Public Lecture at FIOCRUZ
Rio de Janeiro
29 November 2011
Work stress and health in the era of
economic globalisation
Johannes Siegrist, PhD
Professor and Director
Department of Medical Sociology
University of Duesseldorf, Germany
Importance of work for health
Work …
 provides a source of regular income and related
opportunities
 provides a source of personal growth and training
opportunities
 provides social identity, social status and related rewards
 enables access to social networks beyond primary groups
 influences a person’s self efficacy and self esteem
 exposes a person to differential quality of work
environment
Quality of work and health
Traditional focus: workplace
 Chemical & physical hazards and specific ergonomic
conditions reduce employees’ health and increase
injury risk
 Domain of occupational medicine and safety
Modern focus: work organization and employment
conditions
 Specific features enhance or reduce employees’ health
through psychosocial stress-related mechanisms
 Domain of ‚new‘ occupational health research and
policy
Significant changes in the nature of
work and labour market
 fewer jobs defined by physical demands,
more by mental and emotional demands
 increase of service sector, computer-based job
profiles
 increase in flexible work arrangements,
part-time work, de-standardized work arrangements
 growing job instability / discontinuity;
precarious work and unemployment
 Segmentation of labour market; social gradient of
quality of work and employment
Economic globalisation
Expansion of free market principles and technological
innovations from high income to middle and low income
countries

International organizations (WB, IMF, WTO)

Transnational corporations

Transnational capital flow

Globalized labor market

Neo-liberal policies (deregulation, disinvestment
in welfare states, reduced impact of trade unions)
Globalised production
Effects of economic globalisation: Labour
market consequences in developed countries
Increased pressure of rationalisation
(mainly due to wage competition)
Downsizing, Merging, Outsourcing
Work
intensification
Job
insecurity
Low wage /
salary
Work and health: What is known?
Long-term
unemployment
Physical/chemical
hazards
Precarious work, job
instability
Overtime/shift work
Stressful work in more
privileged jobs
Long-term unemployment and mortality (10
yrs. follow up 1990-2000)
6
5,35
men (n=15653/3858)
5
Hazard Ratio
4
women (n=35770/3395)
2,81
4,23
2,91
2,66
2,36
3
2
1
0
total
cardiovascular
Source: M. Kivimäki et al. (2003), Am J Epidemiol, 158:663-668.
external
Key messages
1. Work stress is a risk factor of several major
chronic disorders and contributes to social
inequalities in health.
2. Scientific evidence is particularly strong in high
income countries.
3. With economic globalisation this evidence
extends to rapidly developing countries.
4. Evidence-based policy interventions at the
organizational, national and international level
are needed to reduce stressful work and
employment and related health inequalities.
Work stress and health: evidence from
high income countries
Definition of work stress
A working person‘s reaction to a threatening
demand (stressor) that taxes or exceeds
her/his capacity of successful response.
 Negative emotions, e.g. anxiety, frustration,
helplessness
 Physiological stress responses (hormones,
ANS)
Risk of stress-related disorders: Function of
duration and intensity of stressor
Main diseases related to work stress
Mental illness
Cardiovascular
diseases
Musculoskeletal
disorders
Reproductive
hazards
Threat to control and social reward by experimental
manipulation of social status in male macaques:
effects on coronary atherosclerosis
0,9
0,8
0,8
0,7
0,7
0,6
0,6
0,5
0,5
0,4
0,4
0,3
0,3
0,2
0,2
0,1
0,1
0
0
Mean growth of
atherosclerotic plaques
(mm2)
0,9
stable
unstable
Social group
dominant
subordinate
Source: J.R. Kaplan et al. (1994), Am Heart J, 128: 1316.
with
without
Beta-blocking agent
(only unstable group)
Work stress: How to identify toxic
components within complex environments?
negative
emotions
stress-related
disorders
stress responses
Why do we need theoretical models?
A theoretical model...
 reduces the complex reality at work to critical (‚toxic‘)
components
 allows for generalisation beyond single observations
 provides an explanation of associations between work
and health
 serves as a guide for health-promoting interventions at
work
Three theoretical models of the psychosocial
work environment
 Demand-control model
(R. Karasek, 1979;
R. Karasek & T. Theorell, 1990)
 Features of
job tasks
 Effort-reward imbalance model
(J. Siegrist, 1996;
J. Siegrist et al., 2004)
 Features of
work contracts
 Organizational justice model
(J. Greenberg, 1990;
M. Elovainio et al., 2002)
 Features of
organizational
procedures
The demand-control model
(R. Karasek 1979; R. Karasek & T. Theorell 1990)
high
low
low
Scope of decision/control
Quantitative demands
high
low
distress
active
high
distress
passive
The model of effort-reward imbalance
(J. Siegrist 1996)
Extrinsic components
- labour income
- career mobility / job security
- esteem, respect
demands / obligations
reward
effort
motivation
(‘overcommitment‘)
motivation
(‘overcommitment‘)
Intrinsic component
Why do people continue to work in ‚high
cost – low gain‘ conditions?
 Dependency
The working person has no alternative choice in the labour
market: accepting contractual unfairness is preferred to job
loss.
 Strategic choice
The working person accepts imbalance in order to improve
future career development (anticipatory investment).
 Overcommitment
The working person exhibits a motivational pattern
of excessive work-related commitment where investments
often exceed gains. Overcommitment is either due to
personality or due to pressure at work.
Conceptual Differences between the DemandControl (DC) and the Effort-Reward Imbalance Model
(ERI)
DC
ERI
 Focus on job task: high
demands and low
control
 Focus on work contract:
non-reciprocity of efforts
and rewards
 Threat to personal
control / low self
efficacy
(cognitive appraisal)
 Threat to social rewards
/ low self esteem
(affective information
processing)
 Democracy,
participation
 Distributive justice,
contractual fairness
The Organizational Justice Model
 Procedural justice
Perceptions of consistent, accurate, unbiased and
ethical rules of procedures
 Relational justice
Perceptions of polite, fair interactions from supervisors
 Distributive justice
Perceptions of appropriate distribution of job tasks
and gains among employees
So far, procedural and relational justice only were
measured with relevance to health and performance.
Measurement of the models
 Both models are measured by a standardized selfassessed questionnaire which can be applied to a variety of
different occupational groups:
- Job Content Questionnaire (JCQ) (R. A. Karasek)
www.workhealth.org
- Effort-Reward Imbalance Questionnaire (ERI)
(J. Siegrist)
www.uni-duesseldorf.de/MedicalSociology
 Both questionnaires fulfill criteria of psychometric quality
(factorial structure of scales, reliability, discriminant and
predictive validity etc.).
 Both questionnaires are available in a number of languages
and have been used in comparative international studies.
Measurement of effort-reward
imbalance at work
 Scale ‚effort‘ (6 Likert-scaled items) = perceived
demands (Cronbach‘s α = .72)
 Scale ‚reward‘ (11 Likert-scaled items) = experienced or
promised gratifications (Cronbach‘s α = .83)
- 3 subscales:(a) salary and promotion, (b) esteem,
(c) job security
- ‚ratio effort/reward‘ =
sum score ‚effort‘ / (sum score ‚reward‘  6/11)
 Scale ‚overcommitment‘ (6 Likert-scaled items) =
pattern of coping with demands and rewards
(Cronbach‘s α = .76)
For detailed information see:
http://www.uni-duesseldorf.de/MedicalSociology/
Psychometrically validated scales of the ERI
questionnaire
• Languages:
– German, English, Swedish, Dutch, French,
Italian, Spanish, Portuguese, Jaapanese,
Chinese/Taiwanese, Korean, Thai
– The Brazilian version:
• D. Chor et al. (2008) Cad Saude Publica 24:
219-224
• R. Härter Griep et al. (2009) Int Arch Occup
Environ Health 82: 1163-1172
Public health relevance of stress-related
disorders
Focus on coronary heart disease and depression
„By the year 2020 depression
and coronary heart disease will be the
leading causes of premature death
and of life years defined by disability
(DALY‘s) worldwide.“
(Murray and Lopez 1996)
What is the scientific evidence of a direct
association of work stress with disease?
Methodological approaches:
epidemiological and experimental
Epidemiological research:
 prospective observational cohort study (gold standard)
 cross-sectional and case-control-study (weaker
evidence)
 intervention study (limited options)
Experimental research:
 laboratory experiments (limited ecological validity)
 ambulatory monitoring at work (limited control)
Mortality (rate ratio; 25 years) according to
occupational position: the Whitehall-Study N=18.000)
Mortality (rate ratio)
2,2
administrative
professionals
clerical
other
2
1,8
1,6
1,4
1,2
1
0,8
0,6
0,4
40-64 years
64-69 years
Source: M. Marmot & M.J. Shipley (1996), Brit Med J, 313: 1177.
70-89 years
Social inequality of work stress in the
Whitehall II-Study
Effort-reward
imbalance model:
% imbalance between
effort and reward
80
60
40
20
0
Demand-control
model:
% job strain
(observer judgement)
high,
middle,
low occupational status
30
20
10
0
men
women
Work stress (effort reward imbalance/job control) and
CHD incidence, men and women: Whitehall II-Study
3
3
*
2,5
2
2
1,5
1,5
1
1
0,5
0,5
No work
stress
*
2,5
High effort or High effort
low reward
and low
reward
No work
stress
Intermediate
job control
Low job
control
adjusted for age, sex, length of follow-up
+ alternative work stress model
+ grade, coronary risk factors, negative affect
Source: H. Bosma et al. (1998), Amer J Publ Health, 88: 68-74
* p < .05
Overtime work increases the risk of coronary heart
disease: Whitehall II study
1,8
1,6
Mean daily overtime
in hours (h) at
baseline
1,4
1,2
1
0,8
0,6
No overtime
1h
2h
3-4h
0,4
0,2
0
(N=6014 civil servants) followed over 11 years*;
* Hazard ratios adjusted for 21 risk factors
Source: Virtanen M et al. (2010) Eur Heart J: doi10.1093/eurheartj/ehq124
4-year increase
In plaque height (mm)
Workplace demands, economic reward,
and 4-year progression of carotid atherosclerosis
(plaque height) in 940 Finnish men
0,35
0,33
0,3
0,25
0,27
high
0,27
0,26
low
0,2
low
high
Economic rewards
Source: J. Lynch et al. (1997), Circulation, 96: 302
p = .04 (adj.)
Mean systolic blood pressure (mmHg) in men
over a working day according to overcommitment
and occupational grade (N=105)
140
overcommitment +,
occup. grade low
mmHg
135
130
overcommitment +,
occup. grade high
125
overcommitment -,
occup. grade high
120
overcommitment -,
occup. grade low
morning
noon
afternoon
evening
Source: A. Steptoe et al. (2004), Psychosomatic Medicine, 66: 323-329.
Inflammatory response (CRP) during experimentally
induced mental stress according to level of effortreward imbalance (N=92)
0.12
CRP change#
(μg/ml) as
function of effortreward imbalance
p < .05
0.10
0.08
0.06
0.04
0.02
#
adjusted for age,
BMI, baseline levels
0.00
low
medium
high
effort-reward imbalance
Effort-reward imbalance and affective disorder
(GHQ): Whitehall II-Study (odds ratios#; N=6110,
follow-up: 5.3 years)
3
2,5
*
men
women
2,5
*
2
2
1,5
1,5
1
1
0,5
0,5
low effort, high effort or
high reward low reward
#
3
high effort
and low
reward
*
low effort, high effort or
high reward low reward
adjusted for age, employment grade, baseline GHQ score
Source: S.A. Stansfeld et al. (1999), Occup Environ Med, 56: 302-7.
high effort
and low
reward
Cumulative work stress and reduced mental health
(SCL-90): Belgian Somstress-Study (N=920, 1 yr.)
somatisation
% 50
40
30
20
10
0
anxiety
depression
t1 no t2 no
t1 yes t2 no
t1 no t2 yes
t1 yes t2 yes
effort-reward imbalance
Source: I. Godin et al. (2005), BMC Public Health, 5: 67.
Work stress (ERI), occupational position and
depression (HNR Study; baseline; N=1811 men and
women aged 45-65)
Odds ratio
8
7
Risk of depression
6
Synergy index: 1.99 (1.02-3.85)
*
5
4
*
3
2
1
0
low ERI / high
position
low ERI / low high ERI / high high ERI / low
position
position
position
Source: N. Wege, N. Dragano, J. Siegrist (2008) JECH 62: 338-341
Morning cortisol after dexametason-test in teachers
with or without work stress (N=135)
Source: Bellingrath S et al (2008) Biol Psychol 78: 104-113
Work stress (ERI) and natural killer cells in 347
Japanese employees
Source: Nakata A et al (2011) Effort-reward imbalance, overcommitment, and cellular immune
measures among white-collar employees. Biol Psychol [in press]
The social gradient of work stress in the European
workforce (age 50-65): SHARE-study
Social gradient of work stress
40
Percent high stressed
35
30
Very low
25
Low
20
Medium
High
15
Very high
10
5
0
Effort-Reward Imbalance
Low control
Source: Wahrendorf M et al. 2011 (unpublished results based on SHARE release 2.3.0)
10% 20% 30% 40% 50% 60% 70% 80%
desire for early retirement
Work stress (effort-reward imbalance) and the desire
for early retirement (SHARE Study; N=6,524)
ES
FR
IT
AT
GR
high work stress
low work stress
Source: Adapted from Siegrist et al. (2006). EJPH.
DE
SE
DK
CH
NL
medium work stress
Increasing relevance of work stress in rapidly
developing countries due to globalisation
• First studies applying the ERI-model in
China, Taiwan, South Korea and Brazil
Reduced health functioning in Chinese
physicians (Li et al. 2006)
Elevated risk of menstrual disorders in Chinese
railway workers (Zhou et al. 2010)
Elevated risk of depression in Taiwanese
engineers (Chen et al. 2010)
Reduced health functioning in blue collars in
South Korea (Eum et al. 2008)
Psychosocial stress at work in Chinese male
coronary patients vs. healthy controls (N=388)
6
5
4
low
middle
high
3
2
1
0
Effort-Reward Imbalance
Adjusted for age, and sex; Additionally adjusted for hypertension, diabetes
mellitus, smoking, BMI, CHD family history, educational level, and marital status;
*p<0.05; **p<0.01; ***p<0.001
Source: Xu W. et al (2009) J Occup Health 51: 107-113
Psychosocial stress and hypertension among
working women in Beijing (N=421 ♀; 38,88,1 y.)
Multivariate prevalence
odds ratio of hypertension
Low reward
Low job variety
Conflict between work
and family
Smoking
BMI ≥ 25
3.09 (1.21 - 7.92)
3.05 (1.49 - 6.27)
3.79 (1.19 - 3.95)
2.17 (1.19 - 3.90)
7.29 (3.71 - 14.37)
Source: L.Y. Xu et al. (2000), Int J Behav Med, 7, S1: 10.
School stress (ERI-S) and poor self-rated
health in Chinese students
3,5
3
2,5
2
ERI-S low
ERI-S middle
ERI-S high
1,5
1
0,5
0
Boys
Girls
N=1004 boys and girls; mean age: 15.9 +/-2.5: OR adj. for age, grade, health
behaviours, family wealth
Source: J. Li et al. (2010) J Epidemiol 20: 111-118.
Work stress and poor self-rated health among
Brazilian nurses in public hospitals (n=1307)
3
2,5
2
1,5
ERI- and OCERI+ and OC+
DC- and SocS-
1
0,5
DC+ and
SocS+
0
•
•
Odds ratios* of poor self-rated health among nurses in public hospitals
* adj. For age, education, work contract, nr. of jobs, physical activity, smoking,
alcohol
Source: R. Härter Griep et al. (2011) Rev Saúde Publica 45:1-8.
Summary:
Main features of health promoting work
• Challenging task profile providing autonomy,
control and opportunities of personal
development
• Appropriate material and non-material
rewards in return to accomplished
achievements
• Trusting, fair and supportive relationships at
work
• Meaningful and secure employment
Evidence-based policy interventions at
different levels
Legislation, Regulation,
Social movements
Employer initiated new
systems of work organization,
Collective bargaining
Employer initiated job redesign,
Labor-management committees,
Action research
Economic, political context
Organizational context
Job insecurity, Downsizing
Precarious work
New systems of work organization
Job characteristics
Low job control / reward
High job demands / effort
Stress response
Health promotion,
Stress management
Treatment, Rehabilitation,
Return-to-Work programs
Physiological effects (e.g., BP )
Psychological effects (e.g., burnout)
Health behaviors
Illness
Structural intervention at the level of single
organisations: demand-control model
 Job enrichment
 Job enlargement (decision, control, responsibility)
 Tasks with enhanced skill utilization / active learning
 Increase of participatory activities
 Strengthening social support at work
 Extensive job training, requalification
 Reduced status differences, flat hierarchies
Structural intervention at the level of single
organisations: effort-reward imbalance model
 Compensatory wage differentials
 Models of gain-sharing
 Flexible time arrangements
 Incentives for esteem / recognition
 Enhanced leadership skills (managers)
 Promotion prospects according to achievements
 Extensive job training / requalification
 Job security
Work stress and health problems after structural
intervention*
Means at t1 adj. for t0
Variable
Demand
Control
Supervisor support
Coworker support
ERI
Psychol. distress
Work-rel. burnout
experimental - control hospital
12.08
68.59
10.82
12.49
1.10
21.17
46.66
12.68
68.06
10.42
12.26
1.15
22.43
49.03
p
.015
.382
.028
.056
.002
.205
.034
*12 month-follow-up, two Canadian hospitals, N=302 (intervention) vs. 311 (control
hospital) (ANCOVA, adj. for baseline values)
Source: R. Bourbonnais et al. (2006), Occup Environ Med, 63: 335.
Seven practices of successful organizations:
reconciling health promotion with economy
1. Employment security
2. Selective hiring of new personnel
3. Self-managed teams; decentralization of decision
making
4. Comparatively high compensation contingent
on performance
5. Extensive training
6. Reduced status distinctions and barriers
7. Extensive sharing of financial and performance
information
Structural interventions at national level:
welfare state labour and social policies
• Hypotheses:
– Mean level of stressful work and employment is
lower in countries with well developed welfare
state labour and social policies than in countries
with neoliberal policies.
– Reduced mean level of work-stress in these
countries goes along with a reduced burden of
work-related diseases.
• Cross-national multilevel analyses of comparable
data sets (SHARE, ELSA, HRS)
Macro indicators of national labour and social policies
and mean level of work-stress in 13 European
countries (SHARE study)
Macro indicator: Percentage of workers participating in further education.
Source: Siegrist J., Wahrendorf M. (2011) in: The Individual and the Welfare State (ed. A.
Börsch-Supan et al.) Springer Heidelberg
Macro indicators of national labour and social policies
and mean level of work-stress in 13 European
countries (SHARE study)
Macro indicator: national
expenses on rehabilitation
services as % of GDP.
Source: Siegrist J., Wahrendorf M. (2011) in: The
Individual and the Welfare State (ed. A. BörschSupan et al.) Springer Heidelberg
Effort-reward ratio (country) and women‘s
employment rate (18 countries study)
Source: unpublished findings
T. Lunau, N. Dragano, J.
Siegrist (2011)
Effects of stressful work on depressive symptoms:
variation according to welfare system (SHARE)?
3
Odds ratio
2
no
yes
1
0
social
democratic
conservative
liberal
Effort-Reward imbalance
social
democratic
conservative
liberal
Low conctrol
Stressful work: Tertiles, effort-reward ratio or low control
Depressive symptoms: Odds ratios adjusted for SEP, age and gender.
Source: Dragano N et al (2011) J Epidemiol Community Health 65: 793-799.
Policy recommendations at
national/international levels I
• Invest in human capital and additional active
labour market policies to improve quality of
work and employment
• Increase employment protection by
legislation/regulation prioritising vulnerable
groups, and by providing high quality
occupational safety and health services
• Strenghten primary prevention and establish
national monitoring and risk management
systems
Policy recommendations at
national/international levels II
• Develop international networks to face
global economic/financial and ecological
threats (e.g. WHO, ILO, EU-OSHA)
Rio Political Declaration on Social
Determinants of Health (21 October 2011)
„Strengthen occupational health safety and health
protection and their oversight and encourage the
public and private sectors to offer healthy working
conditions so as to contribute to promoting health for
all.“
Thank you!