Circadian type, chronic fatigue, and serum IgM in the shift workers of an industrial organization

Latent Classes of Circadian Type and Presenteeism and Work-Related Flow Differences Among Clinical Nurses: A Cross-Sectional Study

OBJECTIVE

To classify the characteristics of circadian type among clinical nurses and examine their relationships with presenteeism and work-related flow.

METHODS

Using a cross-sectional design, 568 nurses were recruited through convenience sampling in January 2021 from three hospitals in Shandong Province, China. The data were collected using self-report measures, including the 11-item Circadian Type Inventory, Stanford Presenteeism Scale-6, and Work-Related Flow Inventory. Latent class analysis was performed to identify any clustering of circadian types. One-way analysis was performed to compare the differences between presenteeism and work-related flow in different circadian types.

RESULTS

Four latent classes were identified, including high response class (14.4%), high flexible class (20.1%), high languid class (51.1%), and low response class (14.4%). Regarding presenteeism, the high languid class had higher scores than others. Regarding work-related flow, the scores of high flexible class were higher than those of high languid class, while the differences in all three dimensions were statistically significant.

CONCLUSION

Although the shift work mode is not expected to change, nursing managers could use circadian type as a predictive index to select and employ individuals for shift work to enhance work performance and provide sufficient support to staff who are intolerant to shift work.

Effects of Mattress Material on Body Pressure Profiles in Different Sleeping Postures

OBJECTIVES

This study compared the body contact pressure profiles of 2 types of mattresses: latex and polyurethane.

METHODS

Twenty participants were required to lie down on the different mattresses in 3 different postures for 6 minutes, and their body contact pressure profiles were recorded with a pressure mat sensor.

RESULTS

The data indicated that the latex mattress was able to reduce the peak body pressure on the torso and buttocks and achieve a higher proportion of low-pressure regions compared with the polyurethane mattress.

CONCLUSIONS

Latex mattress reduced peak body pressure and achieved a more even distribution of pressure compared with polyurethane mattress across different sleeping postures.

Fatigue and on-duty injury among police officers: The BCOPS study

INTRODUCTION

Policing involves inherent physical and psychological dangers as well as occupational stressors that could lead to chronic fatigue. Although accounts of adverse events associated with police fatigue are not scarce, literature on the association between chronic fatigue and on-duty injury are limited.

METHODS

Participants were officers from the Buffalo Cardio-Metabolic Occupational Police Stress (BCOPS) Study. A 10-item questionnaire was administered to assess how tired or energetic the officers generally felt irrespective of sleep hours or workload. The questionnaire consisted of five positively worded and five negatively phrased items that measured feelings of vigor/energy and tiredness, respectively. Total as well as separate scores for positive and negative items were computed by summing scores of individual items. Payroll records documenting each officer's work history were used to assess occurrence of injury. Poisson regression was used to estimate prevalence ratios (PR) of injury.

RESULTS

Nearly 40% of officers reported feeling drained. Overall prevalence of on-duty injury during the past year was 23.9%. Injury prevalence showed a significant increasing trend across tertiles of total fatigue score: 19.6, 21.7, and 30.8% for lowest, middle and highest tertiles, respectively (trend p-value=0.037). After controlling for potential confounders, a 5-unit increase in total fatigue score was associated with a 12% increase in prevalence of injury which was marginally significant (p=0.075). A 5-unit increase in fatigue score of the positively worded items was associated with a 33% increase in prevalence of injury (PR=1.33, 95% CI: 1.04-1.70, p=0.022).

CONCLUSION

Officers who do not feel active, full of vigor, alert, or lively had a significantly higher prevalence of non-fatal work place injury compared to their counter parts. Practical applications: With additional prospective evidence, workplace interventions designed to enhance level of energy may reduce feelings of tiredness and hence may prevent workplace injury.

Klokwerk + study protocol: An observational study to the effects of night-shift work on body weight and infection susceptibility and the mechanisms underlying these health effects

BACKGROUND

Night-shift work may cause severe disturbances in the worker's circadian rhythm, which has been associated with the onset of health problems and diseases. As a substantial part of the workforce is exposed to night-shift work, harmful aspects of night-shift work should not be overlooked. The aim of the Klokwerk + study is to study the effects of night-shift work on body weight and infection susceptibility and the mechanisms underlying these health effects. First, we will study the relation between night-shift work exposure and body weight and between night-shift work exposure and infection susceptibility. Second, we will examine the mechanisms linking night-shift work exposure to body weight and infection susceptibility, with a specific focus on sleep, physical activity, diet, light exposure, vitamin D level, and immunological factors. Lastly, we will focus on the identification of biomarkers for chronic circadian disturbance associated with night-shift work.

METHODS/DESIGN

The design of this study is a prospective observational cohort study consisting of 1,960 health care workers aged 18-65 years. The study population will consist of a group of night-shift workers and an equally sized group of non-night-shift workers. During the study, there will be two measurement periods. As one of the main outcomes of this study is infection susceptibility, the measurement periods will take place at approximately the first (September/October) (T0) and the last month (April/May) (T1, after 6 months) of the flu season. The measurements will consist of questionnaires, anthropometric measurements, a smartphone application to determine infection susceptibility, food diaries, actigraphy, light sensors, and blood sample analyses.

DISCUSSION

The Klokwerk + study will contribute to the current need for high-quality data on the health effects of night-shift work and its underlying behavioral and physiological mechanisms. The findings can be the starting point for the development of interventions that prevent negative health effects caused by night-shift work. In addition, the identification of biomarkers indicative of loss of homeostasis due to circadian disturbance may be an important asset in monitoring the effects of such interventions.