1. SHIFT WORK & HEALTH
Dr Omid Aminian

2. Shift Work
Shift work involves work at times other than normal daylight hours 7:00 AM to 7:00 PM
10%-20% all workers are doing shift work
Night and shift work have been associated with:
Immediate risk to worker safety
Long term risk to worker health
Up to 20% of all worker are unable to tolerate working at night

3. Biologic Rhythms
Ultradian: frequency of less than one cycle every 20h for example REM
Infradian: periods greater than 28h for example menstural cycle
Circadian: oscillate with a frequency close the24h for example body temperature
Human biologic rhythms have a 25h cycle

4. Human variable observed to follow a circadian rhythms
Body temperature
Serum corticosteroids & electrlytes
Cardiovascular functions
Gasteric enzyms secretion
Leukocyte count
Muscle strength
Alertness & mood
Immediate & long term memory

5. Shift lag - Dyschronism
Strong circadian control:
Body temperature
Hypothalamic –pituitary-adrenal axis
Weak circadian control:
Sleep-wake cycle
Dyschronosis:
Disruption of the circadian system

6. Sleep Deprivation
Sleep deprivation is the most significant complaint in shift work
About 62% of night worker complain sleep deprivation
Shift work affects not only sleep length but also sleep quality
REM decrease in the sleep after night work

7. Condition That May Be Exacerbate By Shift Work
Sleep disorder
Asthma
Coronary artery disease
Psychiatric disorder
Epilepsy
Gasterointestinal disease
Shift maladaption syndrome
Long-term drug therapy

8. Shift Work maladaptation syndrome
10%-20% all shift worker
Chronic sleep disturbance & fatigue
Gasterointestinal symptoms
Alcohol and drug abuse
Depression
Difficult inter personal relationships
Use of sleeping pills
Higher accident

9. 40,000,000 Americans suffer from sleep disorders that effect the quality and quantity of their sleep.
Only 35% of adults sleep the recommended 8 hours or more per night during the work week.
56% of adults report symptoms
of insomnia a few nights a week.

10. Common Negative Effects of Shift Work
Lack of Communication between staff on different shifts.
Lack of “Teamwork”.
Lack of concentration while on duty.
Potential Unsafe Conditions.
Stress/fatigue.
SHIFT LAG.

11. Shift Lag Mental Symptoms Physical Symptoms
Increased Irritability-Stress-Forgetfulness
Psychiatric disorder
Physical Symptoms
Sleep disorder-Coronary artery disease- Gasterointestinal disease- Shift maladaption syndrome-Reproductive effects