A follow-up study on the association of working conditions and lifestyles with the development of (perceived) mental symptoms in workers of a telecommunication enterprise.

AIM: This study investigated the association of working conditions and lifestyle with mental health in Japanese workers.
METHODS: A follow-up study was carried out in the Kanto district of Japan of workers in a telecommunications enterprise who received their first annual health check-up between 1992 and 1996 and were between 20 and 54 years old. Workers who reported mental symptoms, had a past history of disease, or current illness at their first check-up were excluded from the analysis. In total, the study included 23 837 workers. The association between working conditions and lifestyle and the development of mental symptoms was investigated by pooled logistic regression analyses.
RESULTS: Working long hours and part-time work, as opposed to normal daytime hours of work, were factors associated with the development of mental symptoms in males, as were smoking, short sleeping hours, little physical exercise, rarely taking three meals a day, frequently eating within 1 h before sleep, much preference for salty meals and little preference for vegetables. Consumption of alcohol was negatively associated with the development of mental symptoms in males. Overall, the results suggested that the lower the Healthy Work and Lifestyle Score, the higher the risk of developing mental symptoms.
CONCLUSIONS: Working conditions and lifestyle, especially food preferences, have an apparent influence on the mental health of Japanese workers. Moreover, the Healthy Work and Lifestyle Score indicates that working conditions and lifestyle appear to have a cumulative influence upon the mental health of Japanese workers.