Associations of testosterone and cortisol concentrations with sleep quality in Japanese male workers.

Low testosterone concentrations are associated with disrupted sleep, and high levels of cortisol, which is elevated in response to stress, lead to insomnia. This study aimed to investigate the associations of testosterone and cortisol concentrations with sleep quality and to examine potential interactions between them in Japanese working men. This study was a cross-sectional design, and testosterone and cortisol concentrations in blood were the exposure variables and sleep parameters were the outcome variables. The Japanese version of the Pittsburgh Sleep Quality Index was used to measure sleep quality, and it included the total duration of sleep, time in bed (TIB), and sleep efficacy. We included 178 men (mean age = 49.1 years, standard deviation = 9.0) who completed all components in the questionnaire related to sleep and provided blood samples. Testosterone and cortisol concentrations were negatively associated with TIB (standardized beta = -0.15 and -0.24, p < 0.05, respectively), while only testosterone concentrations were positively associated with sleep efficacy (standardized beta = 0.15, p < 0.05). An interaction effect of testosterone and cortisol was significant for TIB and sleep efficacy (standardized beta for interaction term = 0.40, p < 0.001 and -0.22, p = 0.012, respectively). When stratified by cortisol concentrations, the associations between testosterone concentrations and sleep parameters were modified. Our findings suggest that associations between testosterone concentrations and sleep parameters are stronger at low cortisol concentrations, but not at high cortisol concentrations. High cortisol concentrations may diminish associations between low testosterone concentrations and diminished sleep efficacy.

Andropause symptoms and sickness absence in Japanese male workers: a prospective study.

OBJECTIVE: The purpose of the study was to investigate the association between andropause symptoms and sickness absence in Japanese male workers over 2 years. METHODS: A baseline survey asking about andropause symptoms, along with blood sampling for testosterone level, was conducted in June 2009. A total of 418 men (mean age = 52.4 years, SD = 8.6) participated and were followed through 2011. Hazard ratios (HRs) and 95% confidence intervals (CIs) for sickness absence were calculated using Cox proportional hazard models. RESULTS: During the follow-up period, 31 of 35 participants who took sickness absences had physical illnesses. A higher andropause symptom score was associated with an increased risk of sickness absence. Testosterone deficiency (<350 ng/dL) was not associated with sickness absence. Among the subscales of andropause symptoms, the somatic symptom score was positively associated with sickness absence, whereas testosterone deficiency combined with high sexual symptoms was not associated with sickness absence. Results were similar when limited to sickness absence because of physical illness. No significant interaction between andropause symptoms and testosterone deficiency was found. CONCLUSIONS: Non-specific andropause symptoms unrelated to testosterone deficiency were positively associated with sickness absence.

Association Between Cortisol to DHEA-s Ratio and Sickness Absence in Japanese Male Workers.

PURPOSE: This study aimed to investigate the association between serum levels of cortisol and dehydroepiandrosterone sulfate (DHEA-s) and sickness absence over 2 years in Japanese male workers. METHOD: A baseline survey including questions about health behavior, along with blood sampling for cortisol and DHEA-s, was conducted in 2009. In total, 429 men (mean ± SD age, 52.9 ± 8.6 years) from whom blood samples were collected at baseline were followed until December 31, 2011. The hazard ratios (HR) and 95% confidence intervals (CI) for sickness absence were calculated using a Cox proportional hazard model, adjusted for potential confounders. RESULTS: Among 35 workers who took sickness absences, 31 had physical illness. A high cortisol to DHEA-s ratio increased the risk of sickness absence (crude HR = 2.68, 95% CI 1.12-6.41; adjusted HR = 3.33, 95% CI 1.35-8.20). The cortisol to DHEA-s ratio was linearly associated with an increased risk of sickness absence (p for trend < .050). Single effects of cortisol and DHEA-s levels were not associated with sickness absences. This trend did not change when limited to absences resulting from physical illness. CONCLUSION: Hormonal conditions related to the hypothalamus-pituitary-adrenocortical axis and adrenal function should be considered when predicting sickness absence. The cortisol to DHEA-s ratio may be more informative than single effects of cortisol and DHEA-s levels.

Confirmation of Maslow's Hypothesis of Synergy: Developing an Acceptance of Selfishness at the Workplace Scale.

This study aimed to develop a new Acceptance of Selfishness at the Workplace Scale (ASWS) and to confirm Maslow's hypothesis of synergy: if both a sense of contribution and acceptance of selfishness at the workplace are high, workers are psychologically healthy. In a cross-sectional study with employees of three Japanese companies, 656 workers answered a self-administered questionnaire on paper completely (response rate = 66.8%). Each questionnaire was submitted to us in a sealed envelope and analyzed. The ASWS indicated high internal consistency (Cronbach's alpha = 0.86). Significant (p < 0.001) positive moderate correlations between ASWS scores and job control scores support the ASWS's convergent and discriminant validity. Significant (p < 0.001) associations of ASWS scores with psychological distress and work engagement supported the ASWS's criterion validity. In short, ASWS was a psychometrically satisfactory measure. Significant (p < 0.05) interactions between a sense of contribution and acceptance of selfishness at the workplace in linear regression models showed that when those two factors are low, psychological distress becomes high. However, when a sense of contribution and acceptance of selfishness are high, work engagement also becomes high. Thus, Maslow's hypothesis of synergy was confirmed.

Moderating effects of salivary testosterone levels on associations between job demand and psychological stress response in Japanese medical workers.

Levels of job stress have been shown to be inversely associated with testosterone levels, but some inconsistent results have been documented. We investigated the moderating effects of testosterone levels on associations between job stress-factors and psychological stress responses in Japanese medical workers. The participants were 63 medical staff (20 males and 43 women; mean age: 30.6 years; SD=7.3) in Okayama, Japan. Their job-stress levels and psychological stress responses were evaluated using self-administered questionnaires, and their salivary testosterone collected. Multiple regression analyses showed that job demand was positively associated with stress responses in men and women. An interaction between testosterone and support from colleagues had a significant effect on depression and anxiety for women. In women with lower testosterone levels, a reducing effect of support from colleagues on depression and anxiety was intensified. In women with higher testosterone levels, depression and anxiety levels were identical regardless of support from colleagues. Testosterone may function as a moderator between perceived work environment and psychological stress responses for female medical workers.

Associations of workplace bullying and harassment with stress reactions: a two-year follow-up study.

The purpose of this prospective study was to investigate the effect of the patterning of workplace bullying and harassment over two time points (chronic, remission, onset, and never) on psychological and physical stress reactions. The subjects were 543 workers at welfare facilities for the elderly in Japan who completed a self-administered questionnaire at Time 1 (from August to September, 2009) and at Time 2 (from September to October, 2011). Workplace bullying and harassment were assessed using the Negative Acts Questionnaire (NAQ). Stress reactions were assessed using the Brief Job Stress Questionnaire. In the multiple logistic regression analyses, onset of person-related bullying was significantly (p<0.05) positively associated with both psychological and physical stress reactions at Time 2. Chronic form of person-related bullying was significantly (p<0.05) positively associated with psychological stress reaction at Time 2. Onset of sexual harassment was significantly (p<0.05) positively, and remission of sexual harassment was significantly (p<0.05) negatively associated with physical stress reaction at Time 2. Onset and chronic form of person-related bullying and onset of sexual harassment can cause stress reactions. Remission of sexual harassment can terminate physical stress reaction.

Modification Effects of Changes in Job Demands on Associations Between Changes in Testosterone Levels and Andropause Symptoms: 2-Year Follow-up Study in Male Middle-Aged Japanese Workers.

PURPOSE: The purpose of this longitudinal study was to ascertain if changes in job demands modify associations between changes in testosterone levels and andropause symptoms in male Japanese workers. METHOD: A baseline survey including job demands and the Aging Males' Symptoms scale, lifestyle factors, and blood levels of testosterone was conducted in 2007. Among 192 men (mean age ± SD 52.2 ± 7.6 years) who completed all relevant questionnaires and provided blood at baseline, 104 men (50.9 ± 7.2 years) were followed up in 2009. Changes of variables in 2 years were calculated (data of follow-up minus those of baseline). RESULTS: Testosterone levels were increased significantly, whereas job demands and somatic symptoms were reduced significantly, at follow-up. Changes in testosterone levels were negatively associated with changes in total andropause symptoms, psychological symptoms, and sexual symptoms (standardized ß = -0.27, -0.24, and, -0.29, p < 0.05, respectively), after adjustment for confounders. Changes in job demands were positively associated with changes in somatic symptoms (standardized ß = 0.21, p < 0.05). Significant interactions of changes in testosterone levels and job demands were noted for changes in psychological symptoms (standardized ß = 0.26, p < 0.05). For men with a 1-SD reduction in job demands, negative associations between changes in testosterone levels and psychological symptoms were intensified, but not for men with a 1-SD increase in job demands. CONCLUSION: Andropause symptoms may be affected by changes in testosterone levels and job demands. Change in job demands may modify associations between changes in testosterone levels and andropause symptoms.

Job stress and agentic-communal personality traits related to serum cortisol levels of male workers in a Japanese medium-sized company: a cross-sectional study.

BACKGROUND: Although serum cortisol is a widely accepted index of stress levels, associations between job stress and cortisol levels have been inconsistent. Individual differences in personality traits were discussed as one compelling explanation for this discrepancy. Agentic-communal personality traits have been examined as possible predictive factors for psychological stress. PURPOSE: This study investigated correlations among agentic-communal personality traits and serum cortisol levels. It was also investigated whether job stress levels modified correlations between agentic-communal personality and cortisol levels. METHODS: Participants were 198 male workers (mean age = 52.2 years) employed by a shipbuilding company in Japan. Questionnaire data and blood samples were collected during an annual health checkup. Participants completed a self-report questionnaire that included the Job Content Questionnaire (JCQ) that assesses job control as job stress levels the Communion-Agency scale (CAS) and questions regarding health behaviors. RESULTS: Communion positively correlated with serum cortisol levels and unmitigated agency negatively correlated with serum cortisol levels. Stratified by job control, communion positively correlated with serum cortisol levels and agency negatively correlated with serum cortisol levels in participants with low levels of job control. Unmitigated agency negatively correlated with serum cortisol levels in participants with high levels of job control. CONCLUSION: Levels of job control may modify correlations of gender-related personality with serum cortisol levels. Especially with exposure to high job stress, male workers with high femininity (i.e., high communion and low agency) were more likely to have a high stress response as measured by serum cortisol levels.

Reliability, validity, and significance of assessment of sense of contribution in the workplace.

The purpose of this study was to assess the validity and reliability of the Sense of Contribution Scale (SCS), a newly developed, 7-item questionnaire used to measure sense of contribution in the workplace. Workers at 272 organizations answered questionnaires that included the SCS. Because of non-participation or missing data, the number of subjects included in the analyses for internal consistency and validity varied from 1,675 to 2,462 (response rates 54.6%-80.2%). Fifty-four workers were included in the analysis of test-retest reliability (response rate, 77.1%). The SCS showed high internal consistency (Cronbach's α coefficients in men and women were 0.85 and 0.86, respectively) and test-retest reliability (intraclass correlation coefficient = 0.91). Significant (p < 0.001), positive, moderate correlations were found between the SCS score and scores for organization-based self-esteem and work engagement in both genders, which support the SCS's convergent and discriminant validity. The criterion validity of the SCS was supported by the finding that in both genders, the SCS scores were significantly (p < 0.05) and inversely associated with psychological distress and sleep disturbance in crude and in multivariable analyses that adjusted for demographics, organization-based self-esteem, work engagement, effort-reward ratio, workplace bullying, and procedural and interactional justice. The SCS is a psychometrically satisfactory measure of sense of contribution in the workplace. The SCS provides a new and useful instrument to measure sense of contribution, which is independently associated with mental health in workers, for studies in organizational science, occupational health psychology and occupational medicine.

Associations of workplace bullying and harassment with pain.

The aim of this study was to investigate associations of workplace bullying and harassment with headache, stiffness of the neck or shoulders, lumbago, and pain of two or more joints. The subjects in this cross-sectional study were recruited from workers (n = 1,913) at 35 healthcare or welfare facilities in Japan. Because of non-participation or missing data, the number of subjects included in the analysis varied (response rate ≥ 77.1%). Workplace bullying and harassment were assessed using the Negative Acts Questionnaire. Depression was assessed using the Brief Job Stress Questionnaire. The frequency of pain experienced by workers in the previous month was evaluated using a four-point scale. Many of the associations of person-related bullying, work-related bullying, and sexual harassment with headache, stiffness of the neck or shoulders, lumbago, and pain of two or more joints were positive and significant (p < 0.05). Even after adjustment for depression, some of the associations remained significant (p < 0.05). For example, changes in the prevalence ratio for headache associated with a 1-point increase in the work-related bullying score were 1.05 (95% confidence interval (CI) 1.01 to 1.09) in men and 1.03 (95% CI 1.01 to 1.05) in women after adjustment for age, marital status, employment status, work shift, and depression.

Effects of a stress management program for hospital staffs on their coping strategies and interpersonal behaviors.

The present study examined effects of a 3-h stress management program for Japanese hospital staffs that included relaxation and assertion training. Twenty-seven hospital staffs (mean age: 29.4 yr) in a stress management group and 28 hospital staffs (mean age: 29.5 yr) in a wait-list group answered evaluation surveys at both pre- and post-intervention. Self-administered questionnaires including items on job stress, coping strategies, and interpersonal behaviors were evaluated. The stress management program was given six different participant groups: 3 groups were the stress management group and 3 groups were the wait-list group. The program increased active coping and decreased dependent behavior scores significantly in the stress management group, while decreasing assertive behavior scores in the wait-list group. A comparison of the education sub-groups showed that the first group had significantly increased assertiveness and decreased dependency scores. The second group had significantly decreased depression-anxiety scores. The data analyzed for men and women separately showed the stress management intervention significantly improved active coping and assertive behavior in men and dependent behavior in women. A brief one-time stress management program can be effective in improving active coping and assertive behaviors as well as reducing dependent behavior in hospital staffs. Sex differences were noteworthy.

Job demands as a potential modifier of the association between testosterone deficiency and andropause symptoms in Japanese middle-aged workers: a cross-sectional study.

OBJECTIVE: The present study investigated whether job demands modify the association between low levels of testosterone and andropause symptoms. STUDY DESIGN: Participants were Japanese middle-aged workers in a middle-size company. Blood samples were drawn to determine serum levels of testosterone. Participants completed a self-report questionnaire that included 5 items from the Job Content Questionnaire (JCQ) that assesses job demands, the Aging Males' Symptoms (AMS) scale as well as questions regarding health behaviors and history of disease. Analysis of data was limited to the 183 men who completed all components of the questionnaire and provided blood samples (mean age=51.9 years, SD=7.7, age range 34-67 years). MAIN OUTCOME MEASURES: The AMS which comprises three symptom sub-scales: somatic, psychological, and sexual. RESULTS: Men with low testosterone levels (<349 ng/dL) had more psychological andropause symptoms than those with high levels. In men with high psychological job demands, compared to men with low job demands, testosterone levels were positively associated with the total score for andropause symptoms and scores for somatic and psychological symptoms. CONCLUSIONS: Level of job demands may intensify the effect of testosterone deficiency on andropause symptoms.

Effects of lavender aroma on sleep quality in healthy Japanese students.

This single-blind randomized study investigated the effectiveness of lavender aroma on quality of sleep in healthy Japanese students. The data of seven participants (2 men, 5 women) in the intervention group and eight participants (3 men, 5 women) in the control group were analyzed (M age = 19.0 yr., SD = 0.9). The total procedure comprised 3 days for pre-intervention assessment, 5 days for the intervention, and 3 days for post-intervention assessment. Lavender exposure was compared with the absence of lavender (control). Information regarding the relaxing effect of aromas was provided to examine expectancy effects. Results showed that lavender aroma improved sleepiness at awakening after the intervention. Sex differences and daily variation in quality of sleep during the intervention period were not observed. The findings suggest that nighttime exposure to lavender aroma relieves sleepiness at awakening.

[Associations between workplace bullying, harassment, and stress reactions of professional caregivers at welfare facilities for the elderly in Japan].

OBJECTIVE: The purpose of this study was to describe workplace bullying experienced by professional caregivers at welfare facilities for the elderly in Japan and to confirm its effects on stress reactions. METHODS: A cross-sectional survey was carried out using self-administered questionnaires in 2009 of all the employees working in rural area of facilities for long-term care. Among the 1,233 respondents who filled out all questionnaires concerning stress reactions the Japanese version of the Negative Acts Questionnaire (NAQ) (response rate: 63.9%), we analyzed 897 professional caregivers. We measured stress reactions by using the stress reaction scores of the Brief Job Stress Questionnaire (29 items) and workplace bullying and harassment by using NAQ. We used the unpaired t-test and analysis of covariance (ANCOVA) to compare crude and adjusted average stress reactions with groups classified on the basis of each subscale of the NAQ or all of them. RESULTS: About 40% of both men and women suffered from "malicious gossip" and over 60% of both men and women experienced "someone withholding necessary information so that their work gets complicated". Among women, scores of the lack of vigor and fatigue were significantly higher in caregivers targeted by person-related bullying than those not targeted (p<0.05). Scores of depression were significantly higher in caregivers targeted by work-related bullying than those not targeted (p<0.05). Scores of anxiety were significantly higher among caregivers targeted by sexual harassment than those not targeted (p<0.05). Among men, scores of the lack of vigor were significantly lower in caregivers targeted by work-related bullying than those not targeted (p<0.05). CONCLUSIONS: Among women, workplace bullying or harassment could may aggravate effects on psychological stress responses. While among men, work-related bullying was positively associated with vigor.

Workplace bullying could play important roles in the relationships between job strain and symptoms of depression and sleep disturbance.

OBJECTIVE: The purpose of this study was to assess whether workplace bullying mediates between job strain, evaluated by the job demand-control model, and symptoms of depression and sleep disturbance. METHODS: The subjects in this cross-sectional study were recruited from all the workers (N=2,634) at 50 organizations in Japan. Due to missing data, the numbers of subjects included in the analyses varied from 1,646 to 2,062 (response rates varied from 62.5% to 78.2%). Job strain and workplace social support, workplace bullying, depression, and sleep disturbance were assessed using the Japanese versions of the Job Content Questionnaire, the Negative Acts Questionnaire, the Center for Epidemiologic Studies Depression Scale, and the Pittsburgh Sleep Quality Index, respectively. Mediation analysis followed the approach outlined by Baron and Kenny. We quantitatively estimated the mediation effects and tested their significance after adjustment for various combinations of demographic variables and workplace social support. RESULTS: Total effects of job strain index on depression or sleep disturbance were all positive and significant (p<0.05) in both genders. Mediation effects of workplace bullying were also all positive and significant (p<0.05) in both genders. Even after adjustment for workplace social support, the mediation effects were decreased, especially in women, but remained significant (p<0.05). CONCLUSIONS: Workplace bullying seems to play important roles in the relationships of job strain with depression or sleep disturbance in both genders.

Assessment of workplace bullying and harassment: reliability and validity of a Japanese version of the negative acts questionnaire.

OBJECTIVES: Interest in workplace bullying and harassment has been increasing in Japan. At present, the Negative Acts Questionnaire (NAQ) is one of the most frequently used questionnaires for assessing these issues. The purpose of this study was to develop a Japanese version of the NAQ. METHODS: We translated the original version of the NAQ using a back-translation method. Participants in this study were recruited from 737 workers at a manufacturing company in Japan. Data were obtained from questionnaires completed by 517 respondents (response rate: 70.1%). RESULTS: We used a cross-validation approach. A three-factor model was obtained from exploratory factor analyses. The confirmatory factor analysis for this model revealed values of 0.94, 0.91, 0.95, and 0.054 for the goodness-of-fit index, the adjusted goodness-of-fit index, the comparative fit index, and the root mean square error of approximation, respectively. Pearson's correlation coefficients for the NAQ scores with the Job Content Questionnaire (JCQ) support scores and the Effort-Reward Imbalance Questionnaire scores for respect and job security were significant (p<0.001) and the direction of these associations were consistent with our expectations, with the exceptions of the correlations between the NAQ sexual harassment score and the JCQ support scores. Cronbach's alpha coefficients for the scores on the entire NAQ scale and on three subscales (person-related bullying, work-related bullying, and sexual harassment) were 0.90, 0.84, 0.60, and 0.60, respectively. CONCLUSIONS: A Japanese version of the NAQ was developed and it appears to have acceptable levels of internal consistency reliability and factor- and construct-validity.

Evaluation of an internet-based self-help program for better quality of sleep among Japanese workers: a randomized controlled trial.

The effectiveness of Internet-based self-help programs for insomnia is still unclear. A randomized controlled trial was conducted to evaluate the effect of an Internet-based self-help program for better quality of sleep among adult workers. Forty-three volunteers were recruited and randomly assigned to either an intervention group (n=21) or a waiting-list group (n=22). The intervention group participated in a two-week Internet-based program, including selecting and daily practicing sleep-related target behaviors and monitoring those behaviors along with sleep quality. At the same time, each participant received automatically generated, personalized messages and reports both daily and weekly. A total of 12 intervention group participants and 18 waiting-list group participants completed questionnaires at baseline, post-intervention, and at a 3-wk follow-up. Subjective sleep quality was measured by a self-reported questionnaire developed for this study. The sleep quality score increased in the intervention group at post-intervention, with a significant interaction effect [F(1,28)=5.19, p=0.031]. Sleep-related behaviors also greatly increased in the intervention group at post-intervention, with a significant interaction effect [F(1,28)=7.14, p=0.012]. Sleep-onset latency reduced in the intervention group at follow-up, with a marginally significant effect [F(1,28)=3.52, p=0.071]. The Internet-based self-help program improves subjective sleep quality and sleep-onset latency among adult workers.

The immediate effects of 10-minute relaxation training on salivary immunoglobulin A (s-IgA) and mood state for Japanese female medical co-workers.

This study examined the effects of relaxation training on salivary IgA (s-IgA) and mood state in Japanese female medical workers. Participants were enrolled and assigned to relaxation or control groups. The relaxation group Japanese female medical workers (n = 38, mean age = 33.5 years, SD = 9.6) participated in a lecture on stress for 1 h and had 10 min of relaxation training. The control group (n = 41, mean age = 35.0 years, SD = 8.6) participated in only the lecture. S-IgA was measured, and a self-report mood questionnaire administered before the lecture and then again after the relaxation training for the relaxation group. The control group was measured before and after the lecture. The results showed that s-IgA levels significantly increased after relaxation training in the relaxation group compared with the control group (p = 0.03). A marginally significant intervention effect was observed for mood state (p = 0.06) ; indicating that the relaxation group was more likely to reduce any fatigue and confusion than was the control group. These findings suggest that short-time relaxation training is effective in relaxing mood and causes changes in immunological function.

Effects of alcohol-related health education on alcohol and drinking behavior awareness among Japanese junior college students: a randomized controlled trial.

We conducted a randomized controlled trial involving Japanese junior college students aimed at investigating the effects of a single session of alcohol health education concerning the effects of alcohol, alcohol-related health problems, and drinking behavior. Students were randomly assigned to an intervention (n=38) or a control group (n=33). The intervention group attended a 90-minute alcohol health education session that included demonstration of an ethanol patch test, watching videos, and a lecture by an ex-alcoholic. The control group received health education regarding smoking. The students. knowledge regarding alcohol, their drinking behavior, and problem drinking (CAGE) were measured by a self-administered questionnaire at the baseline and at a two-month follow-up. A repeated measures of analysis of variance (ANOVA) of those who completed the follow-up indicated the education sessions. significant intervention (group*time) effect on the scores related to knowledge of alcohol-related health problems (p=0.035), with a greater increase in the scores of the intervention group at the follow-up. No significant intervention eff ect was observed regarding drinking behavior or problem drinking as measured by CAGE (p>0.05). Alcohol-related education can be considered an effective way to increase awareness of alcohol-related health problems, but less effective for changing drinking the behavior of Japanese junior college students.