructors will provide an example).
• This body of information will form part of the
  basis for the take home midterm and final
  examinations for the course.

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Session 1 Intro lecture

• Working people develop a wide variety of
  illnesses during their working lives, manifested
  by symptoms, psychological distress, time lost
  from work, disability, physical incapacity and
  ultimately morbidity and mortality. How/whether
  these manifestations are connected to work is a
  critically important issue for those in the
  fields of medicine, occupational and public
  health.
• We will introduce the social epidemiologic
  approach, in which the workplace is viewed as a
  key leverage point for a wide variety of
  behavioral and health outcomes. The workplace
  can act relatively distally as well as
  proximately as a cause(s) of these outcomes. We
  view personality and individual factors as more
  proximal.

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Session 1 Intro lecture

• During the 19th Century physical/chemical/infectio
  us/nutritional exposures played a major role in
  health and illness. Urban areas/factories were
  associated with malnutrition, infectious diseases
  and shortened lifespan.
• In turn, these conditions stimulated
  resistance/reform and amelioration of the most
  egregious insults (wages, housing, working
  conditions). Child labor laws were passed and an
  ecological model of causation developed.

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Session 1 Intro lecture

• As living conditions in urban areas improved at
  the end of the 19th Century, such that major
  morbidity and mortality from infectious disease
  declined, workplace illnesses due to physical
  exposures such as Black lung disease gained
  increasing attention.
• Nearly 30 years after the federal government
  began addressing the cause of black lung, the
  disease still hasnt been eliminated. There is
  now recognition and protective legislation.
• Progress has been made. Coal workers
  pneumoconiosis, commonly referred to as black
  lung, and the coal mine dust that causes it, are
  less prevalent than before. Available data show
  that miners' exposure to respirable dust in coal
  mines has been reduced more than 70 percent over
  the last two decades. The prevalence of black
  lung disease among surveyed miners has declined
  by more than two thirds.

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Session 1 Intro lecture

• In the 20th Century another model emerged in
  contradistinction to an environmental or
  ecological model. The emphasis within modern
  medicine has been to focus upon biological
  disorders, sometimes resulting from individual
  traits, including genetic susceptibility,
  together with risk-behaviors (often referred to
  as the biomedical model).

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Session 1 Intro lecture

• At the same time the nature of environmental
  exposures has been changing. While the proportion
  of workers exposed to toxic physical and chemical
  agents is on the decline in the modern workplace
  of post-industrial countries, the importance of
  another set of noxious exposures of a
  psychosocial nature has become increasingly
  recognized.

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Session 1 Intro lecture

• In the case of physical occupational hazards the
  cause of injury/disease could be linked more
  directly to environmental exposures.
• In contrast, for psychosocial risks the
  connections are more difficult to assess and
  document. The etiologic model becomes more
  complicated.

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Two Views

• Social Epidemiology Model - negative health
  outcomes (illnesses) are due to the impact of
  social epidemiologic factors (in general class,
  work, race and gender), and in this case a focus
  on workplace stressors, acting on the individual
  gt eliciting cognitive processes that result in
  physiological disturbance (e.g., depression and
  hypertension).

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Predominant View

• Biomedical Model - or is it the other way around
  with disease the result of disruption of
  psychological processes wherein subjective
  perceptions, behaviors and personality factors
  (e.g., neuroticism) are of primary importance
  (i.e., disease proceeds from the individual to
  the environment). This latter views work
  environment as tolerable to vast majority of
  humans but in some cases there is a lack of fit
  between the individual and their environment.
  Workplace stressors are frequently absent in this
  formulation.

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The Role of Work (Job Characteristics) in Health
and Disease

• We will review throughout this course the
  developing evidence of the importance of
  workplace risk factors.
• In this perspective, a key intellectual task
  becomes defining and measuring those psychosocial
  conditions of burden that surpass normal human
  capacity.
• We use social epidemiological methods to identify
  those psychosocial stressors which impact on
  large populations of people (e.g. job strain,
  effort-reward imbalance, etc.).

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The New York City Work Site Blood Pressure (BP)
Study

• Based at Weill Medical College of Cornell
  University- New York Hospital
• Began in 1985 as a case-control study
• 283 men initially enrolled at 8 large NYC work
  sites
• Funding became available (after studying 7 sites)
  to
• conduct a prospective study (evaluate Ss every
  3-4 yrs)
• enroll women
• Currently, 472 subjects enrolled at 10 sites (38
  women)
• maximum of 4 evaluations 10 years of follow-up

Work Site BP Study
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The New York City Work Site BP Study Eligibility
criteria

• aged 30-60 at recruitment
• full-time employee (30 hours/wk)
• no second job requiring more than 15 hours/wk
• no evidence of CHD
• screening BPs less than 160/105 mm Hg
• able to read and speak English
• body mass index lt 32.5 kg/m² at screening
• at current worksite gt3 yrs before recruitment and
  before Dx of high BP (only 1 yr at 8th site)

Work Site BP Study
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Job Strain and Work Ambulatory BP (men, Time 1
and Time 2)
Time 1 Time 2
Time 1 Time 2 (n195) (n195)
(n195) (n195)




Systolic AmBP
Diastolic AmBP
controlling for age, education, body mass index,
race, smoking, alcohol use, work site
Work Site BP Study
plt.001
Schnall PL, Schwartz JE, Landsbergis PA, Warren
K, Pickering TG. Psychosomatic Medicine
199860697-706.
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Job Strain Change Variable
Time 1
Time 2
(baseline)
(3 years later)
Yes (n15) (chronic strain)
Yes
Job Strain
No (n25)
Yes (n17)
No
No (n137) (referent)
Work Site BP Study
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Job Strain change and Work Systolic Ambulatory BP
(n195 men, Time 1 and 2)
Strain-T1 no no yes yes
no no yes yes Strain-T2 no
yes no yes no yes no
yes
Time 2 (p.0015)
Time 1 (p.0017)
controlling for age, education, body mass index,
race, smoking, alcohol use, work site
Work Site BP Study
Schnall PL, Schwartz JE, Landsbergis PA, Warren
K, Pickering TG. Psychosomatic Medicine
199860697-706.
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Job Strain change and 3-yr Work Ambulatory BP
change (n195 men, Time 1-2)
Strain-T1 no no yes yes
no no yes yes Strain-T2
no yes no yes no yes
no yes
Ref


Systolic AmBP
Diastolic AmBP
controlling for age, race, body mass index,
smoking, alcohol use, work site
Work Site BP Study
plt.05, plt.01, (vs Ref group)
Schnall PL, Schwartz JE, Landsbergis PA, Warren
K, Pickering TG. Psychosomatic Medicine
199860697-706.
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Job Strain and Work Ambulatory Systolic BP by
Occupational Status (n283 men, Time 1)
Job Strain No Job Strain
White-collar Clerical Blue-collar
White-collar Clerical Blue-collar



Ref
INTERACTION TERM p.13
controlling for age, body mass index, race,
smoking, alcohol use and work site
plt.10, plt.05 (vs Ref group)
Landsbergis et al. In Adler, NE, Marmot M, McEwen
BS, Stewart J (eds.) Socioeconomic status and
health in industrialized nations (pp. 414-6). New
York New York Academy of Sciences, 1999.
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The Importance of Psychosocial Factors in
Hypertension Findings from the Cornell U.M.C.
Work Site Ambulatory Blood Pressure Project

• Case-Control Study Job Strain and Hypertension
  Odds Ratio 2.7
• Cross-Sectional Study Job Strain and Ambulatory
  SBP 6.6 mm Hg
• Job Strain and Ambulatory DBP 4.0 mm Hg
• Longitudinal Study Repeated exposure Job Strain
  and AmSBP 12 mm Hg
• Repeated exposure Job Strain and AmDBP 9 mm Hg
• Population Attributable Risk 27 1
• 1calculation based on OR of 2.7 and prevalence
  rate of Job strain of 20

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The Role of Work (Job Characteristics) in Health
and Disease (continued)

• The social epidemiologic model moves from left to
  right ? 1) psychosocial stressors ? 2) cognitive
  processing can be influenced by a) personality
  factors, b) coping mechanisms, c) other
  neurological factors ? 3) physiological arousal
  as well psychological disturbances.
• There is now evidence of the mechanisms by which
  the brain mediates these stressors this is the
  field of cognitive ergonomics.
• Tony Gaillard 1993 article has elegantly linked
  psychosocial factors and job strain into the
  realm of brain mechanisms of attention and mental
  load and how this plays out in terms of stress.
  (Session 4)

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The Role of Work (Job Characteristics) in Health
and Disease (continued)

• This approach leads to a description/identificatio
  n of health outcomes that are most likely
  especially associated with modern production -
  repetitive motion injuries, hypertension, cvd and
  a number of psychological conditions. Here is
  where we again find Charlie. He could be a
  statistic, one of millions, but in Modern Times
  he is the Canary in the Coal Mine who gives a
  human face to the consequences of modern working
  life.
• In understanding psychosocial stressors in terms
  of their social origins we argue that the work
  organizations under modern conditions of
  production are driven for economic reasons to
  maximize human productivity and often this will
  be at the expense of the human nervous system.
• At all times this process is limited by the
  constraints of biological vulnerability and
  social and political resistance.

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Two Differing Views - Two Different Sets of
Interventions

• Social Epidemiologic Model - focuses on the
  organization of work.
• Biomedical model focus is on the individual via
  stress management models and drug therapy.
• These are not necessarily contradictory
  positions. Both these types of interventions may
  be useful and complementary (prevention and
  treatment)

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The Importance of OHP

• The new field of OHP is incorporating this kind
  of social epidemiologic approach.
• OHP practitioners are potentially key players in
  identifying workplace risk factors which can
  impact negatively on individuals.
• They can play key leadership role in health
  promotion/protection at the worksite by liasoning
  among other related concerned individuals.
• OHP practitioners can help develop new strategies
  to create a healthy workplace.
• Or perhaps we should train industrial hygienists,
  OHNs, and others for this role.

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• End Hour 1