Life cycle analysis of noise and hearing handicap in Finland

1
Life cycle analysis of noise and hearing handicap
in Finland

• Esko Toppila1, Ilmari Pyykkö2,
• Rauno Pääkkönen1
• 1Finnish Institute of Occupational Health
• 2University of Tampere

2
Noise and Work

Military branch
Industry

Services
Schools
Environment
Communication
Hearing loss
Annoyance
3
Characteristics of work in 20th century (Ruben
2000)
4
Hearing handicap

• Symptoms
• hearing loss
• hyperacusia
• difficulties in sound localisation
• tinnitus
• reduced speach intelligibility especially in
  ambient noise
• diplacusis
• --.
• Symptoms start typically in age of 45
• First affect in poor acoustical conditions

5
Classification of hearing handicaps

• Non-noise induced (gt10 of people under 65)
• Presbyacusis
• Often genetic background
• CNS infection, ear infection
• sociocusis
• Middle ear problems (seldom)
• Noise induced (lt10 of workers in noise over 85
  dB)
• Acute trauma
• Chronic trauma (The "real" hearing handicap)
• Evaluation based on audiogram
• Tinnitus .. do not affect typically

6
Social effects of hearing handicap

• Reduced speech intelligibility
• Do no understand especially in ambient noise
• Social isolation
• Mental problems (. 2x)
• Tendency to believe that others make fun
• Increased accident risk
• Misunderstanding instructions
• Failure to hear warning signals
• Reduced career opportunities
• Training difficult speech
• is not understood
• Increased risk of unemplyoment
• " dumb people do not work here"
• Reduced capability to localize sounds
• Increased accident risk
• if moving machines around
• Reduced speech intelligibility

7
Social effects of hearing handicap

• Tinnitus
• Increased annoyance
• may interfere with warning signals
• sleep disturbance
• avoidance of social noisy events
• concerts, public events,.
• Hyperacusia
• stress
• avoidance of social noisy events
• concerts, public events,

8
Self evaluated hearing
Normal

Mild
Moderate
9
Quality of life and self-evaluated hearing
80
70
60
50
EQ-5D thermometer
40
30
20
1
15
161
257
147
N
Deaf
Some difficulties
Normal
almost deaf
Minor problems
Self-evaluated hearing
10
Effect of hearing in different populations
0.9
0.9
0.85
0.85
0.8
0.8
Normaali
Normal
0.75
0.75
Liev
ä
Mild
0.7
Kohtalainen
0.7
Moderate
Vakava
Almost deaf
0.65
0.65
0.6
0.6
0.55
0.55
0.5
0.5
Technicians
TAYSlt66
Laminoijat
Puusep
ä
t
Korkea
Users of hearing aids
Physical workers
High comm workers
Kommunikaatio
11
Life cycle of noise
(20-30 y)
(0-5 y)
(45-68 y)
-Exercise -Noise limits in discos -Teaching
attitudes
Accumulation of noise effects
Ambient noise Free time noise
- Vaccination - Personal pacifier
Nosocusis Discos and concerts Equipment
Earlier access to hearing aids
Life style Work noise

• Hearing protection
• Healthier life style

-Better hearing protection
Infections
Early retirement dementia
Ambient noise
-Personal hearing solutions - Office noise
Conscript noise
12
Estimates of the size of the problem

• Number of conscripts with hearing loss gt20 dB at
  any frequency has increased from 13 to 20
• Noise ?
• Life style factors (Young age cholesterol RR7.2,
  Pyykkö et al 2007)
• Kindergarten infections ?
• Call centers (Toppila et al 2008)
• 15 -25 complaints about hearing
• Demanding job -gt subclinical hearing loss
  important
• Protection against work noise not efficient
• In elderly people in noisy occupations
  overpresented in hearing aids fitting
• Factor 2

13
Size of problem

• Finland looses 21 B every year because of early
  removal from workforce (Ahonen, Vainio 2010)
• Hearing impairment seems to be involved in 5-15
  of the cases
• Annual cost 2.1 B (Extrapolated to US 176 B)
• Mostly from work not done
• Direct costs 200-400 M (Extrapolated to US
  2.5B)
• These calculations exclude
• Lost career opportunities
• Effect on pensionnaires
• earlier dementia etc.

14
Hearing loss, removal from workforce and
statistics (Total workforce 2.2 M)
Ei ty
ö
melua 1600 000
No worknoise 1600 000
2000
2000
Risk group
Unempolyment
for early removal from workforce 250 000
Toistuvat
Repeated
300
-
500
300
-
500
korvatulehdukset
infections
3000
3000
Vapaa
-
ajan
100
-
400
-
100
-
400
Free time
Early retirement
Melu
noise
300
-
500
300
-
500
30
-
40?
30
-
40?
Accident
Asevelvollisuus
Conscript noise
melu
500?
500?
1000
1000
Dementia
Nuoren i
ä
n
Young age
kolesteroli
cholersterol
lt10
lt10
Statistics
Stat
Ototoxic
130
Ototoksinen
130
l
ää
kitys
medication
NIHL
1000
1000
Riskitekij
ä
t
Risk factorsj
50
50
Hearing loss
Worknoise
700
700
0
0
Noise caused accident
70
Combined exposure
A
70
Chemicals, vibration, medication
Work noise 400 0000
15
Potential for savings

• Reduction of sociocusis, early age effects 30
• Reduction of Noise Induced Hearing Loss 70
• Not 100 because of overdiagnosis
• Totally in work force 35
• 750M/y (US 62 B)

16
Discussion

• Noise is underestimated problem in modern
  societies
• Affects people with hearing handicap in harsh
  communication environments
• Cause for underestimation
• Affects several factors
• Never the most important factor but ranked 3-5
  (de Hollander et al 1999)
• To reduce the adverse effects of noise
• work noise protection
• reduction of nosocusis
• protection of free time noise