Firefighters experience stressful job demands. Many of them work in shifts that can extend to 96-hour rotations. Firefighters also tend to suffer from poor sleep quality and psychological distress; however, there are conflicting findings on how these factors may relate to each other. The purpose of this quantitative survey study was to examine the relation between symptoms of depression, anxiety, posttraumatic stress disorder (PTSD), and alcohol abuse to shift duration in firefighters who work 24-hour shifts compared to those who work 48-hour shifts, with sleep quality as a mediating variable. The repair and restoration theory of sleep was the theoretical framework. One hundred forty-three adult firefighters employed in the midwestern region of the United States completed a demographic questionnaire, the Pittsburgh Sleep Quality Index, and the Psychiatric Diagnostic Screening Questionnaire using an online survey to help ensure anonymity. The results of a multivariate analysis of covariance indicated that anxiety [F (1, 140) = 4.042, p = .042; F (1, 140) = 4.521, p = .035] and alcohol abuse [F (1, 140) = 12.497, p = .001; F (1, 140) = 12.686, p =.001] were both significantly related to shift duration before and after controlling for sleep quality, with individuals in the longer shifts reporting more distress. PTSD was not significantly different between the groups; however, a trend emerged for longer shifts to be related to more distress after controlling for sleep quality. The findings of this research may be used to promote social change by improving the lives of firefighters and the communities they serve, as well as educating decision makers with information needed to address potential mental health burdens of shiftwork in this population.

Research into the quality of life of nurses working at night has received scant attention to date. Apart from studies relating to changes in circadian rhythms of night nurses, very few other aspects of the complex adaptive process have been given serious consideration. Yet, knowledge of that adaptive process is a prerequisite for the selection of staff, and for the design of an appropriate educational programme and staff development strategy. This study looks first at methods of describing the quality of life in general, in order to aim at criteria for evaluation which do not impose the conventional position that day work is proper work. In the light of these criteria, preconceptions and limitations which surround shift work in general are identified and discussed. Night nurses as a group are then subjected to a more intensive examination, including a theoretical review; a survey of a population of one-hundred and sixty-one night nurses and selected interviews; and an account of a pilot study of a potential curriculum. Results of the survey indicate that nurses who show a preference for night work and who selfselect these hours on a permanent basis are more likely to derive challenge from and express greater satisfaction with their work, than those on alternative day and night shifts. Further, there is a stable population of workers who choose night work above all other options as a source of personal satisfaction, freedom and challenge. In the light of these findings, recommendations are made as to the selection, education and development of hospital night staff.

<p>Syftet med studien var att beskriva ambulanspersonalens självskattning/upplevelse av smärta i rygg, leder och muskler samt sömn, vila och återhämtning. Ytterligare ett syfte var att undersöka om det finns några skillnader i nämnda besvär relaterat till kön och yrkeskategori. Data samlades in med enkäter och personal vid fyra ambulansstationer i Mellansverige deltog i studien. Sammanlagt delades 110 enkäter ut och 89 enkäter besvarades (svarsfrekvens 81 %). Resultatet avseende själskattad smärta visade att 53 personer (59,6 %) uppgav att de hade haft ländryggsbesvär de senaste 12 månaderna. Trettionio personer (43,6 %) uppgav nacksmärta de senaste12 månaderna. Tjugonio personer (32,6 %) uppgav skuldra/axelsmärta. Resultatet visade ingen statistisk signifikant skillnad mellan kön och yrkeskategorier. Resultatet avseende sömn visade att 72 personer (81 %) upplevde att de sov ganska bra till mycket bra. Cirka hälften av de 89 deltagarna 53 % uppgav att de kunde återhämta sig efter varje arbetspass och under lediga perioder uppgav 49 personer (55 %) att de kunde återhämta sig i stort sett varje period. Resultatet visade ingen statistisk signifikant skillnad mellan kön eller yrkeskategorier när det gällde smärt – och sömnbesvär.</p><p>Slutsats: För att förbättra arbetsmiljön för ambulanspersonal bör åtgärder inriktas mot belastningsergonomiska faktorer i arbetet.</p> / <p>The purpose of the study was to describe the ambulance personnel’s self-assessment/experiences of pain in the back, joints and muscles as well as sleep, rest and recovery. A further aim was to investigate whether there are any differences in the problems related to gender and profession. Data were collected with questionnaires, and personnel at four ambulance stations in central Sweden participated in the study. A total of 110 questionnaires were distributed, and the overall response rate was 81 %. The results for soul-rated pain showed that 53 persons (59, 6 %) reported low back pain in the last 12 months. Thirty-nine persons (43, 6 %) reported neck pain the past 12 months. Twenty-nine persons (32, 6 %) reported shoulder/shoulder pain. The results show no statistically significant difference between gender and occupational categories. The results showed that 72 persons (81 %) experience that they slept pretty good to very good. Approximately half of the 89 participants, 53 % reported they could recover after each session and during her free period reported 49 persons (55 %) experience that they could recover almost every period. The results show no statistically significant difference between gender or occupational categories regarding.</p><p>Conclusion: To improve the work environment for ambulance personnel, measures should be focused on load and strain ergonomic factors.</p>

Shift work is a work schedule being the opposite of normal daytime work, often defined as working time outside normal daytime hours (06:00 to 18:00). In recent years, shift work has been associated with an increased risk of numerous chronic conditions including for example cardiovascular disease, some types of cancer, type II diabetes, and the metabolic syndrome. While some studies on the association between shift work and chronic disease have found results supporting it, others have not. Therefore, more research is needed to clarify potential associations.The aim of this thesis was to further study the proposed association between shift work and cardiovascular disease. This was addressed by performing two studies, one analysing if shift workers had an increased risk of ischemic stroke compared to day workers. The other study analysed whether shift workers had an increased risk of short-term mortality (case fatality) after a myocardial infarction compared to day workers. The studies were performed using logistic regression analysis in two different case-control databasesThe findings from the first study indicated that shift workers did not have an increased risk of ischemic stroke. The findings from the second study showed that male shift workers had an increased risk of death within 28 days after a myocardial infarction; the results did not indicate an increased risk for female shift workers. The results from both studies were adjusted for both behavioural and medical risk factors without affecting the results. The findings from this thesis provide new evidence showing that male shift workers have an increased risk of death 28 days after a myocardial infarction, however more research is needed to clarify and characterise any such potential associations.

Syftet med studien var att beskriva ambulanspersonalens självskattning/upplevelse av smärta i rygg, leder och muskler samt sömn, vila och återhämtning. Ytterligare ett syfte var att undersöka om det finns några skillnader i nämnda besvär relaterat till kön och yrkeskategori. Data samlades in med enkäter och personal vid fyra ambulansstationer i Mellansverige deltog i studien. Sammanlagt delades 110 enkäter ut och 89 enkäter besvarades (svarsfrekvens 81 %). Resultatet avseende själskattad smärta visade att 53 personer (59,6 %) uppgav att de hade haft ländryggsbesvär de senaste 12 månaderna. Trettionio personer (43,6 %) uppgav nacksmärta de senaste12 månaderna. Tjugonio personer (32,6 %) uppgav skuldra/axelsmärta. Resultatet visade ingen statistisk signifikant skillnad mellan kön och yrkeskategorier. Resultatet avseende sömn visade att 72 personer (81 %) upplevde att de sov ganska bra till mycket bra. Cirka hälften av de 89 deltagarna 53 % uppgav att de kunde återhämta sig efter varje arbetspass och under lediga perioder uppgav 49 personer (55 %) att de kunde återhämta sig i stort sett varje period. Resultatet visade ingen statistisk signifikant skillnad mellan kön eller yrkeskategorier när det gällde smärt – och sömnbesvär. Slutsats: För att förbättra arbetsmiljön för ambulanspersonal bör åtgärder inriktas mot belastningsergonomiska faktorer i arbetet. / The purpose of the study was to describe the ambulance personnel’s self-assessment/experiences of pain in the back, joints and muscles as well as sleep, rest and recovery. A further aim was to investigate whether there are any differences in the problems related to gender and profession. Data were collected with questionnaires, and personnel at four ambulance stations in central Sweden participated in the study. A total of 110 questionnaires were distributed, and the overall response rate was 81 %. The results for soul-rated pain showed that 53 persons (59, 6 %) reported low back pain in the last 12 months. Thirty-nine persons (43, 6 %) reported neck pain the past 12 months. Twenty-nine persons (32, 6 %) reported shoulder/shoulder pain. The results show no statistically significant difference between gender and occupational categories. The results showed that 72 persons (81 %) experience that they slept pretty good to very good. Approximately half of the 89 participants, 53 % reported they could recover after each session and during her free period reported 49 persons (55 %) experience that they could recover almost every period. The results show no statistically significant difference between gender or occupational categories regarding. Conclusion: To improve the work environment for ambulance personnel, measures should be focused on load and strain ergonomic factors.

Background: Long-term night shift work has been associated with multiple cancer sites, including breast, prostate, colon and endometrial. The mechanism for this effect is hypothesized to include the hormone melatonin; where increased light at night exposure during shift work reduces melatonin production and decreased melatonin levels are associated with increased cancer risk. In addition, physical activity has been shown to reduce cancer risk and existing laboratory studies indicate it has the potential to influence melatonin levels. Methods: A cross-sectional study of light intensity exposure, physical activity and melatonin levels was conducted among 61 rotating shift nurses at Kingston General Hospital. Light intensity exposure was measured using a light intensity data logger and melatonin concentrations were measured from urine and saliva samples, collected over a 24-hour period. Physical activity was assessed from a study questionnaire and one-day diary. Results: A statistically significant inverse association between light exposure and urinary melatonin levels was observed; however, the relationship was no longer significant when stratified by shift group. Analysis of salivary melatonin levels demonstrated that circadian rhythms of melatonin production in night workers were not altered in timing, such that peak melatonin production occurred at night. No association between light exposure and the magnitude of salivary melatonin variation was observed. The relationship between recent physical activity and melatonin differed by shift group, with a positive association seen among day workers, while an inverse relationship was seen among night workers. There was no association between usual physical activity and melatonin in either shift group. Finally, no significant correlation was observed between sleep duration and melatonin among either day or night workers. Conclusions: While this study demonstrated an inverse relationship between light intensity and melatonin, the comparison of functional time points between day and night workers meant that differences in urinary melatonin levels between shift groups could be attributed to differences in the time of day when urine samples were collected. No consistent relationship between recent or usual physical activity and melatonin levels was observed in either shift group. Sleep duration was not correlated with urinary melatonin levels, suggesting it cannot be used as a proxy for melatonin production. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2008-06-26 08:39:21.645

Background: In 2007, the International Agency for Research on Cancer (IARC) classified long-term shift work as a probable human carcinogen; however, the mechanism through which shift work potentially increases cancer risk is not known. One hypothesis is that diminished melatonin production may be involved, possibly as a result of exposure to light during night work. Experimental studies suggest a link between melatonin and peptides in the insulin-like growth factor (IGF) family, also implicated in carcinogenesis. This research aimed to describe the distributions of circulating concentrations of insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3) and their associations with urinary melatonin as possible intermediates in the pathway between work at night and breast cancer. Methods: A cross-sectional study was conducted among 85 premenopausal nurses working a rotating shift pattern of two 12-hour days, two 12-hour nights, and five days off. Once during both the summer and winter seasons, melatonin metabolites were measured in urine samples and circulating concentrations of IGF-I and IGFBP-3 were determined from serum samples. Weight and height were measured by the study coordinator, while a questionnaire and study diaries were used to collect all other covariate information. Predictors of IGF levels were identified using multivariate mixed effects modeling and relationships between melatonin and the IGFs were investigated using Spearman’s rank correlation and multivariate mixed effects modeling. Results: Both age (β = -3.6, p < 0.0001) and current OC use (β = -40.8, p = 0.003) were associated with decreases in circulating IGF-I, while levels of IGF-I were increased in the winter months (β = 26.3, p = 0.02). A positive relationship between recent alcohol consumption and serum IGFBP-3 was also suggested (β = 197.8, p = 0.05). Neither Spearman’s rank correlations nor mixed effects modeling indicated that urinary melatonin was a determinant of serum IGFs. Conclusions: Age, season, and current OC use were observed to predict circulating IGF-I, while recent alcohol consumption was a determinant of IGFBP-3 levels. A relationship between melatonin and IGFs, theorized as a component of the mechanism linking shift work and cancer, was not supported by the results of this project. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2012-05-30 15:29:31.253

Background: Shift work has recently been identified as a breast cancer risk factor, where meta-analysis has indicated an approximately 50% increased risk among long-term shift workers. However, additional studies with more comprehensive methods of shift work exposure assessment are needed to capture the diversity of shift patterns. The hypothesized mechanism for this relationship involves chronodisruption (altered circadian rhythms), where increased exposure to light at night during night shifts may decrease production of the cancer-protective hormone melatonin. Further, coordination of circadian rhythms, including melatonin production, is governed by the interactions of a set of central clock genes. Recent studies have suggested that variants in clock genes are associated with cancer risk at multiple sites, including breast cancer, although few studies have considered potential interactions with shift work. Methods: This thesis examined relationships of both shift work and clock gene polymorphisms (and their interactions) with breast cancer risk in a case-control study of 1,142 cases and 1,178 controls. The association between light exposure and melatonin production was also investigated in a longitudinal biomarker study conducted among 123 nurses working a two-day, two-night rotating shift pattern. Results: In the case-control study, an association between breast cancer and ≥30 years of shift work (OR = 2.20, 95%CI = 1.13 – 4.28) was detected, although no relationship with short (0 – 14 years) or medium (15 – 29 years) term shift work was observed. As well, variants in 14 clock-related genes were not associated with breast cancer and there were no apparent interactions with shift work history. In the biomarker study, both peak melatonin levels and daily change in melatonin levels were similar when nurses were working their day and night shifts. Further, on the night shift, a slight inverse relationship between light and change in melatonin was observed (p = 0.04). Conclusions: Taken together, these results contribute to the understanding of both the association between shift work and breast cancer, and the biologic mechanisms underlying this relationship. Since shift work is required for many occupations, understanding the mechanisms through which it impacts breast cancer is important to the development of healthy workplace policy. / Thesis (Ph.D, Community Health & Epidemiology) -- Queen's University, 2012-09-26 20:59:40.209

SAMMANFATTNING Bakgrund Att arbeta skift har visat sig vara en stressfaktor som påverkar både sömn och hälsa negativt och inom sjukvården kan även patientsäkerheten äventyras om personalen är utmattad på grund av sömnbrist. Syfte Syfte med denna litteraturstudie var att beskriva vilka faktorer som påverkar sömnen och kan medföra sömnstörningar, samt vilka preventiva åtgärder som kan leda till förbättrad sömn hos skiftarbetande vårdspersonal. Metod Resultatet bygger på tio vetenskapliga artiklar publicerade under åren 2007-2013. Dessa söktes genom databaserna Cinahl, PsykINFO och PubMed. Resultat I analysen av artiklarna framkom att skiftarbete som inkräktar på normala sömntider har en uppenbart skadlig effekt på sömnen med svårigheter att somna och sömnighet under både arbetstid och ledighet. Utmärkande var att stigande ålder och låg stresströskel (hardiness) ökade risken för sömnstörningar. Att ges möjlighet till tupplur under nattpass var en viktig åtgärd för att förebygga trötthet och främja hälsan hos skiftarbetande vårdpersonal. Slutsats Eftersom skiftarbete i sig har en uppenbart skadlig effekt på sömnen så är det av största vikt att ge vårdpersonalen bästa möjliga förutsättningar för att bibehålla sin hälsa på sikt. Förutom att planera för bra skiftscheman med schemalagd rast samt möjlighet att sova på nattpassen, bör man ta hänsyn till vårdpersonalens ålder och stresstålighet (hardiness). / ABSTRACT Background Working shift has been shown to be a stressor that impacts both sleep and health negatively and within the healthcare also the patient safety could be affected if the personnel are fatigued due to sleep deprivation. Aim The aim of the literature review was to describe which factors that influences sleep and can lead to insomnia, and which preventive actions that could lead to improved sleep among shift working healthcare personnel. Methods The analysis included then scientific articles (between year 2007-2013). The literature was sought from the databases Cinahl, PsykINFO och PubMed. Result The result showed that shift work that interfere with normal sleep times has an obvious harmful effect on sleep with difficulty falling asleep, and sleepiness during working time as well as leisure time. Significant was that age and low hardiness increased the risk for insomnia. To be able to take a nap during the nightshift was an important action to prevent sleepiness and promote health among shift working healthcare personnel. Conclusion Due to the fact that shift work in itself has an obvious harmful effect on sleep, it is of great importance to ensure the best possible conditions to retain health within the health care personnel in the long term. Beside planning for good shift systems, including night brake with possibility to take a nap, it is important to take age and hardiness into consideration.

No description available.