Dietary Patterns under the Influence of Rotational Shift Work Schedules: A Systematic Review and Meta-Analysis.

Workers employed in rotating shift schedules are at a higher metabolic risk compared with those in regular day and fixed shift schedules; however, the contribution of diet is unclear. This systematic review aimed to investigate how rotating shift work schedules affect dietary energy intake and dietary patterns compared with regular day and fixed shift schedules. In addition, intraperson energy intake and dietary pattern comparisons within rotating shift schedules were investigated. Database searches were conducted on MEDLINE, Cochrane, CINAHL, PSYCinfo, EMBASE, and Scopus, in addition to manual search of bibliographic references, to identify articles. Two separate meta-analyses compared dietary intake between day work and rotating shift work schedules and within the rotational shift work group (morning/day and night shifts). Differences in dietary patterns were synthesized narratively. Thirty-one studies (n = 18,196 participants) were included in the review, and meta-analyses were conducted with 24-hour mean energy intake data from 18 (n = 16,633 participants) and 7 (n = 327 participants) studies, respectively. The average 24-hour energy intake of rotating shift workers was significantly higher than that of workers in regular daytime schedules [weighted mean difference (WMD): 264 kJ; 95% confidence interval (CI): 70, 458 kJ; P < 0.008; I2 = 63%]. However, the mean difference in 24-hour energy intake between morning/day shifts compared with night shifts within rotational shift schedules was not statistically significant (WMD: 101 kJ; 95% CI: -651, 852 kJ; P = 0.79; I2 = 77%). Dietary patterns of rotating shift workers were different from those of day workers, showing irregular and more frequent meals, increased snacking/eating at night, consumption of fewer core foods, and more discretionary foods. This review highlights that dietary intake in rotational shift workers is potentially higher in calories and features different eating patterns as a consequence of rotating shift work schedules. This review was registered at PROSPERO as ID 182507.

Association between Shift Work Schedules and Cardiovascular Events in a Multi-Ethnic Cohort.

BACKGROUND: Shift work is known to increase the risk of cardiometabolic diseases and mortality. We investigate the relationship between shift work schedules and cardiometabolic risk factors (smoking, hypertension, and obesity) and their association with cardiometabolic diseases (diabetes and cardiovascular diseases) in a multi-ethnic population from Singapore. METHODS: 2469 participants from the Singapore-based Multi-Ethnic Cohort underwent physical and clinical assessments. Shift work schedules (morning, evening, night, and mixed) were assessed using a validated questionnaire. RESULTS: Among shift workers, night shift workers had a significantly higher prevalence of smoking (54.5%), diabetes (27.3%), and cardiovascular events (14.1%). Compared to non-shift workers, workers in the night (OR = 2.10, 95%CI: 1.26-3.41) and mixed (OR = 1.74, 95%CI: 1.22-2.48) shift groups were more likely to be current smokers. A significant association between shift duration and smoking (OR = 1.02, 95%CI: 1.00-1.03) was also observed, with longer shift duration (in years) leading to an increase in smoking behavior. No significant associations were found between shift work schedules and hypertension, obesity (BMI), diabetes, and cardiovascular disease, as well as other cardiometabolic risk factors and diseases. CONCLUSION: This study found that shift schedules and shift duration were most strongly associated with smoking status after covariate adjustments (age, gender, ethnicity, socioeconomic status, and work arrangement), with night and mixed shift types being strongly associated with current smoker status. As smoking is a modifiable risk factor for cardiometabolic disease, employers of shift workers should increase work-based health interventions to control smoking and promote a healthier workforce.

Rotating Night Shift Work and Bladder Cancer Risk in Women: Results of Two Prospective Cohort Studies.

Bladder cancer is the sixth most common cancer in the United States. Night shift work has previously been linked with cancer risk. Whether there is an association between rotating night shift work and bladder cancer in women has not been studied previously. Eligible participants in the Nurses' Health Study (NHS, n = 82,147, 1988-2016) and Nurses' Health Study II (NHSII, n = 113,630, 1989-2015) were prospectively followed and a total of 620 and 122 incident bladder cancer cases were documented during the follow-up of NHS and NHSII, respectively. Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (95% CI) for bladder cancer incidence. We observed a significantly increased risk of bladder cancer among women with >5 years of night shift work history compared with women who never worked rotating night shifts in NHS (HR = 1.24; 95%CI = 1.01-1.54, p for trend = 0.06), but not in the pooled NHS and NHS II (HR = 1.18; 95%CI = 0.97-1.43, p for trend = 0.08). Secondary analyses stratified by smoking status showed no significant interaction (p = 0.89) between the duration of rotating night shift work and smoking status. In conclusion, our results did not provide strong evidence for an association between rotating night shift work and bladder cancer risk.

The association between shift work and the incidence of reflux esophagitis in Korea: a cohort study.

Shift work has adverse health effects such as diabetes, cardiovascular disease, sleep disturbance, depression, and breast cancer. Gastro-esophageal reflux disease (GERD) results in lesions such as reflux esophagitis (RE) and Barrett's esophagus. This study investigated the association between shift work and RE. A cohort study was conducted with 140,553 participants who were followed up at least once from 2012 to 2018. Type of working and shift types were collected using standardized questionnaires. Esophagogastroduodenoscopy (EGD) was performed by experienced endoscopists who were blinded to the aims of this study. According to the Los Angeles classification, RE was categorized based on the extent of esophageal mucosal breaks. During the 469,217.2 person-years of follow-up, 35,185 participants developed incident cases of RE. The multivariable adjusted hazard ratio (95% confidence intervals) for incident cases comparing shift work to fixed day work was 1.09 (1.04-1.13). This association was more strongly observed in the younger age group (18-39 years old) and the female group. In conclusion, shift work was significantly associated with the incidence of RE. Particularly, the results were more significant in the younger and female groups.

Shift work schedule and sleep patterns in relation to incident depression: Evidence from a prospective cohort study.

This study aims to explore the joint associations of shift work and sleep patterns with incident depression. The present prospective cohort using data from UK biobank, included 220,651 participants aged 38 to 71 years recruited between 2006 and 2010. Every participant finished a self-completed touch-screen questionnaire. Hazards ratios (HRs) with corresponding 95% confidence intervals (CIs) of incident depression were reported for shift work and sleep patterns by Cox-proportional hazard models. The average follow-up time was 12.13±1.94 years and the incidence rate of depression was 2.95 (2.89-3.02) per 1000 person-years. After fully adjustment, the participants with irregular and permanent night shifts companied by any sleep pattern were significantly associated with increased risk of incident depression compared with no shift work companied by favorable sleep patterns. The females seemed to be more vulnerable when having night shifts and unfavorable sleep patterns compared with the males. The increased risk of incident depression associated with shift work regardless of night shifts and evening/weekend shifts was not able to offset by favorable sleep patterns. The workers with unhealthy sleep patterns, especially inappropriate sleep duration and insomnia companied by shift work schedule should be paid more attention considering higher risk of depression.

Negative representations of night-shift work and mental health of public hospital healthcare workers in the COVID-19 era (Aladdin survey).

BACKGROUND: Many risk factors impact the health of hospital night workers, which can lead to physical and mental health disorders. During the recent period, night hospital workers have been particularly stressed. This study therefore aims to: (i) To document the prevalence of depression, anxiety, sleep disorders, and symptoms suggestive of post-traumatic stress disorder in night shift workers (NSHW) working in Parisian public hospitals after France's first COVID-19 wave ended; (ii) To estimate the effect of negative representations and perceptions of night shift work on these mental health outcomes. METHODS: An observational cross-sectional online survey of NSHW (June to September 2020) in 39 public hospitals in Paris, France. Standard scales were used to measure mental health outcomes. Weighted multinomial logistic regression models supported the identification of predictors of depression (score > 10 on the Hospital Anxiety and Depression Scale, HADS, for depression), anxiety (score > 10 on the HADS for anxiety), severe insomnia (score > 21 on the Insomnia Severity Index, ISI) and symptoms suggestive of post-traumatic stress disorder (score > 36 on the Impact of Event Scale-Revised, IES-R). RESULTS: The weighted prevalence rates [95% confidence interval] of depression, anxiety, severe insomnia, and symptoms of post-traumatic stress disorder were, respectively, 18.9% [16.5-21.2], 7.6% [6.0-9.1], 8.6% [6.9-10.2] and 11.7% [9.7-13.6]. After multiple adjustment, organizational changes in NSHW professional lives due to the COVID-19 pandemic (such as moving to another hospital department and modified schedules) and NSHW-perceived negative representations of night work were significantly associated with all studied mental health outcomes. CONCLUSION: Our findings confirm the importance of monitoring mental health and sleep quality among NSHW in Parisian public hospitals, even more during health crises. Multilevel interventions aiming at reducing negative representations and improving work organization are urgently needed to improve overall health of this frontline healthcare providers group.

Shift Work and Sleep Disturbance in the Oil Industry.

BACKGROUND: Rotating shift work is common in high-hazard industries, despite documented associations with sleep disturbance and impairment. In the oil industry, where rotating and extended shift schedules are used to staff safety-sensitive positions, work intensification and increasing overtime rates have been broadly documented over the last few decades. Research on the impacts of these work schedules on sleep and health has been limited for this workforce. METHODS: We examined sleep duration and quality among rotating shift workers in the oil industry and explored associations between schedule characteristics, sleep, and health outcomes. We recruited hourly refinery workers from the West and Gulf Coast oil sector members of the United Steelworkers union. FINDINGS: Impaired sleep quality and short sleep durations were common and associated with health and mental health outcomes common among shift workers. Shortest sleep durations followed shift rotations. Early rise and start times were associated with shorter sleep duration and poorer sleep quality. Drowsiness and fatigue-related incidents were common. CONCLUSION/APPLICATION TO PRACTICE: We observed lower sleep duration and quality and increased overtime in 12-hour rotating shift schedules. These long workdays with early start times may reduce available hours for quality sleep; here they were associated with reduced exercise and leisure activity which correlated with good sleep. This safety-sensitive population appears severely impacted by poor sleep quality, which has broader implications for process safety management. Later start times, slower rotation, and a reconsideration of two-shift schedules are interventions to consider for improving sleep quality among rotating shift workers.

Shift Work and Mental Health Among Radiologic Technologists.

PURPOSE: To determine the relationships between mental health (depression and anxiety) and engaging in shift work, working weekend shifts, and taking call for radiologic technologists, and to identify coping strategies used to manage depression and anxiety. METHODS: Validated instruments were used to measure depression and anxiety levels among a sample of radiologic technologists who were members of Advanced Health Education Center. The participants also identified their primary work shift and their frequency of working weekends and taking call. RESULTS: There were 173 completed survey responses for this study. Most radiologic technologists in this study experienced mild symptoms of depression (62, 35.8%) and anxiety (57, 32.9%). Nearly half of the participants indicated that their depression and anxiety made it difficult for them to perform their jobs effectively, and about one-third of the participants believed those symptoms were intensified by shift work. A strong, positive relationship was identified between participants' total depression and anxiety scores (P < .001). There were no significant differences between shift work and total depression score (P = .06) or total anxiety score (P = .28). A significant association was found between the frequency of working weekend shifts and depression levels (P < .001) with a moderate effect size. Most of the participants identified support from family or friends, prayer and spiritual activities, and prescribed medication as common coping strategies. DISCUSSION: Findings revealed that the radiologic technologists in this study did not rely heavily on employer-based resources, such as employee assistance programs, to cope with their depression and anxiety symptoms. One speculation for underuse of these employer-based resources might be fear of being stigmatized by management or personal perceived stigma against asking for help. There is an opportunity for increased awareness of available mental health resources and acceptance of mental health management to erase the common, negative stigma associated with seeking out professional resources. CONCLUSION: Radiologic technologists in this study experienced depression and anxiety symptoms that affected their work performance and correlated with working weekend shifts; however, there was no significant relationship between shift work and depression or anxiety in this sample of radiologic technologists.

Association of Low Back Pain with Shift Work: A Meta-Analysis.

Shift work (SW) is the main working schedule worldwide, and it may cause sleep disorders, breast cancer, and cardiovascular disease. Low back pain (LBP) is a common problem in the workplace; however, the association between LBP and SW remains unclear. Therefore, we conducted a meta-analysis to determine the association between SW and LBP. This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The PubMed, Embase, and Web of Science databases using a set of associated keywords were queried. The inclusion criteria were as follows: (1) adult employees hired by a company or organization; (2) SW exposure; and (3) the outcome of LBP according to examination or assessment. A total of 40 studies were included that met the inclusion criteria for the meta-analysis. SW was significantly associated with LBP (odds ratio [OR]: 1.31, 95% confidence interval [CI]: 1.18−1.47, p < 0.00001). Furthermore, it was observed that LBP was significantly associated with night shift (NS) (OR: 1.49, 95% CI: 1.24−1.82, p < 0.0001) but not with rotating shift (RS) (OR: 0.96, 95% CI: 0.76−1.22, p = 0.49). Moreover, LBP was significantly associated with SW in health care workers (HCWs) (OR: 1.40, 95% CI: 1.20−1.63, p < 0.0001) but not in non-HCWs (OR: 1.19, 95% CI: 0.94−1.50, p = 0.14). SW was significantly associated with LBP. Furthermore, the subgroup analysis showed that NS, but not RS, was associated with LBP. Compared with SW in non-HCWs, SW in HCWs was significantly associated with LBP.

Shift work disorder, mental health and burnout among nurses: A cross-sectional study.

AIM: The aim of the study was to examine the relationships among nurses' shift work disorder, mental health and burnout to inform efforts to alleviate shift work disorder. DESIGN: This cross-sectional study was conducted in China using a web-based platform for questionnaire. METHODS: The study was comprised of a convenience sample of 1,268 Registered Nurses from 21 public hospitals in mainland China from June 2019-July 2019. Participants completed a web-based survey designed to collect demographic and other self-reported data. An independent sample t test and Pearson correlation were performed to analyse the relationship between shift work disorder, mental health and burnout. RESULTS: The vast majority (98.2%) of the participants were women between the ages of 20-59 years. The participants exhibited a higher incidence of mental health problems (58.1%) and burnout (65.5%) and those with shift work disorder exhibited a higher risk of mental health problems and burnout than those who did not have shift work disorder. Our research demonstrated that shift work disorder, combined with other variables, accounted for 40.5% of the variance in mental health (R2  = .405, adjusted R2  = .401, F = 107.214, p < .001) and 36.5% in burnout (R2  = .365, adjusted R2  = .361, F = 90.323, p < .001). Moreover, burnout negatively regulated the relationship between shift work disorder and mental health. CONCLUSION: High-risk nurses with shift work disorder were at a much higher risk of mental health problems and burnout.

Principais fatores que alteram a qualidade do sono e as consequências na vida de enfermeiros que atuam na unidade de terapia intensiva / Main factors that change the quality of sleep and the consequences in the lives of nurses who work in the intensive care unit / Principales factores que modifican la calidad del sueño y las consecuencias en la vida de los enfermeros que actúan en la unidad de cuidados intensivos

Objetivo: Analisar as evidências científicas dos principais fatores que alteram a qualidade do sono e as consequências na vida de enfermeiros que atuam na unidade de terapia intensiva. Método: Revisão integrativa da literatura, realizado de dezembro de 2021 à maio de 2022. A busca efetuou-se, através da Plataforma BVS, SciELO e CAPES utilizando os descritores: sono, "trabalho em turnos", enfermagem e "unidades de terapia intensiva", combinados ao operador booleano "AND". Resultados: Existe uma relação muito próxima entre a exposição diária a fatores estressores relacionados ao ambiente desgastante e cansativo que é a UTI, a qualidade do sono dos enfermeiros que trabalham em turnos e as consequências na vida destes. Uma vez que o padrão do ciclo do sonovigília é alterado toda qualidade do sono sofre alterações irreparáveis influenciando diretamente com a qualidade de vida social e familiar trazendo prejuízo a saúde do trabalhador. Conclusão: Sendo assim um indicativo que os danos causados pela alteração do ciclo sono-vigília tanto são prejudicial à saúde psico-social do enfermeiro como a qualidade da assistência prestada por esse trabalhador aos pacientes que estão aos seus cuidados.

Objective: To analyze the scientific evidence of principais factors that alter the quality of sleep and the consequences in the lives of nurses working in the intensive care unit. Method: Integrative literature review, conducted from December 2021 to May 2022. The search was carried out, through the VHL, SciELO and CAPES Platform using the descriptors: sleep, "shift work", nursing and "intensive care units", combined with the Boolean operator "AND". Results: There is a very close relationship between daily exposure to stressors related to the exhausting and tiring environment that is the ICU, the quality of sleep of nurses working shifts and the consequences in their lives. Since the sleep-wake cycle pattern is altered all sleep quality undergoes irreparable changes directly influencing the social and family quality of life, harming the worker's health. Conclusion: Thus, it is indicative that the damage caused by the change in the sleep-wake cycle is both harmful to the psycho-social health of nurses and the quality of care provided by this worker to patients who are in their care.

Objetivo: Analizar la evidencia científica de los factores de principais que alteran la calidad del sueño y las consecuencias en la vida de las enfermeras que trabajan en la unidad de cuidados intensivos. Método: Revisión integradora de la literatura, realizada desde diciembre de 2021 hasta mayo de 2022. La búsqueda se realizó, a través de la Plataforma BVS, SciELO y CAPES utilizando los descriptores: sueño, "trabajo por turnos", enfermería y "unidades de cuidados intensivos", combinados con el operador booleano "AND". Resultados: Existe una relación muy estrecha entre la exposición diaria a factores estresantes relacionados con el ambiente agotador y agotador que es la UCI, la calidad del sueño de las enfermeras que trabajan por turnos y las consecuencias en sus vidas. Dado que el patrón del ciclo sueño-vigilia se altera, toda la calidad del sueño sufre cambios irreparables que influyen directamente en la calidad de vida social y familiar, perjudicando la salud del trabajador. Conclusión: Por lo tanto, es indicativo de que el daño causado por el cambio en el ciclo sueño-vigilia es perjudicial tanto para la salud psicosocial de las enfermeras como para la calidad de la atención prestada por este trabajador a los pacientes que están a su cargo.

Shift work organization on nurse injuries: A scoping review.

BACKGROUND: Extended work hours and shift work can result in mistimed sleep, excessive sleepiness, and fatigue, which affects concentration and cognition. Impaired concentration and cognition negatively affect employee safety. OBJECTIVE: To examine the evidence of the impact of shift work organization, specifically work hours and scheduling, on nurse injuries including needlestick and sharps injuries, drowsy driving and motor vehicle crashes, and work-related accidents causing a near miss or actual injury to the nurse. METHODS: A scoping review was conducted using search results from five bibliographic databases. RESULTS: Through database searching, 7788 articles were identified. During the title and abstract screening, 5475 articles were excluded. Full text screening eliminated 1971 articles. During the data extraction phase, 206 articles were excluded leaving 34 articles from 14 countries in the scoping review. The results of the review suggest a strong association in nurses between long work hours and overtime and an increased risk for needlestick and sharps injuries, drowsy driving and motor vehicle crashes, and other work-related accidents. Rotating shifts increase the risk for needlestick and sharps injuries and other work-related accidents while night and rotating shifts increase the risk for drowsy driving and motor vehicle crashes. CONCLUSIONS: Proper management of work hours and scheduling is essential to maximize recovery time and reduce or prevent nurse injuries. Nurse leaders, administrators, and managers, have a responsibility to create a culture of safety. This begins with safe scheduling practices, closely monitoring for near miss and actual nurse injuries, and implementing evidence-based practice strategies to reduce these occurrences.

Physical and psychological health in intern paramedics commencing shift work: Protocol for an exploratory longitudinal study.

BACKGROUND: Paramedics are routinely exposed to shift work. Existing research shows that shift work exposure is associated with adverse mental and physical health outcomes. However, the current understanding of the impact of commencing shift work in a paramedic role on health is limited. This can be addressed by recruiting new paramedics before they commence shift work, and conducting regular follow-ups of potential biological, psychological and social changes. The present study aimed to examine changes in biological, psychological and social factors relative to pre-shift work baseline in a cohort of paramedics commencing intern employment with an Australian ambulance service. METHOD AND ANALYSIS: This observational, mixed-methods, longitudinal study aims to recruit 40 interns from one Australian ambulance service. Data collection will occur at baseline (standard day schedule for initial training), and subsequently at three months, six months, nine months and twelve months, to measure biological, psychological and social changes relative to baseline measurements. Changes in cardiometabolic markers (cholesterol, triglycerides, fasting glucose), microbiome (self-collected stool samples), sleep and physical activity (actigraphy) will be measured. Interns will also complete a battery of self-report questionnaires, sleep diaries and qualitative interviews to explore various psychological and social variables over time. Statistical analyses will be conducted using mixed effects regression, specifying a random effect of subject on the intercept, allowing participants to vary according to individual baseline levels, as well as tracking progress over time, appropriately accounting for serial correlation. Qualitative study components will be analysed via coding and thematic analysis procedures. DISCUSSION: The present study protocol is a comprehensive outline of the observational study planned. The study will allow for greater knowledge of any changes in biological, psychological and social factors during a 12-month transition to shift work. The findings from the proposed study will have implications for the development of strategies to support early-career shift workers.

Impacto de los turnos de trabajo en la calidad del sueño del personal de enfermería en dos hospitales de tercer nivel de Canarias / Impact of shift work on the sleep quality of nursing staff attending two tertiary hospitals in the Canary Island

Fundamentos: Se sabe que las características de la actividad laboral influyen en la calidad del sueño de los trabajadores. Un elemento de la actividad laboral es la turnicidad. El objetivo de este estudio fue analizar la calidad del sueño del personal de enfermería de dos hospitales de tercer nivel en Canarias y su correlación con el turno de trabajo. Métodos: Estudio observacional, analítico y transversal, de una muestra no aleatoria de 275 enfermeros y técnicos en cuidados auxiliares de enfermería (TCAEs). Se midió calidad de sueño mediante el test de Pittsburgh Sleep Quality Index (PSQI) y características sociodemográficas y laborales con un cuestionario creado ad hoc. Resultados: El 65,8% del personal de enfermería tiene una mala calidad del sueño. Se observó que la turnicidad laboral afecta a la calidad del sueño. Los trabajadores con turno antiestrés (D/N) tienen mejor calidad de sueño (M=7,31; ±DE=4,0) comparado con el turno rotatorio (M/T/N) (M= 9,06; ± DE=4,3); p=0,01. Conclusiones: Las alteraciones del sueño son frecuentes entre el personal de enfermería, siendo el turno antiestrés (D/N) el que menos afecta a la calidad del sueño (AU)

Association of shift work with incident dementia: a community-based cohort study.

BACKGROUND: Some observational studies had found that shift work would increase risks of metabolic disorders, cancers, and cardiovascular diseases, but there was no homogeneous evidence of such an association between shift work and incident dementia. This study aimed to investigate whether shift work would increase the risk of dementia in a general population. METHODS: One hundred seventy thousand seven hundred twenty-two employed participants without cognitive impairment or dementia at baseline recruited between 2006 and 2010 were selected from the UK Biobank cohort study. Follow-up occurred through June 2021. Shift work status at baseline was self-reported by participants and they were categorized as non-shift workers or shift workers. Among shift workers, participants were further categorized as night shift workers or shift but non-night shift workers. The primary outcome was all-cause dementia in a time-to-event analysis, and the secondary outcomes were subtypes of dementia, including Alzheimer's disease, vascular dementia, and other types of dementia. RESULTS: In total, 716 dementia cases were observed among 170,722 participants over a median follow-up period of 12.4 years. Shift workers had an increased risk of all-cause dementia as compared with non-shift workers after multivariable adjustment (hazard ratio [HR], 1.30, 95% confidence interval [CI], 1.08-1.58); however, among shift workers, night shift work was not associated with the risk of dementia (HR, 1.04, 95% CI, 0.73-1.47). We found no significant interaction between shift work and genetic predisposition to dementia on the primary outcome (P for interaction = 0.77). CONCLUSIONS: Shift work at baseline was associated with an increased risk of all-cause dementia. Among shift workers, there was no significant association between night shift work and the risk of dementia. The increased incidence of dementia in shift workers did not differ between participants in different genetic risk strata for dementia.

Sleep Traits, Night Shift Work and Lung Cancer Risk among Women: Results from a Population-Based Case-Control Study in France (The WELCA Study).

Circadian rhythm disruption due to night shift work and/or sleep disorders is associated with negative health outcomes including cancer. There is only scant evidence of an association with lung cancer, unlike breast and prostate cancer. We explore the role of sleep disorders and night shift work in lung cancer risk among women in a population-based case-control study, including 716 lung cancer cases and 758 controls. Multivariable logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI) associated with sleep duration per day (<7 h, 7−7.9 h, ≥8 h), a summary index of sleep disorders, chronotype, and night shift work exposure metrics. When compared to women with an average sleep duration of 7−7.9 h per day, the OR was 1.39 (95% CI 1.04−1.86) in long sleepers (≥8 h) and 1.16 (95% CI 0.86−1.56) in short sleepers (<7 h). Overall, lung cancer was not associated with the sleep disorder index, nor with night shift work, regardless of the duration of night work or the frequency of night shifts. However, elevated OR associated with the sleep disorder index were found in the subgroup of current smokers. The U-shaped association of lung cancer with sleep duration was more particularly pronounced among women who worked at night ≥5 years. Our findings suggested that sleep patterns are associated with lung cancer risk in women with a potential modifying effect by night shift work duration or tobacco smoking.

What do we know about the effect of night-shift work on cardiovascular risk factors? An umbrella review.

Objective: To evaluate the existing evidence on the effect of night-shift work and its subtypes (permanent and rotating) on cardiovascular risk factors: diabetes, lipid disorders, being overweight, hypertension, smoking habits, sedentariness, and occupational psychosocial stressors. Method: A Web of Sciences and Cochrane review library search was conducted to identify systematic reviews with or without meta-analysis dealing with the quantification of the link between night-shift work and the studied cardiovascular risk factors in working populations. We used the AMSTAR 2 to evaluate the quality of each review. The main results of the included systematic reviews were compiled in a summary structured around the different cardiovascular risk factors. Results: After selection, 33 systematic reviews were included: nine for diabetes, four for lipid disorders, nine for being overweight, four for hypertension, two for smoking habits, three for occupational psychosocial stressors and two for sedentariness. The results confirmed an excess risk of diabetes of about 10% regardless of the type of night work. A stated excess risk of being overweight at around 25% was also highlighted for shift workers overall, which could reach 38% among night-shift workers. An increased risk of obesity, estimated at 5% for night-shift workers and at 18% for rotating shift workers, was observed. An excess risk of hypertension was estimated at around 30% when considering the broad definition of shift work and when night periods were included in rotating shifts. The literature provided inconsistent results for the link between lipid disorders and night-shift work. Shift workers appeared to be more likely to smoke. The link between shift work and occupational psychosocial stressors was scarcely explored in the available studies. Sedentariness was scarcely considered in systematic reviews, which prevents any firm conclusions. Conclusion: The consequences of night work in terms of diabetes, being overweight/obesity and hypertension are established. Monitoring of these cardiovascular risk factors for these night-shift workers could be implemented by practitioners. In contrast, the links with lipid disorders, sedentariness, smoking habits, and occupational psychosocial stressors warrant further investigation. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021275212, PROSPERO (ID CRD42021275212).

Association between medication adherence to chronic diseases and shift-work schedules in the Korean working population.

Shift-working schedules are closely linked to chronic diseases, and only a few studies have investigated the association between working schedules and medication adherence in chronic diseases targeting workers. This study aimed to investigate whether shift-work schedules are associated with medication adherence in a working population with chronic conditions. The study participants (n = 11,460 person-years) were identified from the Korea Health Panel Study conducted from 2008 to 2018. Medication adherence was classified as good (2+) or poor (0 or 1) based on the 4-item Morisky Medication Adherence Scale. Work schedules were categorized as shifts and fixed daytime work. Its association with medication adherence was investigated using a generalized estimating equation model, generating odds ratios (OR) with 95% confidence intervals (CI). According to work schedules, shift workers were more likely than fixed-day workers to have poor medication adherence (adjusted OR = 1.16, 95% CI: 1.02-1.33). Regarding occupational classification, manual workers had a significantly higher risk of poor medication adherence than those in other occupational categories (adjusted OR = 1.27, 95% CI: 1.13-1.43). Among shift workers, the major reason for poor medication adherence was forgetting to take medication (SPR = 1.23, 95% CI: 1.07-1.38). Workers with irregular shift times are more vulnerable to poor medication adherence. Future studies are required to understand the mechanisms underlying this association and develop strategies to enhance medication adherence in the working population.