The relationship between quality of sleep and night shift rotation interval

Night Shift Work and Sleep Disturbances in Women: A Scoping Review

This scoping review aimed to synthesize evidence on sleep disturbances in female shift workers. The update Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews was used. Twelve studies were included, four of which used actigraphy to assess sleep duration, efficiency, and latency. Seven studies evaluated the quality of sleep and three verified the sleepiness of women. This review adds to the body of evidence as the findings are homogeneous and allow a robust conclusion, suggesting that night shift work may be a potential factor for adverse effects on sleep of female shift workers.

Which Shiftwork Pattern Is the Strongest Predictor for Poor Sleep Quality in Nurses?

Shiftwork is related to an increased risk of several diseases, including gastric ulcers, myocardial infarction, and diabetes. Several shiftwork patterns are related to poor sleep quality, such as a quick returns or extended shifts. This study aimed to find the shiftwork patterns strongly associated with poor sleep quality amongst nurses. A cross-sectional analytical study was conducted among nurses working for at least one month. The sub-groups were the good sleep quality group (n = 150) and the poor sleep quality group (n = 472). Eligible participants were asked to complete a self-reported questionnaire comprising personal characteristics, job characteristics, shiftwork characteristics, and sleep quality. Factors associated with poor sleep quality were determined using logistic regression analysis. Two factors associated with poor sleep quality remained in the final model: viz., depression and backward rotational shift. The only independent factor for poor sleep quality was a backward rotational shift with an adjusted odds ratio (95% CI) of 1.946 (1.344, 2.871). In conclusion, compared with other shift patterns, backward shiftwork was the most significant factor associated with poor sleep quality and should be avoided.

Circadian secretion rhythm of GLP-1 and its influencing factors

Circadian rhythm is an inherent endogenous biological rhythm in living organisms. However, with the improvement of modern living standards, many factors such as prolonged artificial lighting, sedentarism, short sleep duration, intestinal flora and high-calorie food intake have disturbed circadian rhythm regulation on various metabolic processes, including GLP-1 secretion, which plays an essential role in the development of various metabolic diseases. Herein, we focused on GLP-1 and its circadian rhythm to explore the factors affecting GLP-1 circadian rhythm and its potential mechanisms and propose some feasible suggestions to improve GLP-1 secretion.

Poor Sleep Quality in Nurses Working or Having Worked Night Shifts: A Cross-Sectional Study

Night shifts are part of clinical care. It is unclear whether poor sleep quality of nurses working both consecutive night shifts and day shifts after quitting night shifts is common. In this cross-sectional study, Pittsburgh Sleep Quality Index (PSQI) was used to assess sleep quality as study outcome. Univariable and multivariable linear and logistic regressions were performed to compare PSQI score and prevalence of poor sleep quality between 512 nurses currently working consecutive night shifts and 174 nurses having worked night shifts in the past. The prevalence of poor sleep quality was 62.11% in nurses working consecutive night shifts and 55.75% in nurses having worked night shifts before. In multivariable regressions with adjustment for potential confounders, compared with nurses working consecutive night shifts, nurses having worked past night shifts reported decreased PSQI score [mean difference: −0.82 (95% CI: −1.27 to −0.38, p < 0.001)] and lower poor sleep quality [odds ratio (OR): 0.49 (95% CI: 0.29 to 0.80, p = 0.005)]. In nurses working consecutive night shifts, a rising curve that plateaued at the end was observed between years of consecutive night shifts and PSQI score, p = 0.004. To explore the change in PSQI score after quitting night shift, we constructed a hypothetical prospective cohort from the cross-sectional data. Here, 98 pairs of nurses with consecutive and past night shifts were matched for the number of night shift years, religion, marital status, living condition, hypertension, and hyperlipidemia. In each pair, a hypothetical change in PSQI score was calculated between the two types of nurses and hypothetical years after quitting night shifts was obtained from the matched nurse with past night shifts. A U-shaped curve between change in PSQI and years after quitting night shifts was observed, p = 0.007. The rising curve and U-shaped curve together formed an S-shaped curve, which mapped the change in sleep quality. These results based on the hypothetical cohort constructed from cross-sectional data suggested the presence of persistent poor sleep quality in night shift nurses. Also, we support early and continuous sleep hygiene education and reflection for an optimal strategy for when to cease working night shifts with regard to sleep-related problems.

Sleep and Association With Cardiovascular Risk Among Midwestern US Firefighters

INTRODUCTION

Cardiovascular disease is the leading cause of on-duty fatalities among U.S. firefighters. Research has demonstrated that many modifiable risk factors are contributors to the high prevalence of cardiometabolic risk factors. The current study aimed to assess whether sleep is associated with cardiometabolic risk factors among Indianapolis firefighters. The findings could support improving sleep hygiene in this population.

MATERIAL AND METHODS

This cross-sectional study was conducted from the baseline data of eligible firefighters enrolled in "Feeding America's Bravest", a Mediterranean diet lifestyle intervention within the Indiana Fire Departments. Participants' sleep quality was categorized as "good" (≤ 8 points) or "bad" (>8 points) by a sleep quality questionnaire based on some questions from Pittsburgh Sleep Quality Index. In addition, firefighters' sleep duration was stratified based on the number of hours slept per night (≤6 as "short sleep" or >6 hours as normal). Linear and logistic regression models were used to examine the association of sleep with cardiometabolic risk factors.

RESULTS

A total of 258 firefighters were included. Bad sleepers had higher weight, greater waist circumference, higher body mass index (BMI), and increased body fat (all p<0.01) compared to good sleepers. Similarly, participants with short sleep duration were heavier (p<0.02), had greater BMI (p<0.02) and increased body fat (p<0.04) compared with participants with normal sleep duration. Both bad and short sleepers had a higher prevalence of hypertension and obesity (p <0.05).

CONCLUSIONS

Our study supports that both sleep quality and quantity are associated with cardiometabolic risk among firefighters.

Nurses and Night Shifts: Poor Sleep Quality Exacerbates Psychomotor Performance

In Europe, 40% of health-care employees are involved in shift work. The altered sleep/wake rhythm of night-shift nurses is also associated with deteriorated cognitive efficiency. In this study, we examine the effects of the night shift on psychomotor performance, sleepiness, and tiredness in a large sample of shift-working nurses and evaluated if poor sleep quality, sex, age, or years on the job could impact on a better adaptation to shift work. Eighty-six nurses with 8-h-rapidly-rotating-shifts were evaluated at the end of three shifts (morning/afternoon/night) for sleepiness and tiredness. Sleepiness, as measured by the Karolinska Sleepiness Scale, and tiredness, as measured by the Tiredness Symptoms Scale, were more pronounced after the night shift. These increases were paralleled by lower attentional performance on the psychomotor vigilance task (PVT) after the night shift. While sex, age, and years on the job did not affect PVT performance after the night shift, lower sleep quality (Pittsburgh Sleep Quality, PSQI > 5) was associated with decreased performance. The high prevalence of altered sleep quality showed that nurses, and shift workers in general, are at risk for a poor sleep quality. The evaluation of sleep quality through PSQI could represent a rapid, inexpensive tool to assess health-care workers assigned to rotating night shifts or to evaluate nurses who coped poorly with night-shift work.

Morning and evening salivary melatonin, sleepiness and chronotype: A comparative study of nurses on fixed day and rotating night shifts

AIMS

To compare morning and evening salivary melatonin levels, sleep quality and chronotype between nurses working fixed day shifts and those working rotating night shifts.

BACKGROUND

Rotating night shift work is an inevitable part of nursing and is a major reason for disrupted sleep.

DESIGN

Cross-sectional comparative design.

PARTICIPANTS AND SETTINGS

We used cluster sampling to recruit 520 female nurses working fixed day and rotating night shifts in the United Arab Emirates.

METHODS

Morning and evening melatonin were measured from corresponding saliva samples. The Pittsburgh Sleep Quality Index used to evaluate sleep quality and self-assessment of preferred circadian times was used to assess participants' chronotypes. Data were collected between October 2017-December 2018.

RESULTS

Rotating night shift nurses had significantly lower evening melatonin compared with the fixed day shift group. No significant difference was found in sleep quality between the groups, although more participants in the rotating night shift group (N = 110, 42.31%) expressed better sleep quality than those in the fixed day group (N = 90, 36.00). Participants in the rotating night shift group expressed better subjective sleep, longer sleep duration, less disturbed sleep and better daily function (p > .05) than the fixed day group. Rotating night shift participants were more likely to have evening or intermediate chronotypes and more likely to report alignment of shift work to their chronotype compared with fixed day shift participants (p = .001). Longer shift duration, marital status and city location were associated with reduced evening melatonin among nurses on rotating night shifts.

CONCLUSION

Rotating night shift nurses showed evidence of better sleep than those from the fixed day shift. Proper shift assignment, chronotype and alignment with shift work appeared to produce better sleep quality.

IMPACT

Organizational policy must consider a novel model for work schedules that allow adequate off-duty days for sleep recovery among nurses.

A Bayesian assessment of occupational health surveillance in workers exposed to silica in the energy and construction industry

Medical records generated during occupational health surveillance processes have large amounts of unexploited information that can help to reduce silica-related health risks and many occupational diseases. The methodology applied in this study consists in analyzing through machine learning techniques a database with 70,000 medical examinations from workers in the energy and construction industry in Spain. First, a general unsupervised Bayesian model is built and node force analysis is used to identify the factors with the greatest impact on the worker's health surveillance process. Second, a predictive Bayesian model is created and mutual information is employed to assess the more relevant factors affecting the medical capability of workers exposed to silica dust. The lung auscultation and the breathing exploration are the two factors that influence the most the medical capability of silica-exposed employees. Probabilistic inference shows a remarkable gender effect, where women present more resilience towards occupational diseases than men showing a higher proportion of normal results in certain key factors, such as body mass index (♀49.73%, ♂25.17%) or spirometry (♀53.73%, ♂48.91%). Finally, environmental conditions demonstrate to have a major influence on spatial variability of occupational diseases. The design of health prevention programs based on geographical variations can be crucial to the attainment of an ongoing and sustained healthier workforce with a reduction in the number of chronic workplace illnesses.

The relationship between serum vitamin D levels and sleep quality in fixed day indoor field workers in the electronics manufacturing industry in Korea

Background

Although recent studies have investigated the influence of vitamin D on sleep patterns, there is a lack of research on the relationship between vitamin D and sleep patterns in Korean workers. This study focused on the relationship between serum vitamin D levels and sleep in fixed day indoor field workers in the electronics manufacturing industry in Korea.

Methods

The 1472 subjects who were included in this study were selected from fixed day workers in the electronics manufacturing industry who had received a worker’s special health examination at a hospital in Changwon, South Gyeongsang Province between January 2015 and December 2015. Nighttime workers and those who showed symptoms of depression were excluded from this study. The sociodemographic and lifestyle variables of the participants were investigated, including age, sex, marital status, level of education, body mass index, smoking habits, alcohol consumption habits, and regular exercise. Work-related factors were evaluated, such as employee tenure and occupational stress. Serum 25-hydroxyvitamin D was measured as an indicator of vitamin D levels, and quality of sleep was evaluated using the Pittsburgh Sleep Quality Index (PSQI) translated into Korean.

Results

The subjects had a mean serum vitamin D level of 13.70 ± 5.93 ng/mL. Vitamin D deficiency, defined as a serum vitamin D level of <10 ng/mL, was found in 24.8% of males and significantly more frequently in females (47.6%). Poor sleep quality was reported by 19.8% of participants with serum vitamin D levels ≥10 ng/mL and by 21.7% of those with serum vitamin D levels <10 ng/mL, which was a significant difference (P = .007). Multiple logistic regression analysis adjusting for significant variables found that poor sleep quality was more likely in those with vitamin D deficiency than those with higher serum vitamin D levels (odds ratio = 1.36; 95% CI, 1.01–1.82). A comparison of serum vitamin D levels and PSQI components showed that the mean scores for subjective sleep quality, sleep latency, and sleep duration were significantly higher in the vitamin D-deficient participants, indicating that the vitamin D-deficient participants had poorer sleep quality.

Conclusions

This study investigated serum vitamin D levels in fixed day indoor field workers in the manufacturing industry in Korea and analyzed the relationship of vitamin D deficiency with sleep quality. A significant correlation was found between serum vitamin D deficiency and poor sleep quality. Based on the results of this study, sleep disorder management for workers can be improved by providing regular examinations checking their serum vitamin D levels and supplying vitamin D to workers with serum vitamin D deficiency to enhance their quality of sleep.

Work, sleep, and cholesterol levels of U.S. long-haul truck drivers

Long-haul truck drivers in the United States experience elevated cardiovascular health risks, possibly due to hypercholesterolemia. The current study has two objectives: 1) to generate a cholesterol profile for U.S. long-haul truck drivers; and 2) to determine the influence of work organization characteristics and sleep quality and duration on cholesterol levels of long-haul truck drivers. Survey and biometric data were collected from 262 long-haul truck drivers. Descriptive analyses were performed for demographic, work organization, sleep, and cholesterol measures. Linear regression and ordinal logistic regression analyses were conducted to examine for possible predictive relationships between demographic, work organization, and sleep variables, and cholesterol outcomes. The majority (66.4%) of drivers had a low HDL (<40 mg/dL), and nearly 42% of drivers had a high-risk total cholesterol to HDL cholesterol ratio. Sleep quality was associated with HDL, LDL, and total cholesterol, and daily work hours were associated with LDL cholesterol. Workday sleep duration was associated with non-HDL cholesterol, and driving experience and sleep quality were associated with cholesterol ratio. Long-haul truck drivers have a high risk cholesterol profile, and sleep quality and work organization factors may induce these cholesterol outcomes. Targeted worksite health promotion programs are needed to curb these atherosclerotic risks.

Influence of night duty on endoscopic therapy for bile duct stones

AIM

To examine the influence of night duty (ND) on endoscopic therapy for biliary duct stones.

METHODS

The subjects consisted of 133 patients who received initial endoscopic therapy for biliary duct stones performed by eight endoscopists after they had been on (ND group, n = 34 patients) or not [day duty (DD) group, n = 99 patients]. Patient characteristics (age, gender, history of abdominal surgery, transverse diameter of the largest stone, number of stones), years of experience of the endoscopists, endoscopic procedures [sphincterotomy, papillary balloon dilation (EPBD), papillary large balloon dilation (EPLBD)], and outcomes of initial endoscopy (procedure time; rate of stone removal by the first endoscopist; procedure success rate by the first endoscopist: removal of stones or endoscopic retrograde biliary drainage; rate of final stone removal; final procedure success rate; complications; hospitalization after the procedure) were compared retrospectively between the two groups. History of abdominal surgery and treatment outcomes were also compared between the groups for each of the four endoscopists who performed most of the procedures in the ND group.

RESULTS

There were no significant differences regarding the number of treatments performed by each endoscopist or the years of experience between the ND and DD groups. The frequency of endoscopic retrograde cholangiopancreatography procedures did not differ significantly between the groups. There were also no significant differences regarding patient characteristics: age, gender, history of abdominal surgery (ND 7: Billroth II 4, R-Y 3; DD 18: double tract reconstruction 1, Billroth I 3, Billroth II 6, R-Y 7, duodenoduodenostomy for annular pancreas 1), transverse diameter of largest stone, and number of stones between the two groups. Among the treatment procedures, the endoscopic sphincterotomy and EPBD rates did not differ significantly between the groups. However, EPLBD was performed more frequently in the ND group [47.1% (16/34) vs 19.2% (19/99)]. Regarding outcomes, there were no significant differences in the rate of stone removal, procedure success rate, complications (ND: pancreatitis 1; DD: pancreatitis 6, duodenal bleeding 1, decreased blood pressure 1, hypoxia 2), or hospitalization after the procedure. However, the procedure time was significantly longer in the ND group (71.5 ± 44.7 vs 54.2 ± 28.8). Among the four endoscopists, there were no significant differences in patient history of abdominal surgery, removal of stones, or procedure success rate. However, the procedure time for one endoscopist was significantly longer in the ND group.

CONCLUSION

The time required for endoscopic therapy for bile duct stones might be influenced by ND.