[Association between social jetlag and presenteeism in Japanese industry: A cross-sectional study].

OBJECTIVES: Research suggests that misalignment of the biological clock and social time, referred to as social jetlag (SJL), can induce physical and mental disorders. SJL may also be associated with presenteeism (i.e., a state in which workers are unable to perform sufficiently due to mental and physical health problems, even though they are going to work). However, the association between SJL and presenteeism among workers in Japan remains unclear. This study aimed to verify the following hypotheses in a sample of workers in an industrial setting in Japan: "Workers exhibiting SJL have a high degree of work functioning impairment due to presenteeism" and "An association between SJL and presenteeism exists, even when taking work style and sleep-related factor into consideration." METHODS: A self-administered questionnaire survey was conducted with 1,573 workers in the manufacturing industry. Of these, 1,501 participants responded (response rate: 95.4%). Individuals who provided invalid answers or used alarm clocks to wake on work-free days were excluded, according to the Munich Chronotype Questionnaire (MCTQ) guidelines. The final sample comprised 980 participants (80.7% male; average age: 44.4 [SD 11.3] years). SJL was assessed using the MCTQ. Presenteeism was measured using the work functioning impairment scale. Using presenteeism as the dependent variable, we conducted hierarchical multiple regression analyses to compare the explanatory power of the different models. Independent variables were SJL, daily rest period between workdays, weekday sleep duration, and subjective insomnia. Models 2 and 3 were adjusted for age, sex, employment position, occupation, employment status, and working regulations. RESULTS: Multiple regression analyses indicated that SJL was significantly and individually associated with presenteeism (ß = .066, p = .038). After adjusting for work- and sleep-related variables (Models 2 and 3), SJL no longer contributed significantly to presenteeism. In the final model, daily rest periods (ß = .076, p = .017) and subjective insomnia (ß = .470, p < .001) remained significantly associated with presenteeism (adjusted R2 = .239). CONCLUSIONS: The hypothesis "Workers experiencing SJL have a high degree of work functioning impairment due to presenteeism" was supported in our univariate analysis. However, after considering the influence of subjective insomnia and daily rest periods, the association disappeared. Therefore, a direct relationship between SJL and presenteeism is not supported. Thus, the risk of presenteeism should be considered in two stages, first confirming the perception of insomnia among workers who experience SJL, and then considering the possibility of presenteeism occurring.

Effects of Psychological and Physical Stress on Oxidative Stress, Serotonin, and Fatigue in Young Females Induced by Objective Structured Clinical Examination: Pilot Study of u-8-OHdG, u-5HT, and s-HHV-6.

BACKGROUND: To establish a method to prevent and manage fatigue caused by psychological and physical stress in young females, early detection factors, such as understanding of fatigue and causes of psychological and physical stress, as well as a review of early management of psychiatric disease, are important. With increasing knowledge regarding the diverse causes of stress, it is important to select biomarkers with consideration of the types of stress burden and mechanisms underlying the development of physical symptoms. The methods used to search for stress characteristics is an issue that needs to be addressed. However, consensus regarding objective assessment methods for impaired mental health is lacking. METHODS: We examined the effects of an objective structured clinical examination (OSCE), considered to be a uniform source of psychological and physical stress, on biomarkers of oxidative stress and fatigue in 16 third-year female medical university students (21.3 ± 2.1 years old) in Japan with a normal menstrual cycle. A self-administered questionnaire consisting of Zung's Self-rating Depression Scale (SDS) and State-Trait Anxiety Inventory (STAI) was used to assess subjective stress. Furthermore, stress-related biomarkers (urinary 8-hydroxy-2'-deoxyguanosine [u-8-OHdG], urinary 5-hydroxytryptamine [u-5-HT], and salivary human herpesvirus-6 [s-HHV-6]) were examined at 1 month, 1 week, and 1 day before, and 1 week after the OSCE. RESULTS: The results indicated that the OSCE did not have effects on u-8-OHdG, a biomarker of oxidative stress. However, u-5-HT and s-HHV-6 were found to be elevated in examinations performed prior to the OSCE. CONCLUSIONS: The present findings suggest that u-5-HT and s-HHV-6 levels can be used for objective assessment of mental and physical fatigue in young females, including that produced not only by knowledge regarding an upcoming OSCE, but also by skill and attitude aspects related to that examination.

Omega-3 Eicosapentaenoic Acid Is Related to Happiness and a Sense of Fulfillment-A Study among Female Nursing Workers.

Background: Omega (ω) 3 fatty acid (FA) is a polyunsaturated FA (PUFA) that can modulate some mental statuses. However, most studies have not considered the functional differences between eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). We investigated associations among happiness, a sense of fulfillment and serum ω3 PUFA levels. Methods: Participants were 133 female staff from a hospital and nursing homes. Happiness was measured using the Japanese version of the subjective happiness scale (SHS); a sense of fulfillment was assessed using a visual analogue scale. Serum FA concentrations were measured. A partial correlation test and a regression model were applied. Results: The SHS scores showed significantly positive correlations with a sense of fulfillment, DHA% and EPA% (p < 0.05, < 0.05 and < 0.005, respectively), after controlling for age, BMI, menopause, snacking habits and leisure-time physical activities. A sense of fulfillment was significantly negatively correlated with α-linoleic acid%, and positively correlated with DHA% and EPA% (p < 0.05, < 0.05 and < 0.005, respectively), after controlling for the confounders. A regression model showed that a sense of fulfillment, EPA, and not stopping menstruation explained happiness (standardised beta, B = 0.18, p < 0.05; B = 0.24, p < 0.01; and B = 0.32, and p < 0.05, respectively), whereas age, BMI and snacking habits could not. Simultaneously, a regression model could not explain the association between DHA and happiness. Conclusion: Happiness was related with serum EPA%, a sense of fulfillment, and premenopause.

Serum IL-6 levels and oxidation rate of LDL cholesterol were related to depressive symptoms independent of omega-3 fatty acids among female hospital and nursing home workers in Japan.

BACKGROUND: Chronic low-grade inflammation and oxidative stress are commonly observed in persons with depression or depressive symptoms. We explored the degree of depressive symptoms under psychological stress in relation to serum LDL oxidation, inflammatory markers, and fatty acid (FA) distribution among female population. The purpose of this study was to identify peripheral factors that are related to depressive symptoms, and to assess how each factor is related to depressive symptoms. METHODS: 133 female workers in a hospital and nursing homes were recruited in Japan. Depressive symptoms were assessed using the Japanese version of the Centre for Epidemiologic Studies Depression Scale (CES-D), and perceived stress was assessed using the visual analogue scale. Cytokine levels and oxidation rate of LDL cholesterol (ox-LDL/LDL) were measured as indices of inflammation and oxidation. Omega-3 FA distribution was also measured. Path analysis and hierarchical regression analysis were used to determine if each factor was predictive of depressive symptoms. RESULTS: It was identified that serum ox-LDL/LDL was positively connected with depressive symptoms, but was more strongly related to perceived psychological stress. Elevated serum IL-6 was positively correlated with depressive symptoms, though the effect was partly transmitted via ox-LDL/LDL. Additionally, serum ω3 PUFAs were inversely associated with depressive symptoms independently of IL-6 or ox-LDL/LDL. CONCLUSION: Although this study is unlikely to fully explain the causes of depressive symptoms, it suggests that psychological stress and somatic factors such as inflammation, oxidation and nutrition are related to depressive symptoms. These findings suggest the therapeutic potential of lifestyle targets to alleviate the identified depression risk factors, anti-oxidative therapies, anti-inflammatory therapies and nutritional interventions to prevent depression.

Structural conceptualization of learning experiences in nursing master's degree programs utilized in occupational health nursing activities.

OBJECTIVES: In this study, concepts were constructed that express learning experiences in nursing master's degree programs utilized in occupational health nursing activities with the aim of clarifying those characteristics. This was based on the idea that elucidation of the characteristics of learning experiences in nursing master's degree programs used in occupational health nursing activities would be meaningful in providing high-quality occupational health services that respond to the needs of society. METHODS: Semi-structured interviews were conducted with 10 people who fulfilled the three conditions of having completed a master's degree programs, working as an occupational health nurse after completion of the program, and not continuing on to a doctoral program. The nursing conceptualization method of Naomi Funashima was used. RESULTS: From the obtained data, 512 code items expressing learning experiences in master's degree programs utilized in occupational health nursing activities were identified. These items included five core categories (concepts), 34 categories, and 69 subcategories. The five concepts constructed were "Pursuit of expertise and self-evaluation," "Mutual understanding of various people that leads to human resources utilization," "Theoretical and academic learning that influences changes in activities," "Research learning that lead to activities based on scientific evidence," and "Learning that leads to high-quality activities making use of expertise." CONCLUSIONS: It was found that various learning experiences in the master's program to pursue the specialty of occupational health nurses in order to recognize their roles as well as the experiences to take the initiative in learning had been integrated in their activities after completion of the course and had contributed to their high-quality occupational health nursing activities. It was suggested that the learning experiences in the master's program, which had been revealed in this study, were the experiences necessary for providing high-quality occupational health nursing activities to satisfy the social needs.

Class Average Score for Teacher Support and Relief of Depression in Adolescents: A Population Study in Japan.

BACKGROUND: Factors contributing to the relief of depression among adolescents have not been sufficiently revealed. The aim of this study was to assess the effect of teacher support on depression in adolescent students. METHODS: We conducted a self-rating questionnaire survey among 2862 junior high school students and 93 homeroom teachers in Japan. We employed binary logistic regression models, with teacher support averaged for each class as an explanatory variable and depression as an objective variable. To examine the interaction terms of class average score for teacher support by economic status, by student sex, and by grade satisfaction were estimated. RESULTS: Higher class average scores for teacher support were independently associated with lower levels of depression among adolescents (odds ratio [OR], 0.739; 95% confidence interval [CI], 0.575-0.948). Furthermore, the interaction of class average scores for teacher support with grade satisfaction was significant (p = .025). The interaction of class average score for teacher support with economic status and with student sex was not significant. CONCLUSIONS: Our findings suggest that higher class average scores for teacher support were significantly associated with lower depression. These results can help homeroom teachers enhance interventions and promote the health of their homeroom students.

Depressive symptoms of female nursing staff working in stressful environments and their association with serum creatine kinase and lactate dehydrogenase - a preliminary study.

BACKGROUND: The activity of creatine kinase (CK) in serum has recently been reported to be potentially associated with several types of depression. The aim of this study is to evaluate whether serum enzymes, including CK, vary even in a healthy population with depressive symptoms caused by work-related stress. We gave questionnaires and blood examinations to 93 healthy female nursing home workers and did an enzyme-linked immunosorbent assay for the quantitative detection of CK isozyme muscle-type M chain (CK-MM) in serum. FINDINGS: Depressive symptoms were determined using the Center for Epidemiologic Studies Depression (CES-D) scale and compared with the results of the blood examination and serum CK-MM levels. The CES-D results showed significant negative correlations with total CK and lactate dehydrogenase (LDH) activities and CK-MM level (r = -0.29, p = 0.0062; r = -0.29, p = 0.0065; r = -0.33, p = 0.0016, respectively). CONCLUSIONS: Total CK and LDH activities and serum CK-MM level appear to be associated with the depressive symptoms of healthy nurses working in stressful environments, although the significance level was relatively low. The simultaneous detection of serum CK and LDH activities or serum CK-MM level and LDH activity may be useful as an indicator of depressive symptoms, at least for female nursing staff with work-related stress.

Val1483Ile polymorphism in the fatty acid synthase gene was associated with depressive symptoms under the influence of psychological stress.

BACKGROUND: To study the association between lipid-metabolism and depressive symptoms, genetic polymorphisms in serotonin transporter linked promoter region (5-HTTLPR) and fatty acid synthase gene (FASN) were investigated. METHOD: A cross-sectional study was conducted on 177 women (n = 166) and men (n = 15) recruited from workers in a hospital and nursing homes in Japan. Depressive symptoms were assessed by the Center for Epidemiologic Studies Depression (CES-D) scale and perceived psychological stress was measured using visual analogue scale (VAS). The genotypes of 5-HTTLPR (insertion/deletion; L/S), and FASN (Val1483Ile) were determined by the PCR methods. Linear regression analysis was performed, in which CES-D scores served as a dependent variable, and VAS scores, gene polymorphism, and confounders as independent variables. RESULTS: Under the influence of perceived stress, S/S carriers of the 5-HTTLPR gene showed significantly higher CES-D scores in comparison with L/L+L/S carriers (F = 8.2, standardised ß = 0.15, p < 0.05). Regression analysis also confirmed that CES-D scores in participants with Ile/Ile+Val/Ile genotypes of the FASN gene were significantly higher than those with Val/Val genotype (F = 8.4, standardised ß = 0.16, p<0.05). In relation to physical features, BMI among participants with S/S genotype of 5-HTTLPR was significantly lower compared with those with L/L+L/S genotypes. CONCLUSIONS: The Val1483Ile polymorphism in the FASN was associated with depressive symptoms under the influence of psychological stress. The S variant of 5-HTTLPR was related with less obese.

Physical and psychological effects of 6-week tactile massage on elderly patients with severe dementia.

Tactile massage is a soft massage that improves physical relaxation and psychological well-being. The purpose of this study was to clarify the effects of a 6-week tactile massage on changes in physical and mental function, symptoms of behavioral and psychological symptoms of dementia (BPSD) among elderly patients with dementia. In addition, chromogranin A (CgA) levels as an index of stress examined the effects of tactile massage intervention. A tactile massage group consisting of elderly patients with dementia received tactile massage therapy a total of 30 times each for about 20 minutes between 16:00 and 17:00 hours. In the control group, the mean scores for ''intellectual'' and ''emotional function'' score decreased significantly after 6 weeks (P < .05); however, no change was observed in the tactile massage group. Both the ''aggressiveness'' score (P < .05) and CgA levels decreased significantly after 6 weeks in the tactile massage group. These results suggest that tactile massage reduces aggressiveness and stress level in patients with dementia.

The effect of short-time active listening training.

OBJECTIVES: We conducted mental health training incorporating active listening for managers at a site of a general chemical company with 1,400 employees. Our purpose was to clarify the effect of active listening training of 2.5h. METHODS: All subjects were managers. The mental health training was given to 229 managers, 21 times from May 2007 until March 2008. Surveys were conducted from May 2007 to September 2008. The training sessions were conducted in a company meeting room, starting at 2:00 p.m. The importance and significance of listening as a mental health measure and methods of active listening were explained in the training. Afterward, role-playing and follow-up discussions were done twice each. In summaries, participants wrote down what they noticed about listening and gave group presentations. The instructor commented on the presentations, and ended the session by passing out and explaining a paper summarizing what is important in listening. The training was evaluated with a questionnaire distributed at the completion of training, and questionnaires on implementation of what was learned were distributed 1, 3, and 6 mo later. The Active Listening Attitude Scale (ALAS; composed of two scales for method of listening and listening attitude) developed by Mishima et al. was also used before and 1, 3, and 6 mo after the training. RESULTS AND CONCLUSIONS: In questionnaires distributed on the same day after training, 60% of the 212 respondents said the training time was just right, and 30.1% felt it was too short. The difficulty level of the training was considered appropriate by 77.8%, and 79.7% intended to implement what they had learned. Overall satisfaction was high at 85.9%. In the questionnaire 6 mo after training, 81.4% of the 145 respondents remembered the content of the training and 49.7% said they were practicing what they had learned. They responded that their conversations with subordinates about non-work topics had increased, and communication and support at work had become smoother. ALAS was administered 4 times, from before training to 6 mo afterward, and analysis was conducted for 84 respondents. No significant difference was seen in attitude to listening, but the score increased compared with before the training. The score for method of listening increased significantly. The same results were seen when the analysis was expanded to 125 respondents before and 6 mo after the training. These results are similar to those reported previously for ALAS. The findings suggest that even short listening training of 2 h and 30 min has a positive lasting effect.

Possible connections among job stress, depressive symptoms, lipid modulation and antioxidants.

BACKGROUND: Oxidative/antioxidative status may be related to psychological stress or pathogenesis of depression. SUBJECTS AND METHODS: Participants were selected from 381 female nurses working in a university hospital, and the Brief Job Stress Questionnaire was utilized to assess them. Nurses with high job stress (JS) (n = 18) and with low JS (n = 15) consented to participate in this study. Depressive symptoms were assessed by the Centre for Epidemiologic Studies Depression scale (CES-D). Cholesterols, lipid peroxidation (malondialdehyde, MDA) and antioxidants in the plasma were measured. RESULTS: High JS participants exhibited significantly higher CES-D scores (t = 3.34, p < 0.005), and significantly lower concentrations of total cholesterol (TC), low density+very low density lipoprotein cholesterols (LDL+VLDL), alpha-tocopherol, and beta-carotene compared with low JS participants (t = 2.69, p < 0.05; t = 3.46, p < 0.005; t = 2.96, p < 0.05; t = 2.98, p < 0.05, respectively). However, the reductions in plasma indicators were substantially weakened after controlling for lifestyle factors with the exception of LDL+VLDL and alpha-tocopherol. In addition, the significance of alpha-tocopherol concentrations appeared to depend on cholesterol levels. CES-D scores correlated positively with plasma MDA levels, the MDA/TC ratio and the MDA/LDL+VLDL ratio among the low JS group (r = 0.69, p < 0.001; r = 0.79, p < 0.001; r = 0.75, p < 0.005, respectively), whereas there were no correlations among the high JS group. After controlling for lifestyle covariates, the relationship between CES-D scores and the MDA/LDL+VLDL ratio remained significant (beta = 0.95, p < 0.05) using a multiple linear regression model (F = 3.61, p < 0.05). LIMITATIONS: Sample numbers in each JS group were relatively small. CONCLUSIONS: Psychological stress may reduce the plasma levels of LDL+VLDL accompanying an alpha-tocopherol decrease. There appeared to be a correlation between elevated MDA and depressive symptoms in low JS participants.

Associations of length of employment and working conditions with neck, shoulder and arm pain among nursery school teachers.

A cross-sectional questionnaire study was carried out on nursery school (NS) teachers in public nursery schools in N city in Japan to determine the magnitude of associations of probable risk factors with neck, shoulder, and arm pain, adjusting for potential confounders in logistic regression models. Of 1438 subjects, responded to the questionnaire, 959 NS teachers in charge of a separate or mixed group of children were subjected to analyses. Prevalence of neck and/or shoulder pain was 33.6%-35.4% in NS teachers in charge of children aged 0, 0-1, 4, and 5 in contrast to 25.0-29.8% in those in charge of children aged 1,2, and 3. The prevalence of neck/shoulder pain tended to increase with the length of employment in all groups classified according to the age of children under care. In a logistic regression model that simultaneously adjusted demographic and personal variables, length of employment and care for children aged 0 in the workplace were found significantly associated with musculoskeletal pain. In further logistic models, pain in the neck/shoulders and arms had associations with some specific variables: care for children aged 0, holding/lifting a child/material, overwork, and poorly supported job situations. The odds ratios for those variables varied from 1.37 to 2.41. This results suggest that pain in the neck/shoulders and arms is induced by a wide variety of risk factors in NS teachers that include high physical workload, long working hours, job demand-support imbalance, and cumulative influence of workloads.