NOCTURNIN Gene Diurnal Variation in Healthy Volunteers and Expression Levels in Shift Workers.

OBJECTIVE: The NOCTURNIN gene links nutrient absorption and metabolism to the circadian clock. Shift workers are at a heightened risk of overweight and of developing obesity and metabolic syndrome. This study investigates the diurnal variation of NOCTURNIN in healthy volunteers and its expression levels in rotational shift and daytime workers. METHODS: NOCTURNIN expression levels were evaluated in peripheral blood lymphocytes from 15 healthy volunteers at 4-hour intervals for 24 h. Metabolic parameters and NOCTURNIN expression were measured in workers engaged in shift and daytime work. RESULTS: In the group of volunteers NOCTURNIN expression showed diurnal variation, with a peak at 8:00 AM. NOCTURNIN expression was higher in shift workers than in daytime workers. Multivariate analysis confirmed the role of shift work as an independent factor affecting NOCTURNIN expression. Notably, its level correlated directly with body mass index and inversely with total energy expenditure. CONCLUSIONS: Measuring NOCTURNIN expression levels in human peripheral blood lymphocytes can improve investigations on the relationship between changes in circadian rhythm and metabolic disorders. Shift workers show higher NOCTURNIN levels than daytime workers.

Peripheral Skin Temperature and Circadian Biological Clock in Shift Nurses after a Day off.

The circadian biological clock is essentially based on the light/dark cycle. Some people working with shift schedules cannot adjust their sleep/wake cycle to the light/dark cycle, and this may result in alterations of the circadian biological clock. This study explored the circadian biological clock of shift and daytime nurses using non-invasive methods. Peripheral skin temperature, cortisol and melatonin levels in saliva, and Per2 expression in pubic hair follicle cells were investigated for 24 h after a day off. Significant differences were observed in peripheral skin temperature and cortisol levels between shift and daytime nurses. No differences in melatonin levels were obtained. Per2 maximum values were significantly different between the two groups. Shift nurses exhibited lower circadian variations compared to daytime nurses, and this may indicate an adjustment of the circadian biological clock to continuous shift schedules. Non-invasive procedures, such as peripheral skin temperature measurement, determination of cortisol and melatonin in saliva, and analysis of clock genes in hair follicle cells, may be effective approaches to extensively study the circadian clock in shift workers.

Low perceived social support is associated with CD8+CD57+ lymphocyte expansion and increased TNF-α levels.

Social support has been supposed to have a positive impact on the function of the immune system. However, the relationship between perceived social support and immune function has not yet been fully investigated. In this cross-sectional study, we investigated the link between perceived social support and lymphocyte subpopulations and cytokines. 232 healthy subjects provided a blood sample and completed the Multidimensional Scale of Perceived Social Support (MSPSS) questionnaire. Lymphocyte immunophenotypes and cytokines were determined. Significantly increased CD8+CD57+ lymphocytes and TNF-α levels were found in group with low perceived social support. Multivariate linear regression corrected for possible confounders confirmed a significant role of perceived social support in predicting the number of CD8+CD57+ lymphocyte and TNF-α levels. This study supports the association between perceived social support and immune function. In particular, poor social support may be related to a state of chronic inflammation sustained by CD8+CD57+ lymphocyte expansion and increased TNF-α levels.

Rotating-shift nurses after a day off: peripheral clock gene expression, urinary melatonin, and serum 17-ß-estradiol levels.

OBJECTIVE: Impairment of clock gene expression and changes in melatonin and 17-ß-estradiol levels may constitute biological alterations underlying the increased risk of breast cancer among shift workers. The aim of this study was to compare levels of selected core clock gene expression, 6-sulfatoxymelatonin (aMT6s), and 17-ß-estradiol between rotational shift work (SW) and daytime (DT) workers after a day off. METHODS: The cross-sectional study comprised 60 nurses with ≥2 years of SW and 56 permanent DT nurses. Transcript levels of circadian genes BMAL1, CLOCK, NPAS2, CRY1, CRY2, PER1, PER2, PER3, and REVERBα were determined by quantitative real-time polymerase chain reaction (PCR) in lymphocytes. All participants were tested in the early follicular phase of the menstrual cycle. Samples were collected at the beginning of the morning-shift after a regular night's sleep on a day off. Chronotype and sociodemographic characteristics were also evaluated. RESULTS: We found a significantly higher expression of BMAL1, CLOCK, NPAS2, PER1, PER2, and REVERBα and a lower expression of PER3, CRY1 and CRY2 among SW compared to DT nurses. SW participants did not demonstrate a significant difference in aMT6s levels, but they did show significantly higher 17-ß-estradiol levels compared to DT nurses. Multiple linear regression analysis confirmed the role of SW on expression of BMAL1 (ß 0.21, P=0.040), CLOCK (ß 0.35, P=0.008), NPAS2 (ß 0.30, P=0.012), PER1 (ß 0.33, P=0.008), PER2 (ß 0.19, P=0.047), PER3 (ß -0.27, P=0.012), CRY1 (ß -0.33, P=0.002), CRY2 (ß -0.31, P=0.005), REVERBα (ß 0.19, P=0.045), and on 17-ß-estradiol levels (ß 0.32, P=0.003). The analysis also confirmed the role of chronotype as an independent factor for PER1 (ß 0.48, P=0.001) and PER2 (ß -0.22, P=0.022) expression, and 17-ß-estradiol levels (ß 0.26, P=0.011). CONCLUSIONS: Rotating SW nurses show alterations in peripheral clock gene expression and 17-ß-estradiol levels at the beginning of the morning shift after a day off.

[Biological risk and health care workers: analysis of the effects of work chronobiology on the immune system]. / Rischio biologico ed operatori sanitari: analisi dell'interferenza tra cronobiologia lavorativa e sistema immunitario.

BACKGROUND: Healthcare workers may be exposed to a variety of biological hazards. Although many studies have shown that some immunological alterations were related to work stress and sleep disorders, few studies investigated effects of shiftwork on the immunological system. OBJECTIVES: The aim of the study was to compare the immune status of a group of nurses on shiftwork with that of nurses working only day shifts. METHODS: A total of 138 nurses were evaluated at baseline and after a year of follow-up, via tests for perceived stress, daytime sleepiness, number of lymphocytes and subpopulation of CD3+, CD4+, CD8+-CD57+, CD19+ and CD56+, cytotoxic activity and lympho-prolferative response of NK cells, serum concentrations of IL-1beta, IL-6, INFgamma and TNFalpha. RESULTS AND CONCLUSION: No significant alterations of any of the studied parameters were found both at baseline and after a year of follow-up. The biological hazards for nurses do not seem to be increased by shiftwork.

[Shift work and cardiometabolic risk]. / Lavoro a turni e rischio cardiometabolico.

Shift work is frequently associated with coronary heart disease. Medical research indicate metabolic disturbance among shift workers, which is characterized by associated modifications in the concentration of serum glucose and serum lipids, hypertension and obesity, especially addominal weight. Atrasversal study has been carried out: 193 (126 females and 67 males) healthcare shift workers were compared with 221 (160 females and 61 males) day workers. Medical history, health examination including anthropometric and arterial blood pressure measurements were assessed. All participants were submitted a standardized questionnaire on health-related behaviours and biochemical determinations (fasting plasma glucose, HDL-cholesterol, triglycerides). Job seniority of shift work resulted at 13.5 +/- 8.2 among shift workers and 19.0 +/- 11.3 among day workers. Assessment of the metabolic syndrome relevance was defined according to the criterions proposed by the International Diabetes Federation. The 20% shift workers (33% males and 13% females) was affected by metabolic syndrome against 12% non shift workers (20% males and 9% females). The most frequently altered parameter, apart from metabolic syndrome, was high abdominal obesity, which occurred in 64% of the sample (70% shift workers vs 58% day workers). The results of multiple logistic regression attested the presence of a higher relative risk among shift workers regarding both the prevalence of a metabolic syndrome (OR 2,1 - 95% Cl 1.15-3.86) and the excess in abdominal obesity (OR 1.8 - 95% Cl 1.16-3.25). After adjusting confusing factors such as smoke, age, alchool, consumption, physical activity, scholastic degree, a OR 2.9 - 95%Cl 1,53-5.53 and a OR 1.9 - 95%.Cl 1.32-3.86 were confirmed.

[Role of waist circumference in the diagnosis of metabolic syndrome and assessment of cardiovascular risk in shift workers]. / Importanza della circonferenza vita per la diagnosi di sindrome metabolica e per la valutazione del rischio cardiovascolare nei lavoratori turnisti.

BACKGROUND: Shift work is associated with coronary heart disease (CHD). Metabolic syndrome (MS) is associated with an increased risk of cardiovascular disease (CVD). An association between shift work and MS has been reported in some studies. OBJECTIVE: The purpose of this study was to compare the criteria of the National Cholesterol Education Panel (NCEP), revised NCEP (NCPEP-R) and International Diabetes Federation (IDF) metabolic syndrome criteria for the diagnosis of MS, also to explore how metabolic risk factors for CVD differ between shift workers and day workers in a cohort of Italian workers. METHODS: The study population consisted of 552 workers (361 men, 191 women; mean age 40.4 years) and included 262 healthcare providers (130 rotating shift nurses and 132 day nurses), 204 forestry workers and 86 factory workers. Fasting blood sugar level, HDL-cholesterol, triglycerides, blood pressure, and waist circumference were measured. RESULTS: Healthcare providers had greater waist circumference (p< 0.01), serum triglycerides (p< 0.01) and fasting plasma glucose (p< 0.001) compare with the other worker categories. In comparison with day workers, rotating shift nurses had greater waist circumference (p<0.001), higher serum triglycerides (p< 0. 001) and fasting plasma glucose (p< 0.05), and lower concentrations of HDL cholesterol (p<0.01) The prevalence of MS according to NCEP criteria was 8.3%, according to NCEP-R criteria 9.3% and 12% according to IDF criteria. No significant association between MS and shift work was found. Abdominal obesity and high serum triglycerides was significantly associated with shift work after adjusting for age, sex, smoking, alcohol consumption and job seniority, with an OR of 2.74; 95% CI: 1.43-5.26 for high serum triglycerides and an OR of 1.81; 95% CI: 1.0-3.2 for abdominal obesity assessed according to IDF criteria. No significant association with NCEP and NCEP-R criteria was observed. CONCLUSIONS: The data show greater prevalence of cardiovascular risk factors among healthcare providers. Shift work was significantly associated with high triglycerides and abdominal obesity using IDF criteria. Measurement of waist circumference is a simple and non-invasive method to use in the evaluation of metabolic risk factor for CVD.

[Assessment of plasma homocysteine levels in shift healthcare workers]. / Valutazione dell'omocisteina nei lavoratori turnisti.

BACKGROUND: Previous studies have indicated an association between shift work and cardiovascular disease. Increased plasma homocysteine levels has been proposed as a cardiovascular risk factor independent of other conventional risk factors. AIMS: Our aim is to verify the usefulness of plasma homocysteine as a screening test to prevent cardiovascular diseases in shift workers. METHODS: Thirty rotating shift nurses and 28 daytime nurses have been submitted during 18 months to regular taking of arterial pressure and body weight. Venous blood was drawn to measure glycaemia, triglycerides, plasma cortisol level, HDL cholesterol, blood cell count, alanine-aminotransferase, aspartate-aminotransferasi, gamma-GT, and plasma homocysteine. RESULTS: No increase in average plasma homocysteine in rotating shift nurses, nor a higher frequency in hyperomocisteinemia than in daytime workers was found. A significant difference was observed in body weight and systolic blood pressure (p<0.05), which resulted higher in rotating shift workers than in daytime workers. A significant increase was observed in alanine-aminotransferase (ALT) among shift workers (p<0.05). CONCLUSION: Plasma homocysteine measurement should not be employed as a screening test for the prevention of cardiovascular disease in rotating shift workers.

Assessment of cardiovascular risk in shift healthcare workers.

BACKGROUND: Shift work has been associated with an increased risk of cardiovascular disease (CVD); in particular, night work affects the circadian rhythm. DESIGN AND METHODS: The study examines the effectiveness of three screening methods and plasma hyperhomocysteinemia, an independent risk factor, in assessing the risk of CVD in 147 healthcare providers doing daytime or rotational shift work. The methods applied were: (i) the method proposed by the European Cardiovascular Indicators Surveillance Set (EUROCISS); (ii) the metabolic syndrome (MS) criteria of the Third Report of the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (ATPIII) and (iii) the MS criteria of the International Diabetes Federation (IDF). RESULTS: EUROCISS was unable to distinguish between the CVD risk of daytime and rotational shift workers. Both the ATPIII and the IDF detected MS, which is strongly associated with CVD, but only the IDF evidenced a significantly greater prevalence of MS (P<0.05) among shift workers. Hyperhomocysteinemia was unable to discriminate the CVD risk between daytime and shift workers, as it was influenced by multiple confounding factors. CONCLUSIONS: The increased risk of CVD associated with shift work is related to the greater incidence of MS among these workers. In our study a high prevalence of MS was detected only with the IDF. The method is useful for CVD prevention and the promotion of health during any medical examination of shift workers.

[Hymenoptera stings in forestry department agents: evaluation of risk]. / Punture di imenotteri negli agenti del corpo forestale dello stato: valutazione del rischio.

BACKGROUND: In sensitized subjects Hymenoptera stings may provoke the awakening of mediated systemic reactions of I type IgE, which can sometimes be serious. Considering the type of work performed activity and the high frequency of reported hymenoptera sting episodes, a sample of 206 Forestry Department agents was surveyed who worked outside urban areas in the Marche Region. OBJECTIVES: The aim of the study was to analyse the prevalence of stings and their possible systemic reactions, as well as to evaluate the type of occupational risks involved. METHODS: A total of 206 agents were examined and questioned about the number of stings suffered during work and about the kind of subsequent skin and systemic reactions; they were then classified according to the method proposed by H.L. Mueller. RESULTS: 179 agents reported having suffered from hymenoptera stings and, of these, 53 subjects (29,6%) remembered that one episode at least occurred during work. Among 175 operators (98%), 4 had a regular reaction, with appearance of a generalized urticaria and uneasiness. In the remaining 4 agents (2%) there was a local extensive reaction, which was not associated with systemic reactions and they were all referred to allergological examination. 19 agents (10,6%) suffered more than 5 stings altogether, but none developed a systemic reaction. 87% of the subjects practised self-medication, 7% reported to the casualty department of the local hospital or to their own doctor, and 6% undertook no cure at all. CONCLUSIONS: Epidemiological studies agree in recognizing that, in the general population, the percentage of systemic reactions after one or more hymenoptera stings varies from 0,15% to 3,3%. In categories of workers occupationally at risk, the prevalence of systemic reactions varies from 4,5% to 26%. The prevalence of systemic reactions in Forestry Department agents was 2%, which is similar to the prevalence in the general population. Therefore, rather than occupational risk, there appeared to be a generic risk made more serious by working conditions for Forestry Department agents due to their possible exposure to hymenoptera stings. The occupational health physician needs to monitor these events, due to the fact that frequent exposure to stings, above all occurring within a short period of time (less than two months) favours an increase in the tendency to develop systemic reactions, with a more serious prognosis, especially when working in isolated conditions.

[Usefulness of a questionnaire and RAST in screening of health care workers allergic to latex]. / Utilità del questionario e del RAST nello screening di operatori sanitari allergici al lattice.

BACKGROUND: The prevalence of latex mediated IgE allergy in health care workers varies, according to the various studies, from 0.5% to 16. 7%. The onset of latex allergy involves aspects concerning the worker's health, the need for job transfer and possible retraining. In any case, the use of latex gloves in health care environments cannot be discarded, since they offer more efficacious protection from biological agents, compared to gloves of different materials. OBJECTIVES: Our objectives were to verify the prevalence of latex allergy in a sample of 515 health care workers and evaluate the usefulness of RAST and a questionnaire especially organized to identify potentially allergic subjects, at the same time limiting the number of false positive and false negative results. METHODS: 515 health care workers of the ASUR Zone7-Ancona local health unit accepted to answer to a questionnaire and to undergo a RAST testfor latex. Those with positive responses to the questionnaire or to RAST were later invited to undergo further allergological tests (prick and prick by prick). The questionnaire was revised according to the results obtained, thus increasing its positive predictiveness. RESULTS: Prevalence of latex allergy in our sample was 1, 7%, positive predictiveness of RAST was rather low (31.3%), but increased considerably if combined with the modified questionnaire (62.5%). The Prick by Prick test gave more specific results than the Prick test. CONCLUSIONS: The proposed questionnaire can reduce the number of false positive workers needing to undergo further allergological tests and may be usefully applied in the screening of latex mediated IgE allergy in health care workers.

[Guidelines for health surveillance of health care workers exposed to biological risks set up by the Italian Society for Occupational Health and Industrial Hygiene: application in health facilities of the Regional Health Administration--District No. 7, Ancona]. / Rischio biologico per i lavoratori della sanità: applicazione delle Linee Guida SIMLII nella ASUR--Zona Territoriale 7 di Ancona.

BACKGROUND: Evidence Based Medicine and the need to achieve better management of health budgets call for verification and, if necessary, revision of the criteria used in Occupational Health, in order to ensure appropriate measures as regards protection of health at the workplace. In December 2003, the Marche Region initiated a process of reform of the regional health service, which will be completed in two years, and will provide a new regional health organization that will improve the quality and appropriateness of health services available to the population. The reform also involves the Occupational Health Services responsible for prevention activities for 20,000 health care workers employed in regional public health facilities. The need was strongly felt to set up a network that would meet the health needs of health care workers, by adopting a common language among occupational health physicians, by eliminating reported criticism, which is due not only to lack of communication between different structures and profiles, but also to the different methods of approach, evaluation and management of occupational risks. OBJECTIVES AND METHODS: From a historical point of view, the health sector has the biggest as regards prevention of biological risk. Therefore, with a view to harmonizing actions and approach among occupational health physicians in the evaluation of this risk, the publication by the Italian Society for Occupational of Health and Industrial Hygiene of Guidelines for health surveillance of health care workers exposed to biological risks, produced by the working group under the leadership of Prof. Lorenzo Alessio, was considered to offer an interesting opportunity to verify the reproducibility of methods and the quality of results, as applied to health facilities under the Regional Health Administration in Ancona (District No. 7). RESULTS AND CONCLUSION: The Guidelines fully confirmed the need to plan activities, starting from analysis of epidemiological and occupational data, thus assuring good results both in terms of efficacy and efficiency of the health surveillance programme used. This method also assures a high level of appropriateness of medical measures as regards the "safety" target, at the same time avoiding waste and poor management of human and economic resources, which were till now caused by differences in methods used in assessment of biological risk.