Autonomic nervous activity changes in relation to the reporting of subjective symptoms among male workers in an information service company

Heart rate variability in occupational health --a systematic review

This systematic review evaluates and summarizes the evidence of association between work-related factors and heart rate variability (HRV) in workers. We reviewed English articles indexed in MEDLINE under the key words: work, worker, occupational, industrial, and heart rate variability. Studies were included if one or more of the dependent variables was one of the time- or frequency-domain indexes of HRV [standard deviation of all normal-to-normal (NN) intervals (SDNN), mean of the 5-min standard deviations of NN intervals calculated over several hours (SDNN index), the root mean squared differences of successive NN intervals (RMSSD), integrated spectral powers of high (HF, > 0.15 Hz) and low frequency (LF, 0.04-0.15 Hz) HRV, and the LF/HF ratio] as recommended by the European Society of Cardiology and the North American Society of Pacing Electrophysiology. Physical and chemical work environments (i.e. exposure to occupational toxicants and hazardous environments), psychosocial workload (i.e. job stressors), and working time (i.e. shift work) had been examined and identified as having associations with low HF power. These findings may indicate that research into parasympathetic nervous system activity should be focused to protect cardiovascular health at work. We also propose the use of very low and ultralow frequency HRV components in autonomic research for workers' health.

A 2-year cohort study on the impact of an Employee Assistance Programme (EAP) on depression and suicidal thoughts in male Japanese workers

OBJECTIVE

Depression and suicide-related behaviours are important issues for workers, and the number of Japanese companies contracting with the Employee Assistance Programme (EAP) to promote employees' mental health has recently increased. However, no longitudinal studies have reported that the EAP maintains or improves the overall level of depression among employees qualitatively. Thus, we attempted to assess the impact of the EAP on depression and suicide-related behaviours in the workplace.

METHODS

A cohort study was conducted on 283 male Japanese employees aged 22-38 years at a Japanese information-technology company introducing the EAP. Because the privacy policy of the EAP service made it difficult to perform a randomised design in the workplace, 22 men working at an affiliated company without the EAP were used as a reference group. All the subjects completed the 17-item Hamilton Depression Scale (HAM-D) and Job Content Questionnaire (JCQ) consisting of job demands, control, and social support before the EAP was introduced to establish a baseline and after 2 years.

RESULTS

In the EAP group, the total HAM-D scores significantly decreased after the 2-year study period (P=0.0011); the changes in the scores of the five HAM-D items (i.e., suicidal thoughts, agitation, psychomotor retardation, guilt, and depressed mood) were significant. Specifically, 19 (86%) of the 22 workers with a positive response to the suicidal thoughts item (i.e., score >or= 1) at baseline reported that they no longer had suicidal thoughts (i.e., score=0) after the 2 year study period. No significant changes were observed in the reference group. The three JCQ scores were not significantly different between the baseline and after the 2 year study period in both groups.

CONCLUSION

Although further studies are needed, EAPs may be a promising strategy for maintaining the good mental health of workers.