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Tage S. Kristensen
Psychosocial DepartmentNational Institute of Occupational Health
Copenhagen, Denmark
27th International Congress on Occupational Health
Iguassu Falls, Brazil
L:\PSA01\8. PERSONLIGE ARKIVER\LNA\Forskere\Tage
ICOH-Symposium on Psychosocial Factors
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Cardiovascular mortality for Danish men.
FarmersArchitectsMilitary officersProfessorsGardenersDoctors
All employed men
JournalistsSailorsBus driversCooksWaitersSalvage corps driversRestaurant ownersTaxi drivers
676869717577
100
121122127135150150162185
SMR
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Heart disease and work
”Little is known about occupational risks
for coronary heart disease”
Kyle Steenland. NIOSH. Am J Ind Med 1996;30:495-9
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The connection betweenwork and CVD
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General model for the relationship between work environment and cardiovascular
diseases
WORKENVIRON-
MENT
CARDIO-VASCULAR DISEASES
CVD risk factors:Diet obesity,
blood pressure,smoking etc.
3
1 2
THE SIGNIFICANCE OF WORK: 1+3
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Work and deathHow many deaths are due to working conditions?
Men Women Total
Death, all causes 10% 2% 7%
Heart disease 19% 9% 17%
Stroke 12% 8% 11%
Cancer 14% 2% 8%
Respiratory diseases 7% 1% 4%
Accidents, violence 4% 0.4% 3%
All proportions apply to Finland
Nurminen & Karjalainen. Scand J Work Environ Health 2001;27:161-213.
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The impact of work on cardiovascular diseases
Etiologic fraction Men 16%
Women 22%
Etiologic fraction IHD 17%
Stroke 11%
Nurminen & Karjalainen. Scand J Work Environ Helath 2001;27:161-213.
Olsen & Kristensen. J Epidemiol Community Health 1991;45:4-10
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Empirical evidence
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Etiological fractions of work environment for cardiovascular diseases in Denmark
(Olsen & Kristensen. J Epidemiol Community Health 1991;45:4-10)
Proportion of CVD
Risk factor Men Women
”Sedentary” work 42% 42%
Job Stressors 6% 14%
Shift & night work 7% 7%
Noise 1% 1%
Chemical exposures 0-1% 0%
Passive smoking 2% 2%
All factors 51% 55%
All factors except sedentary work 16% 22%
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100
193215
168 172
0
50
100
150
200
250
Day Night Lateevening
24 hourrosters
Otherirregular
(4 years of follow-up. N=407,000)
Standardized Hospitalization Ratios (SHR’s) for IHD among Danish men aged 20-59 years
(Tüchsen. Int J Epidemiol 1993;22:215-21)
SHR
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Relative risk of IHD among shift workers15 years of follow-up
0
0,5
1
1,5
2
2,5
3
0 2-5 6-10 11-15 16-20 21+
Years of shift work
1
1.5
22.2
2.8
0.4
RR
(Knutsson et al. Lancet 1986;II:89-92
3
2.5
2
1.5
1
0.5
0
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Work noise and AMI
0
0,5
1
1,5
2
2,5
3
3,5
4
Type writer El. lawn mower El. drill Road drillNoise level:
OR (adjusted)
A case control study of 395 cases and 2,148 controls from Berlin.
Ising et al. Soz Präventivmed 1997;42:216-22.
1.0
1.4
2.0
3.84
3.5
3
2.5
2
1.5
1
0.5
0
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The two main psychosocial models on work and CVD
The job strain model
– demands– control– support
The effort reward imbalance model
– effort (extrinsic)
– rewards (money, esteem, career opportunities)– personality (instrincis effort – overcommitment)
Good – but not excellent – empirical support for the two models
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0
0,2
0,4
0,6
0,8
1
1,2
1,4
1,6
Hospital admission for CVD in a group of unemployed men compared with a control group
0.80
1.04
1.60
(Iversen et al. BMJ 1989;299:1073-6)
1.6
1.4
1.2
1
0.8
0.6
0.4
0
RR
0.2
Beforefactory closure
(2 years)
Duringfactory closure
(3 years)
Afterfactory closure
(3 years)
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Issues in research
and prevention
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The cardiovascular tradition from Framingham and onwards.
Physiological:
• Cholesterol
• Fibrinogen
• Triglycerides
• Glucose
• Blood pressure
• Heart rate
• Obesity
Behavioral:
• Smoking
• Physical inactivity
• Type A
• Salt intake
• Diet
• Alcohol
Risk factors are individual.
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The individualistic bias of cardiovascular epidemiology and prevention
Sampling: Representative samples of individuals
Variables: Physiological and behavioral factors
Risk factors: Individual characteristics (e.g. high cholesterol) or behaviors (e.g. smoking)
Preventionstrategies: Interventions aiming at the individual:
High risk intervention or mass intervention
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The missing connection between cardiovascular and occupational medicine
Occupational medicine
focuses on:
Cancer Lung diseases Musculoskeletal disorders Reproductive disorders Allergies– but not CVD
Preventive cardiology
focuses on:
Tobacco Cholesterol Blood pressure Physical activity Diet– but not work environment
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The basic dimensions of stressors at work
The ”Copenhagen Stress Model”
• Influence (with regard to the conditions of daily work)
• Meaning(purpose and connection to the overall production)
• Predictability(relevant information about future changes and events)
• Social support(from supervisors and colleagues)
• Rewards(salary, appreciation, and possibilities for a good and secure future)
• Demands(quantitative and qualitative)
Kristensen. Scand J Work Environ Health 1999;25:550-557.
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Topics for future research
Human service work:
New organisations:
Unstable labour markets:
Emotional demands
Burnout fatigue
CVD
Work without limits
Workaholism
CVD
Downsizing, unemployment, temporary work
Uncertainty, stress
CVD
?
?
?
?
?
?
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Causal network for CVD
Social &Environmental
FactorsBehavior Physiology Precursors
Individual
characteristics
Upstream
Downstream
Tobacco
Job strainPhysicalactivity
Fitness CholesterolAthero-sclerosis
Social isolation
ObesityBlood
pressureThrom-
bosis
Unem-ployment
Diet Type A FibrinogenArr-
hythmia
Noise Alcohol Stress GlucoseECG-
changes
SES&
OccupationCVD
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Integrated prevention at the workplace
Healthpromotion
Workenvironment
improvementsWorkplace
rehabilitation
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This presentation can be found at:www.ami.dk/presentations