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April 2015 | Read this issue and more at www.healthandwellnessmagazine.net |
Shift and Extended
Work Can
Compromise Health
By Angela S. Hoover, Staff Writer
Traditional work hours is defined
as working no more than 48 hours
averaged over a 17-week period, with
a minimum daily rest period of 11
consecutive hours and a minimum
weekly rest period of 24 or 48 consecutive hours averaged over 14 days.
It also entails a minimum of 20 minutes of rest during a work period of
more than six hours, with a maximum
of eight hours of night work every
24 hours as averaged over a 17-week
period.
Shift work, on the other hand,
consists of six to 12 hours of consecutive work with the shift crew
alternating on two, three or four shifts
in any 24-hour period. Groups of
people, such as bakers, have always
worked non-traditional hours. Yet
as the economy has become more
service based, more and more groups
are working second and third shifts.
Additionally, society’s need for emergency medical services, the technical
need for maintaining continuous
process industries and the economic
need for offsetting plant obsolescence
has contributed to the increase in
shift and extended work, according
to occupational health research-
ers. Today, more than 2 million
Americans work shift and/or extended work periods, says the Bureau for
Labor Statistics.
These groups of workers experience many difficulties in terms of
their family and social lives. And it
has been found that working shift
and extended work – especially over
long periods of time – has harmful
physical and mental effects. Extensive
publications expound the health and
social impacts of shift and extended
work.
J.M. Harrington of the Institute of
Occupational Health at the University
of Birmingham published a survey on
shift work and health based on more
than 30 other researchers’ work. The
researchers linked shift and extended
work with health issues. Harrington’s
survey found consistent results for
reduction in the quality and quantity
of sleep; fatigue; anxiety; depression;
increased neuroticism; an increase
in cardiovascular conditions; and a
possible increase in gastrointestinal
disorders.
The first aspect to consider with
shift and extended work is the effect
they have on the circadian rhythm.
Circadian rhythm is the body’s natural time-keeping system that influences body temperature, respiratory
rate, urinary excretion, cell division,
sleep and wakefulness and hormonal
changes. It helps the body and brain
function at their highest levels.
Circadian rhythm is generally measured by the length of a day because
most mammals, including humans,
operate on a 24- to 25-hour clock.
For humans, work occurs during the
day and rest happens in the evening.
Under normal conditions, the human
body temperature peaks in the late
afternoon and is the lowest in the
early morning hours. The circadian
rhythm can be reset by light and dark
cycles, social climate and work schedules. Many physiological problems
arise when working, eating and sleeping phases are changed. Disruption of
circadian rhythm has been linked to
breast cancer, cardiovascular disease,
reproductive difficulties and ulcers.
Not only does the disruption of the
circadian rhythm present its own set
of detrimental health effects, it also
opens the door for more physical,
mental and emotional health risks.
Fatigue and sleep issues are examples
of this domino effect. Shift and
extended work negatively impact
sleep, as does a disrupted circadian
rhythm. Sleep deprivation and sleep
quality and the resulting fatigue is
doubly effected for these workers.
Sleep issues and fatigue then cause
a whole host of other physical and
mental problems.
Sleep loss is one of the major
effects of shift work. The quantity
of sleep is generally reduced by up
to two hours a day. There is also an
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effect on the quality of sleep. Rapid
eye movement (REM) sleep and
stage 2 sleep are also reduced. Both
these sleep phases are of paramount
importance to overall health. Not
only does sleep loss cause fatigue, but
it can also be the precursor to accidents, mistakes and inefficient work.
Numerous Scandinavian studies
show shift workers have a 40-percent
increase in risks for cardiovascular
disorders, most notably angina pectoris, hypertension and myocardial
infarction. A mortality study from
California showed rates of arteriosclerotic heart disease in male
occupational groups increased in the
populations that worked more than
48 hours a week. These cardiovascular conditions are most likely caused
by circadian rhythm disruption, disturbed socio-temporal patterns, lack
of social support, stress, smoking,
poor diet and lack of exercise – all of
which shift and extended work can
cause and exacerbate.
Chinese researchers at the School
of Public Health at Tongji Medical
College, Huazhong University
of Science and Technology and
the School of Economics and
Management at the Jiangxi Science
and Technology Normal University
conducted a meta-analysis on observational studies involving shift work
and diabetes mellitus. They found
all shift work schedules (with the
exception of mixed shifts and evening
shifts) were associated with a statistically higher risk for diabetes than traditional daytime schedules. They also
found a stronger association between
shift work and diabetes for men than
for women.
Another major complaint of
shift workers is digestive disorders.
The same causes for cardiovascular
conditions can also be contributed
to gastrointestinal disorders. Night
workers in particular have the most
complaints of dyspepsia, heartburn,
abdominal pains and flatulence.
Another study in 2014 found a link
between circadian rhythm disruption
and inflammatory bowel disease and
related conditions.
Other research published
in the journal Occupational &
Environmental Medicine looked
at the health impact of performing shift work for 10 years or more.
Researchers found it had a strongly
negative effect on brain health. These
effects can be reversed, but full
recovery could take as long as five
years. Participants who had worked a
rotating shift for 10 years or more had
lower overall cogn ]]