Effect of shiftwork on sleep vigilance and efficiency at workplace

in Sleep Research and Insights


Fellow research review of: effects of shift work on subjective and objective sleep, vigilance, and efficiency of health caregivers. A research conducted Saranea Ganesan, Michelle Magee, Julia E. Stone, Megan D. Mulhall, Allison Collins, Mark E. Howard, Steven W. Lockley, Shantha M. W. Rajaratnam & Tracey L. Sletten



  • A study was conducted to determine the relationship between shiftwork and sleep quality. 52 healthcare workers participated in providing information on how shift work (which includes the morning, afternoon, and night shifts) affected their level of vigilance and efficiency at the workplace. Two major methods were implemented for the test; (Karolinska Sleepiness Scale, KSS) and Psychomotor Vigilance Test (PVT) experiments were used for the day shift, and the first and following night shift, which is the 3rd, 4th, or 5th days. The Circadian rhythm was evaluated with the usage of 6-sulfatoxymelatonin rhythms.

  • The extent of reaction was more with the PVT and KSS test at the first and successive night shifts. KSS showed the highest impact at the end of the first night shift. There is a greater effect on the reduced work output for the day shift due to previous night shifts. The distorted sleep-wake circadian rhythm is responsible for a reduction in work efficiency. Sleep is a physiological state of unconsciousness, which serves as a means to rest and help to restore and revitalize the weak body systems. Therefore, less sleep at night leads to poor outcomes for the day's work. This is particularly noticeable in the healthcare sector.

  • Health care workers are the backbone for the wellness of society. Errors in the dispensation of services could deal a fatal blow to the entirety of the world. Health care services are round-the-clock work; hence, the need for shift works. This shift work poses a serious challenge to health caregivers. The irregular work hours cause sleep disturbance that can lead to fatigue in delivering proper care. Night shift has a significant effect on the workers, as they stay awake to care for the patients. This takes a toll on their sleep quality. There is also a disruption in daytime activities. myAir app helps to monitor the rate of stress and sleep disturbances. This provides information that can help health care workers cope better. myAir also helps with tips to deal with stress and uses nutritious diets and clinically proven drugs to help.


The research shows that health care workers who worked night shifts experience sleep disturbance and reduced dispensation of services at work. The experiment involves both day and night shifts in which those that undergo more night shifts show more sleep deprivation, high level of stress, and circadian disturbance. It was observed that more effect was felt after the first night and later more pronounced at subsequent night shifts. In addition, long hours of service, like the extension of a night shift to the morning shift can increase the susceptibility of accidents and self-injury later on. The test showed that restrictions towards sleep occur most between successive night shifts (5.74 ± 1.30 h), succeeding day shifts (5.83 ± 0.92 h), and amidst evening and day shifts (5.20 ± 0.90 h) in the 24 hours daily.


Improving health care is important to sustaining any community. Hospitals are employing more health caregivers to attend to the large population seeking care. Several policies are available to improve the care that the public receives. Health caregivers ensure patients receive quality care. However, it is vital to remember that health caregivers are humans. They have emotions and physiological needs. Sometimes caregivers are very busy caring for others that they neglect their health. Shifting is a common practice among health caregivers. Morning or afternoon shifts may not have a significant influence on sleep quality. However, night shifts tend to be long and exhausting. A major and long-standing effect is how it affects the gastrointestinal tract. Loss of sleep can cause indigestion, which triggers various symptoms such as heartburn, constipation, increased level of flatulence, pain around the stomach, vomiting, and irritability. If this continues for a long time, it increases the rate of colon cancer. 

Night shift involves continuous vigilance and alertness. The benefit of sleep to the human body and mind cannot be overemphasized. Adequate sleep is important for efficiency in providing quality healthcare. Caring for patients requires alertness which sleep deprivation may negatively influence. However, studies reveal that health care providers get less than optimal sleep due to balancing their work schedule and personal life. Adequate night sleep improves cognitive reasoning, which is essential in providing care. The majority of health care providers complained of weakness after the first night shift. The result was a reduction in concentration and efficiency of care. A recent study revealed that sleep impairment results in lower ratings and quality of care.

myAir specializes in stress management, personalized nutrition bars that promote wellness. We investigate reasons for certain situations, like a reduction in work efficiency and sleep. The app makes suggestions on habits to improve sleep quality. We understand the relevance of sleep to everyone. Nevertheless, it is different for health caregivers. Inadequate sleep puts the caregivers and their patients at risk. With caregivers, the consequences of poor sleep quality are in numerous folds. myAir team is committed to promoting the well-being of their clients. We have established a relationship between the night shift and sleeping problems. Hence, we encourage clients to practice healthy sleeping and napping patterns to make up for missed sleep. The health caregivers are taking care of others. Hence, we are here to care for them!   


Shift work is any working schedule that deviates from the regular working hours of 7 am-6 pm associated with most other work. In addition, shift work is in three basic divisions; morning, afternoon, and night shift with 8 hours difference. Shift work occurs in various sectors. However, it is a norm of the health sector. Sickness has no sense of time. Therefore, healthcare requires a 24/7 availability of care providers. In some situations, the absence of a health specialist may cost a life. The caregiver may serve as the eye, ears, hands, and voice for the patient to deliver around-the-clock intervention for quick rehabilitation. Most of this extends to the night shift, which is meant for a good sleep and the time to relieve the day's stress. However, healthcare providers cannot choose to sleep at the expense of their patient’s wellbeing.

Over time, this shift work affects the normal circadian rhythm for the health workers. Let us take a few seconds to explain the circadian rhythm. It is a 24 hours body response to the sleep and wake cycle in response to physiological changes such as light or darkness, body status, and melatonin secretion. The night shift distorts the body's response to the normal sleep-wake cycle. Once this happens, they try to leverage the daytime to catch up on lost sleep. However, they may feel a level of dissatisfaction with arousal because they feel they are not well-rested. This can lead to insomnia if there is a continuous alteration to the circadian rhythm, and this we know can affect the functioning of such individuals.

Studies show that workers involved in shift work majorly experience sleep disturbance, excessive sleep time, and weakness. All of the above is a result of an inappropriate time of sleep. A good night’s sleep ensures optimal performance at work. Therefore, a deviation from the usual sleep pattern may reduce work efficiency. The use of caffeinated drinks is prevalent among shift workers to boost alertness and increase performance. 


There are numerous effects of shift work on the sleep quality of the health care workers. There will be a reduced brain output; studies have shown that the Central Nervous System (CNS) needs sleep for maximal functioning. However, sleep deprivation can result in low processing of information and feedback. When sleeping, new neurons are formed at the brain center containing information acquired during the day. Inadequate sleep makes the brain unable to create this information.

Inadequate sleep affects decision-making skills and creativity. One of the core duties of healthcare givers is making quality decisions that are beneficial to the patients. Sleep deprivation reduces the ability to make good decisions in critical situations. The consequences are bidirectional; they may affect the caregiver or the patients' life. In providing care, creativity is essential to deal with some situations. However, when the brain is exhausted, there is a reduction in critical thinking levels. Healthcare providers who work continuously work night shifts experience difficulty in maintaining concentration. Several hazards are associated with the healthcare profession. They include a risk for needle prick and infection by contact with contaminated materials. Adequate sleep keeps the mind alert to avoid occupational hazards. However, poor concentration may increase the risk of accidents. For example, suppose a sleep-deprived nurse is trying to withdraw medication from a vial. The chances that she will doze off in the process are high, putting her at risk of injury from the needle prick. Sleep is a physiologic process. Therefore, when the body does not get adequate sleep, it compensates for increasing daytime drowsiness. Daytime drowsiness reduces efficiency, puts the caregiver at risk for injury and malpractice. The care receiver is also at risk for injury, negligence, and poor quality care.  

 Recent studies show that many sleep-deprived individuals tend to think that their level of performance has increased compared to when they have a night of quality sleep. This is a typical scenario of self-denial. In reality, they make mistakes that could cost their license due to the injury or death of patients. Sleep deprivation due to shift work can also cause some imbalances in the immune system. The immune system is the army of the body; it fights infections and eradicates pathogenic organisms. However, a weak immune system predisposes the caregiver to several illnesses. Consequently, there is a reduction in the number of health caregivers available because they have assumed the sick role. 

 Sleep plays a critical role in mood stabilization. A classical sign of sleep deprivation is the development of aggressive behaviors. The health care sector is a field that requires patience and positive behavior to build therapeutic communication. When a patient observes the caregiver is aggressive, it generates fear and mistrust. Some patients may request discharge against medical advice because they do not believe they are safe in the hospital. In general, sleep deprivation affects important systems of the body, such as the CVS, Respiratory system, digestive system, endocrine system, and others. Sleep deprivation causes a sustained high level of blood pressure. An individual with high blood pressure may experience headaches and dizziness, which reduces efficiency at the workplace.


The phrase "Health is wealth" is common. The health of caregivers is important if they are to provide satisfactory services. There is a direct relationship between shift on sleep pattern and efficiency at the workplace. Studies show that caregivers who work the night shift complain of fatigue, sleep deprivation, and stress. This could negatively affect the quality of health care services they provide. The health sector is critical to the well-being of society. A defect in the wellness of caregivers may affect their wellness and efficiency. This may result in a longer recovery period for patients. The caregiver that is fatigued may lack the focus and creativity to nurse the patient to good health. Sleep deprivation may affect the mood of caregivers. It influences the relationship with patients and how they deliver care. Sometimes, the caregiver may be doing more harm than good because they lack quality sleep.

Caregivers who work the night shift may experience poor sleep quality due to disturbances to the sleep-wake pattern. An alteration to the circadian rhythm affects physical and mental health. There are at high risk for anxiety, depression, and easy irritability. The sense of safety may also diminish over subsequent night shifts with less night sleep. This may lead to lethargy and impatience in following necessary safety precautions. Inadequate night sleep can cause a nervous breakdown at work. Every individual needs a good night's sleep to function optimally the next day. In addition, persistent sleep deprivation can cause caregivers to collapse at work. In this case, the caregiver becomes a patient. Incidences like this do not foster hope in patients, especially if their caregiver collapses in front of them.

Finally, sleep deprivation may cause road traffic accidents. Health caregivers are at a high risk of road traffic accidents. The healthcare providers may fall asleep while driving, and this may become a disaster. Inadequate sleep reduces efficiency in performing tasks that require optimal attention. The result is an increase in errors in patient care. In caring for patients, mistakes could cost a life or complications that prolong hospital stay. Health caregivers who work shifts ought to get time to rest to avoid the dire consequence of sleep deprivation to their health and patients. 


Original publication: The Impact of Shift Work on Sleep, Alertness, and Performance in Healthcare Workers


By Saranea Ganesan, Michelle Magee, Julia E. Stone, Megan D. Mulhall, Allison Collins, Mark E. Howard, Steven W. Lockley, Shantha M. W. Rajaratnam & Tracey L. Sletten

Published in 2019 by Springer Nature

Footnote: No potential conflict of interest relevant to this article was reported.


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