Decreased psychomotor vigilance of female shift workers after working night shifts

We compared psychomotor vigilance in female shift workers of the Bergmannsheil University Hospital in Bochum, Germany (N = 74, 94% nurses) after day and night shifts. METHODS:Participants performed a 3-minute Psychomotor Vigilance Task (PVT) test bout at the end of two consecutive day and three consecutive night shifts, respectively. Psychomotor vigilance was analyzed with respect to mean reaction time, percentage of lapses and false starts, and throughput as an overall performance score, combining reaction time and error frequencies. We also determined the reaction time coefficient of variation (RTCV) to assess relative reaction time variability after day and night shifts. Further, we examined the influence of shift type (night vs. day) by mixed linear models with associated 95% confidence intervals (CI), adjusted for age, chronotype, study day, season, and the presence of obstructive sleep apnea (OSA). RESULTS:At the end of a night shift, reaction times were increased (&beta; = 7.64; 95% CI 0.94; 14.35) and the number of lapses higher compared to day shifts (exp(&beta;) = 1.55; 95% CI 1.16-2.08). By contrast, we did not observe differences in the number of false starts between day and night shifts. Throughput was reduced after night shifts (&beta; = -15.52; 95% CI -27.49; -3.46). Reaction times improved across consecutive day and night shifts, whereas the frequency of lapses decreased after the third night. RTCV remained unaffected by both, night shifts and consecutive shift blocks. DISCUSSION:Our results add to the growing body of literature demonstrating that night-shift work is associated with decreased psychomotor vigilance. As the analysis of RTCV suggests, performance deficits may selectively be driven by few slow reactions at the lower end of the reaction time distribution function. Comparing intra-individual PVT-performances over three consecutive night and two consecutive day shifts, we observed performance improvements after the third night shift. Although a training effect cannot be ruled out, this finding may suggest better adaptation to the night schedule if avoiding fast-changing shift schedules.</p

Night Shift Work Affects Urine Metabolite Profiles of Nurses with Early Chronotype

Night shift work can have a serious impact on health. Here, we assess whether and how night shift work influences the metabolite profiles, specifically with respect to different chronotype classes. We have recruited 100 women including 68 nurses working both, day shift and night shifts for up to 5 consecutive days and collected 3640 spontaneous urine samples. About 424 waking-up urine samples were measured using a targeted metabolomics approach. To account for urine dilution, we applied three methods to normalize the metabolite values: creatinine-, osmolality- and regression-based normalization. Based on linear mixed effect models, we found 31 metabolites significantly (false discovery rate <0.05) affected in nurses working in night shifts. One metabolite, acylcarnitine C10:2, was consistently identified with all three normalization methods. We further observed 11 and 4 metabolites significantly associated with night shift in early and late chronotype classes, respectively. Increased levels of medium- and long chain acylcarnitines indicate a strong impairment of the fatty acid oxidation. Our results show that night shift work influences acylcarnitines and BCAAs, particularly in nurses in the early chronotype class. Women with intermediate and late chronotypes appear to be less affected by night shift work

Epidemiological Evidence for Work Load as a Risk Factor for Osteoarthritis of the Hip: A Systematic Review

Osteoarthritis of the hip (OA) is a common degenerative disorder of the joint cartilage that presents a major public health problem worldwide. While intrinsic risk factors (e.g, body mass and morphology) have been identified, external risk factors are not well understood. In this systematic review, the evidence for workload as a risk factor for hip OA is summarized and used to derive recommendations for prevention and further research.Epidemiological studies on workload or occupation and osteoarthritis of the hip were identified through database and bibliography searches. Using pre-defined quality criteria, 30 studies were selected for critical evaluation; six of these provided quantitative exposure data.Study results were too heterogeneous to develop pooled risk estimates by specific work activities. The weight of evidence favors a graded association between long-term exposure to heavy lifting and risk of hip OA. Long-term exposure to standing at work might also increase the risk of hip OA.It is not possible to estimate a quantitative dose-response relationship between workload and hip OA using existing data, but there is enough evidence available to identify job-related heavy lifting and standing as hazards, and thus to begin developing recommendations for preventing hip OA by limiting the amount and duration of these activities. Future research to identify specific risk factors for work-related hip OA should focus on implementing rigorous study methods with quantitative exposure measures and objective diagnostic criteria

Schichtarbeit und Krebserkrankungen

&lt;jats:title&gt;Zusammenfassung&lt;/jats:title&gt;&lt;jats:p&gt;Die gesundheitlichen Auswirkungen von Schicht- und Nachtarbeit sind Gegenstand vieler wissenschaftlicher Untersuchungen. Das Spektrum möglicher Erkrankungen und Endpunkte, die mit Schicht- und Nachtarbeit assoziiert sind, reicht von chronischen Erkrankungen wie Krebs, Herz-Kreislauf-Erkrankungen über Schlafstörungen, psychische Belastungen bis hin zu Reproduktionsstörungen und Unfällen. Im Juni 2019 stufte die Internationale Krebsagentur (IARC) Nachtarbeit als wahrscheinlich krebserregend ein (Gruppe 2A) und bestätigte damit ihre Einschätzung aus dem Jahr 2007. Die Expertengruppe der IARC weist dabei auf die immer noch sehr heterogenen Studienergebnisse hin. Während der überwiegende Teil der populationsbasierten Fall-Kontroll-Studien positive Assoziationen zwischen Schichtarbeit und Krebserkrankungen zeigte, wurde in vielen Kohorten-Studien keine Assoziation beobachtet. Die Frage, ob erhöhte Krebsrisiken tatsächlich auf Schicht- oder Nachtarbeit zurückgeführt werden können, kann daher zurzeit nicht zweifelsfrei beantwortet werden. Der folgende Beitrag gibt einen Überblick zu offenen Fragen und Aspekten der Schichtarbeitsforschung am Beispiel von Krebserkrankungen und diskutiert die aktuelle arbeitsmedizinische Einschätzung.&lt;/jats:p&gt

Decreased psychomotor vigilance of female shift workers after working night shifts.

BackgroundWe compared psychomotor vigilance in female shift workers of the Bergmannsheil University Hospital in Bochum, Germany (N = 74, 94% nurses) after day and night shifts.MethodsParticipants performed a 3-minute Psychomotor Vigilance Task (PVT) test bout at the end of two consecutive day and three consecutive night shifts, respectively. Psychomotor vigilance was analyzed with respect to mean reaction time, percentage of lapses and false starts, and throughput as an overall performance score, combining reaction time and error frequencies. We also determined the reaction time coefficient of variation (RTCV) to assess relative reaction time variability after day and night shifts. Further, we examined the influence of shift type (night vs. day) by mixed linear models with associated 95% confidence intervals (CI), adjusted for age, chronotype, study day, season, and the presence of obstructive sleep apnea (OSA).ResultsAt the end of a night shift, reaction times were increased (β = 7.64; 95% CI 0.94; 14.35) and the number of lapses higher compared to day shifts (exp(β) = 1.55; 95% CI 1.16-2.08). By contrast, we did not observe differences in the number of false starts between day and night shifts. Throughput was reduced after night shifts (β = -15.52; 95% CI -27.49; -3.46). Reaction times improved across consecutive day and night shifts, whereas the frequency of lapses decreased after the third night. RTCV remained unaffected by both, night shifts and consecutive shift blocks.DiscussionOur results add to the growing body of literature demonstrating that night-shift work is associated with decreased psychomotor vigilance. As the analysis of RTCV suggests, performance deficits may selectively be driven by few slow reactions at the lower end of the reaction time distribution function. Comparing intra-individual PVT-performances over three consecutive night and two consecutive day shifts, we observed performance improvements after the third night shift. Although a training effect cannot be ruled out, this finding may suggest better adaptation to the night schedule if avoiding fast-changing shift schedules

Framework for integrating human and animal data in chemical risk assessment

Although regulatory agencies formally encourage the integration of all available data in chemical risk assessment, consistent implementation of this practice has been constrained by the lack of a clear, systematic method for doing so. In this paper, we describe a methodology for evaluating, classifying and integrating human and animal data into the risk assessment process that incorporates: (1) a balanced appraisal of human and animal data, (2) relevance to different stages of the risk assessment process, and (3) accommodation for different data quality requirements. The proposed framework offers a flexible, step-wise approach for determining which set of available data best support the chemical risk assessment that involves the rating and relative ranking of human and animal data quality. The evaluation of human data incorporates seven data quality elements, nature and specificity of the lead effect; evaluation of animal data incorporates data quality and relevance to humans. Results of simulations with selected chemicals previously evaluated in a formal risk assessment generally agreed with existing regulatory guidance. Application of the proposed framework across a wider range of chemical agents will improve transparency of the risk assessment process and validity of results, while informing continuous refinements to this evolving methodology

Schichtarbeit und Krebserkrankungen

Die gesundheitlichen Auswirkungen von Schicht- und Nachtarbeit sind Gegenstand vieler wissenschaftlicher Untersuchungen. Das Spektrum möglicher Erkrankungen und Endpunkte, die mit Schicht- und Nachtarbeit assoziiert sind, reicht von chronischen Erkrankungen wie Krebs, Herz-Kreislauf-Erkrankungen über Schlafstörungen, psychische Belastungen bis hin zu Reproduktionsstörungen und Unfällen. Im Juni 2019 stufte die Internationale Krebsagentur (IARC) Nachtarbeit als wahrscheinlich krebserregend ein (Gruppe 2A) und bestätigte damit ihre Einschätzung aus dem Jahr 2007. Die Expertengruppe der IARC weist dabei auf die immer noch sehr heterogenen Studienergebnisse hin. Während der überwiegende Teil der populationsbasierten Fall-Kontroll-Studien positive Assoziationen zwischen Schichtarbeit und Krebserkrankungen zeigte, wurde in vielen Kohorten-Studien keine Assoziation beobachtet. Die Frage, ob erhöhte Krebsrisiken tatsächlich auf Schicht- oder Nachtarbeit zurückgeführt werden können, kann daher zurzeit nicht zweifelsfrei beantwortet werden. Der folgende Beitrag gibt einen Überblick zu offenen Fragen und Aspekten der Schichtarbeitsforschung am Beispiel von Krebserkrankungen und diskutiert die aktuelle arbeitsmedizinische Einschätzung.The health effects of shift and night work have been the subject of many scientific studies. The spectrum of possible diseases and endpoints associated with shift and night work range from chronic diseases, such as cancer and cardiovascular diseases, over sleep disorders and psychological stress up to reproductive disorders and accidents. In June 2019 the International Agency for Research on Cancer (IARC) classified night work as probably carcinogenic to humans (group 2A), thus confirming its previous assessment from 2007. The IARC expert group pointed out the continuing large heterogeneity of the study results. The majority of population-based case-control studies showed positive associations between shift work and cancer, whereas in many cohort studies no such associations were observed. Therefore, the question as to whether increased cancer risks can actually be attributed to shift or night work cannot yet be answered with certainty. This article provides an overview of open questions and aspects of shift work research using the example of cancer and discusses the current implications for occupational health