Night shift work is associated with an increased risk of asthma

IntroductionShift work causes misalignment between internal circadian time and the external light/dark cycle and is associated with metabolic disorders and cancer. Approximately 20% of the working population in industrialised countries work permanent or rotating night shifts, exposing this large population to the risk of circadian misalignment-driven disease. Analysis of the impact of shift work on chronic inflammatory diseases is lacking. We investigated the association between shift work and asthma.MethodsWe describe the cross-sectional relationship between shift work and prevalent asthma in >280000 UK Biobank participants, making adjustments for major confounding factors (smoking history, ethnicity, socioeconomic status, physical activity, body mass index). We also investigated chronotype.ResultsCompared with day workers, ‘permanent’ night shift workers had a higher likelihood of moderate-severe asthma (OR 1.36 (95% CI 1.03 to 1.8)) and all asthma (OR 1.23 (95% CI 1.03 to 1.46)). Individuals doing any type of shift work had higher adjusted odds of wheeze/whistling in the chest. Shift workers who never or rarely worked on nights and people working permanent nights had a higher adjusted likelihood of having reduced lung function (FEV1 <80% predicted). We found an increase in the risk of moderate-severe asthma in morning chronotypes working irregular shifts, including nights (OR 1.55 (95% CI 1.06 to 2.27)).ConclusionsThe public health implications of these findings are far-reaching due to the high prevalence and co-occurrence of both asthma and shift work. Future longitudinal follow-up studies are needed to determine if modifying shift work schedules to take into account chronotype might present a public health measure to reduce the risk of developing inflammatory diseases such as asthma.

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Circadian misalignment increases mood vulnerability in simulated shift work

Scientific Reports ◽

10.1038/s41598-020-75245-9 ◽

2020 ◽

Vol 10 (1) ◽

Cited By ~ 1

Author(s):

Sarah L. Chellappa ◽

Christopher J. Morris ◽

Frank A. J. L. Scheer

Keyword(s):

Shift Work ◽

Night Shift ◽

Well Being ◽

Continuous Exposure ◽

Shift Workers ◽

Circadian Misalignment ◽

Alignment Condition ◽

Increased Risk ◽

Mood Effects ◽

Alignment Interaction

Abstract Night shift work can associate with an increased risk for depression. As night workers experience a ‘misalignment’ between their circadian system and daily sleep–wake behaviors, with negative health consequences, we investigated whether exposure to circadian misalignment underpins mood vulnerability in simulated shift work. We performed randomized within-subject crossover laboratory studies in non-shift workers and shift workers. Simulated night shifts were used to induce a misalignment between the endogenous circadian pacemaker and sleep/wake cycles (circadian misalignment), while environmental conditions and food intake were controlled. Circadian misalignment adversely impacted emotional state, such that mood and well-being levels were significantly decreased throughout 4 days of continuous exposure to circadian misalignment in non-shift workers, as compared to when they were under circadian alignment (interaction of “circadian alignment condition” vs. “day”, mood: p < 0.001; well-being: p < 0.001; adjusted p-values). Similarly, in shift workers, mood and well-being levels were significantly reduced throughout days of misalignment, as compared to circadian alignment (interaction of “circadian alignment condition” vs. “day”, mood: p = 0.002; well-being: p = 0.002; adjusted p-values). Our findings indicate that circadian misalignment is an important biological component for mood vulnerability, and that individuals who engage in shift work are susceptible to its deleterious mood effects.

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Shift work is associated with positive COVID-19 status in hospitalised patients

10.1101/2020.12.04.20244020 ◽

2020 ◽

Cited By ~ 1

Author(s):

Robert Maidstone ◽

Simon G Anderson ◽

David W Ray ◽

Martin K Rutter ◽

Hannah J Durrington ◽

...

Keyword(s):

Shift Work ◽

Healthcare Workers ◽

Night Shift ◽

Multivariate Logistic Regression ◽

Shift Workers ◽

Night Shift Work ◽

Work Factors ◽

Hospitalised Patients ◽

Disease Exposure ◽

The Impact

AbstractIntroductionShift work is associated with both mental, and physical ill health, including lung disease and infections. However, the impact of shift work on significant COVID-19 illness has not be assessed. We therefore investigated whether shift work is associated with COVID-19.Methods501,000 UK biobank participants were linked to secondary care SARS-CoV-2 PCR results from public health England. Healthcare workers and those without an occupational history were excluded from analysis.ResultsMultivariate logistic regression taking into account age, sex, ethnicity and deprivation index revealed that irregular shift work (OR 2.42 95%CI 1.92-3.05), permanent shift work (OR 2.5, 95%CI 1.95-3.19), day shift work (OR 2.01, 95%CI 1.55-2.6), irregular night shift work (OR 3.04, 95%CI 2.37-3.9) and permanent night shift work (OR 2.49, 95%CI 1.67-3.7) were all associated with positive COVID-19 tests compared to participants that did not perform shift work. This relationship persisted after adding sleep duration, chronotype, pre-morbid disease, BMI, alcohol and smoking. Work factors (proximity to a colleague combined with estimated disease exposure) were positively correlated with COVID-19 incidence (r2=0.248, p=0.02). If this was added to the model shift work frequency remained significantly associated with COVID-19. To control for non-measured occupational factors the incidence of COVID-19 in shift workers was compared to colleagues in the same job who did not do shift work. Shift workers had a higher incidence of COVID-19 (p<0.01).ConclusionsShift work is associated with a higher likelihood of in-hospital COVID-19 positivity. This risk could potentially be mitigated via additional workplace precautions or vaccination.

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Obesity and shift work: chronobiological aspects

Nutrition Research Reviews ◽

10.1017/s0954422410000016 ◽

2010 ◽

Vol 23 (1) ◽

pp. 155-168 ◽

Cited By ~ 230

Author(s):

L. C. Antunes ◽

R. Levandovski ◽

G. Dantas ◽

W. Caumo ◽

M. P. Hidalgo

Keyword(s):

Shift Work ◽

Biological Clock ◽

Overweight And Obesity ◽

Present Review ◽

Epidemiological Evidence ◽

Shift Workers ◽

Circadian Misalignment ◽

Increased Risk ◽

Business Competitiveness ◽

The Impact

The present review has the objective of summarising chronobiological aspects of shift work and obesity. There was a systematic search in PubMed databases, using the following descriptors: shift work; obesity; biological clock. Shift work is extremely frequent in several services and industries, in order to systematise the needs for flexibility of the workforce, necessary to optimise productivity and business competitiveness. In developing countries, this population represents a considerable contingent workforce. Recently, studies showed that overweight and obesity are more prevalent in shift workers than day workers. In addition, the literature shows that shift workers seem to gain weight more often than those workers submitted to a usual work day. In conclusion, there is considerable epidemiological evidence that shift work is associated with increased risk for obesity, diabetes and CVD, perhaps as a result of physiological maladaptation to chronically sleeping and eating at abnormal circadian times. The impact of shift work on metabolism supports a possible pathway to the development of obesity and its co-morbities. The present review demonstrated the adverse cardiometabolic implications of circadian misalignment, as occurs chronically with shift workers.

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Night Shift Among Women: Is It Associated With Difficulty Conceiving a First Birth?

Frontiers in Public Health ◽

10.3389/fpubh.2020.595943 ◽

2020 ◽

Vol 8 ◽

Author(s):

Renae C. Fernandez ◽

Vivienne M. Moore ◽

Jennifer L. Marino ◽

Melissa J. Whitrow ◽

Michael J. Davies

Keyword(s):

Shift Work ◽

Night Shift ◽

Fertility Treatment ◽

Menstrual Irregularity ◽

Female Reproduction ◽

First Birth ◽

Shift Workers ◽

Night Shift Work ◽

Paid Employment ◽

Increased Risk

Background: Asynchrony in circadian processes alters many physiological systems, including female reproduction. Thus, there are possible reproductive consequences of night shift work for women including menstrual irregularity, endometriosis, and prolonged time to conception. This study examined whether women who worked night shift were more likely than those who did not to require fertility treatment to conceive a first birth, whether they had specific infertility diagnoses, and if such relationships were age-specific.Methods: In a retrospective data linkage study of 128,852 primiparous women, fertility treatment data were linked to the state perinatal registry for South Australia (1986–2002). Potential exposure to night shift work was assessed using a job-exposure matrix. First, the association between night shift work and fertility treatment was assessed among (1) all women, then (2) women in paid employment, using logistic regression. Interactions between age and shift work status were also examined. Secondly, among women who conceived with fertility treatment, we assessed associations between night shift work and type of infertility diagnosis. Potential confounders were considered in all analyses.Results: Among women ≤35 years, night shift workers were more likely to require fertility treatment (all: OR = 1.40, 95% CI 1.19–1.64; in paid employment: OR = 1.27, 95% CI 1.08–1.50). There were no associations among women >35 years. Ethnicity, socioeconomic status and smoking did not affect these results. Among women who underwent fertility treatment, night shift workers were more likely than day workers to have menstrual irregularity (OR = 1.42, 95% CI 1.05–1.91) or endometriosis (OR = 1.34, 95% CI 1.00–1.80).Conclusions: Night shift work may contribute to increased need for fertility treatment in younger women. This increased risk may reflect young women's vulnerability in terms of poor tolerance of night shift work, and/or lack of control and choice about shift schedule.

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High risk of near-crash driving events following night-shift work

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1510383112 ◽

2015 ◽

Vol 113 (1) ◽

pp. 176-181 ◽

Cited By ~ 76

Author(s):

Michael L. Lee ◽

Mark E. Howard ◽

William J. Horrey ◽

Yulan Liang ◽

Clare Anderson ◽

...

Keyword(s):

High Risk ◽

Shift Work ◽

Occupational Safety ◽

Motor Vehicle ◽

Night Shift ◽

Driving Performance ◽

Previous Night ◽

Shift Workers ◽

Night Shift Work ◽

The Impact

Night-shift workers are at high risk of drowsiness-related motor vehicle crashes as a result of circadian disruption and sleep restriction. However, the impact of actual night-shift work on measures of drowsiness and driving performance while operating a real motor vehicle remains unknown. Sixteen night-shift workers completed two 2-h daytime driving sessions on a closed driving track at the Liberty Mutual Research Institute for Safety: (i) a postsleep baseline driving session after an average of 7.6 ± 2.4 h sleep the previous night with no night-shift work, and (ii) a postnight-shift driving session following night-shift work. Physiological measures of drowsiness were collected, including infrared reflectance oculography, electroencephalography, and electrooculography. Driving performance measures included lane excursions, near-crash events, and drives terminated because of failure to maintain control of the vehicle. Eleven near-crashes occurred in 6 of 16 postnight-shift drives (37.5%), and 7 of 16 postnight-shift drives (43.8%) were terminated early for safety reasons, compared with zero near-crashes or early drive terminations during 16 postsleep drives (Fishers exact:P= 0.0088 andP= 0.0034, respectively). Participants had a significantly higher rate of lane excursions, average Johns Drowsiness Scale, blink duration, and number of slow eye movements during postnight-shift drives compared with postsleep drives (3.09/min vs. 1.49/min; 1.71 vs. 0.97; 125 ms vs. 100 ms; 35.8 vs. 19.1; respectively,P< 0.05 for all). Night-shift work increases driver drowsiness, degrading driving performance and increasing the risk of near-crash drive events. With more than 9.5 million Americans working overnight or rotating shifts and one-third of United States commutes exceeding 30 min, these results have implications for traffic and occupational safety.

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The Impact of Shift Work on Diabetes Self-Management Activities

Journal of Doctoral Nursing Practice ◽

10.1891/2380-9418.12.1.66 ◽

2019 ◽

Vol 12 (1) ◽

pp. 66-72

Author(s):

Daniel J. Navarro ◽

Patricia T. Alpert ◽

Chad Cross

Keyword(s):

Physical Activity ◽

Primary Care ◽

Blood Glucose ◽

Shift Work ◽

Diabetes Care ◽

Night Shift ◽

Blood Glucose Control ◽

Self Management ◽

Shift Workers ◽

The Impact

BackgroundOnce a person is diagnosed with diabetes, aggressive management is imperative to minimize poor glycemic control devastating outcomes. However, for some patients reaching optimum blood glucose levels is challenging due to the complexity of diabetes care. To achieve good blood glucose control, patients affected by diabetes must engage in self-care activities that include routine blood glucose check, dietary control, physical activity, medication regimen, and routine medical provider visits. Diabetes-associated self-care activities aimed to reach good blood glucose control can be hindered by multiple factors including shift work.ObjectiveTo evaluate self-management activities of individuals affected by diabetes who are employed as shift workers. This study also informs primary care nurse practitioners of the challenges shift workers face in managing their disease.MethodsThis was a cross-sectional descriptive study. Participants were individuals affected by type II diabetes from a single primary care practice (N = 86); 45 were individuals working on the dayshift and 41 worked on the evening/night shift. Each participant completed the diabetes self-management questionnaire and author-developed demographic/supplemental questionnaire.ConclusionsThere were no differences in self-reported diabetes management activities (i.e., physical activity, glucose management, and healthcare use) between the two groups. Thirty-nine percent of participants working shifts reported worse sleep patterns compared to their dayshift counterparts (X2[1, N = 85] = 8.73, p = .003). Evening/night shift workers also reported more symptoms such as leg pain, fungal infection, numbness of the feet and legs, dizziness, and vision changes (X2[1, N = 79] = 43.037, p < .001).Implications for PracticeA better understanding of the impact that shift work has on diabetes care may help healthcare providers formulate meaningful treatment plans to meet the needs of evening/night shift diabetic workers. The use of a patient-centered medical home is one strategy.

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Social jetlag and sleep debts are altered in different rosters of night shift work

PLoS ONE ◽

10.1371/journal.pone.0262049 ◽

2022 ◽

Vol 17 (1) ◽

pp. e0262049

Author(s):

Swaantje Casjens ◽

Frank Brenscheidt ◽

Anita Tisch ◽

Beate Beermann ◽

Thomas Brüning ◽

...

Keyword(s):

Sleep Quality ◽

Sleep Deprivation ◽

Sleep Duration ◽

Shift Work ◽

Night Shift ◽

Shift Workers ◽

Social Jetlag ◽

Sleep Debt ◽

The Impact ◽

Night Shifts

Background Night and shift work are suspected to cause various adverse effects on health and sleep. Sleep deprivation through shift work is assumed to be compensated on free days. So far it is not clear how different shift systems and shift lengths affect sleep structure on work and free days. Especially working night shifts disrupts the circadian rhythm but also extended working hours (12h) might affect sleep characteristics. Hitherto, the magnitude of sleep debt, social jetlag, and Locomotor Inactivity During Sleep (LIDS) in different shift systems is unknown. Methods Here, we investigated the impact of five different shift rosters on sleep in 129 industrial workers from Germany. Permanent night work with multiple shift systems with and without night shifts and with different shift lengths were compared. Wrist-activity was monitored over 28 days revealing sleep on- and offsets as well as LIDS as proxy for sleep quality. Overall, 3,865 sleep bouts comprising 22,310 hours of sleep were examined. Results The mean daily age-adjusted sleep duration (including naps) was 6:43h and did not differ between shift workers of different rosters. However, sleep duration on workdays was particularly low in rotational shift systems with 12h-shifts (5:00h), while overall sleep debt was highest. Shift workers showed a median absolute social jetlag of 3:03h, which differed considerably between shift types and rosters (p<0.0001). Permanent night workers had the highest social jetlag (5:08h) and latest mid-sleeps on workdays and free days. Sleep quality was reduced in permanent night shift workers compared with shift workers in other rosters and differed between daytime and nighttime sleep. Conclusions Shift work leads to partial sleep deprivation, which particularly affects workers in 12h-shifts and permanent night shifts. Working these shifts resulted in higher sleep debts and larger absolute social jetlag whereas sleep quality was especially reduced in permanent night shift workers compared with shift workers of other rosters.

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Shift Work and Work-Family Conflict: A Systematic Review

sozialpolitik ch ◽

10.18753/2297-8224-165 ◽

2020 ◽

Vol 2020 (3) ◽

Author(s):

Anne Marit Wöhrmann ◽

Grit Müller ◽

Kathrin Ewert

Keyword(s):

Shift Work ◽

Family Conflict ◽

Social Life ◽

Night Shift ◽

Inclusion Criteria ◽

Work Family Conflict ◽

Shift Workers ◽

State Of Research ◽

Work Family ◽

The Impact

Shift work occupies precious time for family and social life. The aim of this review was to systematically assess the state of research on the impact of shift work on work-fam-ily conflict. A systematic literature search was conducted in PubMed and EBSCO to identify studies published between 1990 and 2017. In the end, 36 articles met the inclusion criteria and were considered in this review. Shift workers show higher levels of work-family conflict in comparison to workers in regular day schedules. Different shift types and a large variation of shift characteristics have been studied. Results point to a higher work-family conflict especially among night shift workers and those working in a shift schedule, including weekend work. Research testing for causality is missing.

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P040 Night Shift Work and Disease: A Systematic Review of the Role of Oxidative Stress

SLEEP Advances ◽

10.1093/sleepadvances/zpab014.088 ◽

2021 ◽

Vol 2 (Supplement_1) ◽

pp. A34-A34

Author(s):

M Gibson

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Shift Work ◽

Night Shift ◽

Reactive Oxygen ◽

Oxygen Species ◽

Repair Capacity ◽

Shift Workers ◽

Night Shift Work ◽

The Impact

Abstract Night shift workers make up an essential part of the modern workforce. However, night shift workers have higher incidences of late in life diseases and earlier mortality. Night shift workers are exposed to constant light and experience circadian rhythm disruption. Sleep disruption is thought to increase oxidative stress, defined as an imbalance of excess pro-oxidative factors and reactive oxygen species over anti-oxidative activity. Oxidative stress can damage cells, proteins and DNA and can eventually lead to varied chronic diseases such as cancer, diabetes, cardiovascular disease, Alzheimer’s and dementia. This review aimed to understand whether night shift workers were at greater risk of oxidative stress and to contribute to a consensus on this relationship. Twelve studies published in 2001–2019 examining 2,081 workers were included in the review. Studies compared both the impact of working a single shift and in comparisons between those who regularly work night shifts and only day shifts. All studies had evidence to support this relationship across a range of oxidative stress indicators, including: increased DNA damage, reduced DNA repair capacity, increased lipid peroxidation, higher levels of reactive oxygen species, and to a lesser extent, a reduction in antioxidant defence. This research supports the theory that melatonin and the sleep wake cycle mediate the relationship between shift work and oxidative stress. It is concluded that night shift work increases the risk for oxidative stress and therefore future disease. Recommendations are made to promote the long-term health of shift workers considering these findings.

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Working the Night Shift: The Impact of Compensating Wages and Local Economic Conditions on Shift Choice

Economics Research International ◽

10.1155/2014/632506 ◽

2014 ◽

Vol 2014 ◽

pp. 1-15 ◽

Cited By ~ 1

Author(s):

Colene Trent ◽

Walter J. Mayer

Keyword(s):

Regression Model ◽

Shift Work ◽

Night Shift ◽

Economic Conditions ◽

Compensating Differentials ◽

Switching Regression ◽

Shift Workers ◽

Night Shift Work ◽

The Impact ◽

Night Shifts

The theory of compensating differentials asserts that night shift workers should receive compensating wage differentials due to undesirable work conditions. In weak local economies, workers may have difficulty finding jobs; thus, these workers might be more likely to accept night shift work and be less concerned with the size of the compensating differential for night shifts. Using CPS data from 2001, this paper employs maximum likelihood estimation of an endogenous switching regression model to analyze wages of day and night shift workers and shift choice. The findings indicate the presence of selection bias, thus emphasizing the importance of correcting for self-selection into night shifts. The average of the estimated wage differentials for night shift work is negative for the overall sample, with differentials varying by worker characteristics. The shift differential is found to be a statistically significant predictor of shift choice, indicating that shift premiums play an important role in motivating individuals to select night shift work. Using two measures of local economic conditions and a new method of analyzing interaction effects in the context of an endogenous switching regression model, this paper finds limited evidence that weak local economic conditions lessen the impact of compensating differentials on shift choice.

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