Work, stress, and bodily
reactions
Åse Marie Hansen
National Research Cent re for the
Working Environment
Work, stress, and bodily
reactions
•
•
•
•
•
What is stress?
How to measure stress?
The bodily reaction to workrelated stress?
When is stress unhealthy?
Biological variation
Model
Exposure
Effect
Biological response
Concept of biomarkers
Stressor
Individual factors
Perceived psykosocial
work environment
Acute physiological response
Long term effects
Strain
Train
What is stress?
Example:
Stress is a series of reactions, which may
lead to a chroni c individual state
characterized by a combination of high
arousal, aversion and negati ve
expectation about sol ving the challenge
What is stress?
Stress is your body's way of responding to any kind
of demand. It can be caused by both good and bad
experiences.
Stress is the emotional and physical strain caused
by our response to pressure from the outside world.
What is workrelated stress?
Stressors at the work place
Chemical exposure
Job control
Job demands,
heavy work load
Physical work place
e.g. noise and temperatur
Job demands,
mental demands
Physical strain
Reactions to stress
• Cognitive and emotional reactions
• Behavioral reactions/symptoms
• Somatic reactions
• Physiological reactions
Cognitive and emotional reactions
Anxiety
Irritability
Lack of motivation
Tiredness
Difficulty to remember
Difficulty to concentrate
Depression
Low self-worth
Behavioral symptoms
Lack of appetite
Sleep problems
Reservation
Aggression
Low performance
Anger
Behavioral reactions to stress
Physical activity
Sick leave
Indecisive
Alcohol
Coffee
Smoking
Abuse
Somatic symptoms of stress
Stomach problems
Loss of weight
Palpitation/ Pain in the breast
Headache
Sweating
Often infections
Hyperventilation
How to measure stress?
• Questionnaire, e.g.
–
–
–
–
Demand/control
Effort /reward
COPSOQ
Perceived stress and energy
• Observations
• Bodily reactions to stress
(physiological reactions), e.g.
– cortisol in saliva
– adrenaline and noradrenaline in urine
How do you feel after a normal
workday?
Not at
all
Very little
To some
degree
Sometimes
Often
S: Refreshed
E: Active
S: Tense
E: Sad
S: Stressed
E: Energetic
E: Ineffective
S: Relaxed
E: Focused
S: Pressure
E: Passive
S: Calm
Translated from Kjellberg and Iwanowski 1989
Very
often
Responses from approx. 600
officeworkers
Not at
all
Very little
To some
degree
Sometimes
S: Refreshed
17 %
S: Relaxed
5%
x
1,5 %
x
S: Calm
Often
Very
often
x
S: Tense
x
15 %
S: Stressed
x
15 %
S: Pressure
x
14 %
E: Active
2%
E: Energetic
3%
E: Focused
5%
E: Sad
x
x
x
x
3%
E: Ineffective
x
5%
E: Passive
x
5%
Stress scale = 2.3 Energy scale = 3.0
Time
00:00
18:00
Saturday
12:00
06:00
00:00
18:00
Friday
12:00
06:00
00:00
Thursday
18:00
12:00
06:00
00:00
Wednesday
18:00
12:00
06:00
00:00
18:00
Tuesday
12:00
06:00
00:00
18:00
2.5
12:00
06:00
00:00
Stress Index Score
Stress index
Sunday
2.0
1.5
1.0
0.5
0.0
Time
00:00
18:00
Saturday
12:00
06:00
00:00
18:00
Friday
12:00
06:00
00:00
Thursday
18:00
12:00
06:00
00:00
Wednesday
18:00
12:00
06:00
00:00
18:00
Tuesday
12:00
06:00
00:00
18:00
5.0
12:00
06:00
00:00
Energy Index Score
Energy index
Sunday
4.0
3.0
2.0
1.0
0.0
How the body responds to
work-related stress
The sympat hetic nervous
system
•
Adrenaline /noradrenaline increase
•
Heart frequency increase
•
Blood pressure increase
•
More blood to the muscles
•
Less blood to the skin
•
Low digestion
•
Increased brain activity
Biomarkers for catabolic
and anabolic metabolism
Catecholamines
(adrenaline and
noradrenaline)
Cortisol
Glycated hemoglobin
(HbA 1c)
Testosterone
Growth hormone
Dehydroepiandrosterone
(DHEA)
% of pre-overtime value
Unwinding after work overload
250
200
150
Hours
100
18
12
6
0
50
0
0
5
10
15
20
Weeks
Evening
Daytime
Extra working hours
Frankenhaueser and Johansson. Int.Rev.Appl.Psychol. (1986)
Total serum cholesterol
mg/100 mL plasma
B
A
A and B
B
240
235
230
225
220
215
210
205
200
31
6
-5
2
1
20
7
-5
1
0
7
5
20
09
01
7
-5
3
0
7
5
30
21
7
7
7
7
7
-5
-5
-5
-5
-5
4
4
5
6
6
-0
-0
-0
-0
-0
10
30
20
09
29
Group A
Perceived stress
Group B
Friedman et al. 1958
Noise
Cortisol (mgram/mg creatinine)
0.090
0.080
Without hearing protection
With hearing protection
0.070
0.060
0.050
06:00
08:00
10:00
12:00
14:00
Melamed et al., Psychom.Res.1995
Monotonous work
HbA1c
1
Kolesterol
DHEA-S
Testosteron
IgA
Prolaktin
Adrenalin
Noradrenalin
Kortisol
Helbredsundersøgelse
Generelt stress niveau
Oplevet situation
Hansen et al 2003
Job strain and HbA 1c
% of total hemoglobin
4,75
*
* p<0.05
4,70
4,65
4,60
4,55
4,50
low demand/
low demand/
high demand/
high demand/
low control
high control
low control
high control
Unpublished results
Outsourcing
Outsourcing
DHEA-S
HbA 1c
**
Cortisol
*
Noradrenaline
Adrenaline
-20
0
20
40
60
Percent increase
Netterstrøm et al. (2000)
Threat of closing
Norwegian metal workers
(N = approx. 180)
BP (mm Hg)
160
150
140
130
120
110
100
90
80
Pulse
80
78
145
143 76
142
SBP
135
74
130
129
129
70 72
69
70
68
Pulse
66
63
63
96
64
94
91
90
62
86
85
84
DBP 60
58
1982 1983 1984 1985 1986 1987 1988
Erikssen et al. 1990
Organisational downsizing and
death
7,5 years follow-up study among 22.430 employees
in the public sector, who kept their jobs
RR*
Other
deaths
CVD
2.0
2.02
1.5
1.2
1.01
0
1.0
1.0
None
1.2
Minor
Major
None
Minor
Major
Extent of downsizing
*Controlled for age, gender, SES og job
Vahtera et al. BMJ 2004;328:555-558.
When are the physiological
reactions unhealthy?
Models for health risk
•
•
•
•
•
Cognitive activation theory
Allostasis
Lack of restitution
Shift of rhythms
Stress-disequilibrium theory
(Not included)
Cortisol in saliva (nmol/l)
Bullying and cortisol in saliva
19.00
15.00
11.00
7.00
3.00
00:00
06:00
12:00
18:00
Time of day
Reference group
bullied individuals
00:00
Allostasis
The ability to
achieve stability
through change.
Size of response
Allostatic load
The wear and
tear that result
from chronic
overactivity or
underactivity
of allostatic
systems
Exposure
McEwen New England Journal of Medicine (1998)
Successful aging
•
•
•
•
•
•
•
•
•
•
Systolic blood pressure (>148 mm Hg)
Diastolic blood pressure (>83 mm Hg)
Waist-hip ratio (>0.94)
Total cholesterol-HDL ratio (>5.9)
Total HbA1c (>7.1%)
Urinary cortisol (>25.7 mg/g creatinine)
Urinary norepinephrine (>48 mg/g creatinine)
Urinary epinephrine (>5 mg/g creatinine)
HDL cholesterol (< 1.45 mmol/L)
DHEA-S (<2.5 mmol/L)
T.E. Seeman et al. (1997)
New cardiovascular disease, %
Successful aging
15
10
5
0
0
1-2
>=3
Allostatic load category
T.E. Seeman et al. (1997)
Cortisol and memory
12
No. of correctly recalled words
10
8
6
4
2
0
-10
-5
0
5
10
15
20
25
Cortisol response (nmol/L)
Kirschbaum et al. Life Sci. 1996
No. of recalled or completed words
Cortisol and memory
9
*
8
10 mg cortisol
Placebo
7
6
5
4
3
2
1
0
Declarative memory
Procedural memory
Kirschbaum et al. Life Sci. 1996
Cortisol and memory
Immediate recall bits
65
60
55
placebo
40 mg/d
160 mg/d
50
45
0
2
4
6
8
10
Days
Newcomer et al. Arch.Gen.Psychiatry 1999
Rate of recovery
Exposure
Unwinding after work overload
% of pre-overtime value
of epinephrine
250
200
150
Hours
100
18
12
6
0
50
0
0
5
10
15
20
Weeks
Extra working hours
Daytime
Evening
Frankenhaueser and Johansson. Int.Rev.Appl.Ps ychol. (1986)
Reduced reactivity
Stressor
Serum cortisol (nmol/L)
Serum corti sol after stress test
500
Stress test
***
***
*
450
Vilnius
400
Linköping
Base
16
20
30
40
Minutes after stress test
M. Kristensson et al. (1998)
Lack of variability
High
Flat
Normal
Construction workers
Cortisol in saliva during a
working day
25.00
Reference group
20.00
Construction workers - normal day
Construction workers - long day
nmol cortisol/l saliva
Significantly
higher concentration of saliva cortisol observed in
15.00
construction workers compared to reference group. No difference was
observed between
construction workers having long and normal days
10.00
5.00
0.00
03:00
09:00
15:00
21:00
Time (hours)
Hansen, 2006
Relative variability in salivary
cortisol
Construction workers
Long days
CV (%)
CI (%)
#
CV (%)
CI (%)
*
*
#
*
Reference group
P-value
76
99
0.004
[65-92]
[91-108]
Normal days
82
72
99
[64-112]
[57-95]
[91-108]
Coefficient of variance
Confidence interval
# 95%
Hansen, 2006
0.043
Conclusion
• Construction workers had higher
concentrations of cortisol in saliva
during a work da y compared to white
collar workers.
• Construction workers had lower relative
variability in cortisol compared to whi te
collar workers
Restitution
Catabolic metabolism
Anabolic metabolism
Demands
Rest
Demands
Restitution
Catabolic metabolism
Anabolic metabolism
Demands
Rest
Demands
Outsourcing
DHEA-S
HbA 1c
**
Cortisol
*
Noradrenaline
Adrenaline
-20
0
20
40
60
Percent increase
Netterstrøm et al. (2000)
Risc of increased blood pressure
Working hours and blood
pressure
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
11-39
40
41-51
> 51
Weekly working hours
Contolled for diabetes, tobacco, physical activty, SES, gender, age
(n=24.205, 18-64 år)
Yang et al. 2006
Øresundsbron
Building the bridge between
Sweden and Denmark
Testosterone (nmol/L)
22
20
18
Pylon workers
Controls
16
14
0
5
10
Days
Ørbæk et al. 2000
Øresundsbron
Exhaustion
15
% of the day
10
5
0
0
5
10
Dag
Pylon workers
Track workers
Ørbæk et al. 2000
15
Typical sleep
Gerlach: Søvn, 2003
Hormones respond to sleep
Sleep ® hormones:
Hormones ® sleep:
• Growth hormone,
prolactin and
testosterone • Thyroid hormone
and adrenaline ¯
• Cortisol - during
terminal sleep
• CRH reduces sleep
quality
• Melatonin stimulates
sleep
Stress and sleep
Stress
Physiological
arousal
Need for
increased effort
Increased cortisol
and adrenaline
Sleep loss
Difficulties
falling asleep
Sleep problems -> illness
• Increased risk of heart disease
– Review of 10 studies
– High quality studies found increased risk of
coronary events after adjusting for age and other
risk factors
– The combined risk was 1.7 (range 1.5 -3.9)
• Increased risk of diabetes
– 6599 non-diabetic men at baseline, aged 44.5 ±
4.0 years
– 281 (4.3%) developed diabetes during follow-up
(14.8 years)
– Men with difficulties falling asleep or regular use of
hypnotics had increased risk of 1.52 [95% CI:
Schwarts S et al., J Psychosom Res, 1999
1.05-2.20]
Nilsson PM et al., Diabetes Care, 2004
Sleep and heart disease
A study of 71,617 American nurses f ollowed for 10 years
2.0
Adjusted for 14 factors
Age-adjusted
2.5 RR
1.8
1.6
1.5
1.4
1.3
1.1
1.0
1.4
1.2
1.0
1.1
1.0
0.5
0.0
-5
6
7
8
9+
-5
6
7
8
9+
Ayas et al. Arch Intern Med 2003;163:205-9. The Nurses’ Health
Study
Psychosocial work and sleep
Increases
sleep problems:
• High demands
• Low control
• Keep thinking of
work
• Expect difficult
workday
• Unsolved conflicts
• Unsolved problems
Decreases
sleep problems:
• Social support
Kalimo et al., Stress Med, 2000
Åkerstedt et al., J Psychosom Res 53(1), 2002
Åkerstedt et al., J Psychosom Res 53(3), 2002
Kecklund et al., Biol Psychol, 2004
Shift of rhytms
18
Extremely sleepy
Sleepy
Neither alert nor sleepy
Alert
Very alert
06:00
12:00
18:00
24:00
Fixed shift night
16
16
14
14
12
12
10
10
8
8
6
6
4
4
2
2
0
0
06:00
Time
KSS - workday
KSS - day off
18
12:00
18:00
Time
Melatonin - workday
Melatonin - day off
Working hours
Hansen et al., 2006
Garde et al., unpublished data
24:00
mmol aMT6/mol creatinine
Fixed shift day
Biological variation
Biological variation
Physiological
Lifestyle
Age, sex, hei ght, health etc.
Smoking, alcohol, medicine etc.
Genetic
Metabolism & Genotype
Individual factors
Age
Gender
Body mass index
Age
Stevens, Wilson, et al. 1997
Age
DHEA (nmol/L)
40
Women
Men
30
20
10
0
19-39
40-49
50-59
>60
Years of age
AR Genazzani (1998)
Age and BMI
S-DHEA-S (nmol/L)
8
7
6
5
4
3
2
1
30
20
0
30
Age (years)
BMI (kg/m2)
60
Hansen et al 2002
Age and smoking
B-HbA1c (%)
5
4
Smoker
Non-smoker
30
Age (years)
60
Hansen et al 2002
Gender
Testosterone (nmol/L)
30
25
20
15
10
5
0
H Olesen et al. (1987)
Individual factors related to life
style
Coffee
Alcohol
Smoking
Medicine
Evening coffee steels your
sleep
One cup of coffee
contains enough
coffein to half the
amount of melatonin
Ingeniøren No 22, Maj 2002, (part of a note from New Scientist)
Urinary adrenaline: Smoking and BMI
Women BMI 19-20
Smoker
Non-smoker
5
4
3
2
1
0
05:45
11:45
17:45
Hour
23:45
6
µmol/mol creatinine
µmol/mol creatinine
6
Women BMI 28-30
5
Smoker
4
Non-smokers
3
2
1
0
05:45
11:45
17:45
Hour
Hansen et al. 2001
23:45
Genetic factors
Ethnic background:
20% higher levels of S testosterone in black subjects
% HbA1c lower in Caucasian
compared to black subjects
Other Interactions
Exercise
Food
Artificiel light
Wake up
Circadian rhytm
Seasonal variation
Circadian variation
Medicinsk Kompendium (1994)
Circadian variation
Plasma cortisol (nmol/L)
1000
750
500
250
0
12
16
20
24
4
8
12
Time
Medicinsk Kompendium (1994)
Seasonal variation epinephrine
µmol/mol creatinine
10
8
6
4
2
0
0
06.00
12.00
Hour
June and July
18.00
24.00
August to May
Hansen et al 2001
Seasonal variation
of DHEAS
9
Summer
Winter
Plasma DHEAS
(µmol/L)
8
7
6
5
4
June July Aug Sep
Oct
Nov Dec Jan
Feb Mar
Apr May
Garde et al, 2000
Within and between subject
variation
12
10
8
6
4
2
0
0
5
10
15
20
Plasma DHEA-S (mmol/L)
Garde et al, 2000
Within and between subject
variation
12
10
8
6
4
2
0
3.0
3.5
4.0
4.5
5.0
5.5
Blood HbA1c (% of total hemoglobin)
Garde et al, 2000
Questions?
• Åse Marie Hansen
aamh@arbej dsmiljoforskning.dk