Cross-sectional Study of Depressive Symptoms and Related Factors among Workers Employed by Japanese Eldercare Institutions

Aims: This study aimed to examine the prevalence of depressive symptoms and related factors (sociodemographic characteristics and occupational variables) among workers employed by Japanese eldercare institutions (Study I). In addition, the associations between depression symptoms and job stress based on the Demand–Control–Support model were examined (Study II). Methods: Eldercare institutions in Akita prefecture were randomly selected to participate in the survey. In total, 197 institutions agreed to participate in the study, and the participants were invited to complete the survey. Of the 2,727 workers who were invited to participate, 2,404 returned complete questionnaires. Depression-symptom prevalence and severity were evaluated using the Center for Epidemiologic Studies Depression (CES-D) scale (high score, 16). Job stress was assessed using the Job Content Questionnaire (JCQ) based on the job Demand–Control–Support model. Results: (Study I) Data from 2,088 employees showed that 44.3% of them had high CES-D scores. The sociodemographic characteristics and occupational factors that were associated with a high risk of depression included young age, a short sleep duration on weeknights, and working for more than 45 h per week. (Study II) In total, 1,740 valid responses were obtained from 434 males and 1,306 females. Approximately 44.9% of the responders had high CES-D scores. Workers with long working hours had high and low scores on psychological job demand and social support, respectively. Those who exhibited high CES-D scores had significantly higher psychological job demand scores and lower decision latitude and social support scores. A positive correlation was found between psychological job demand and CES-D scores. In contrast, a negative correlation was found between decision latitude and CES-D scores and between the social support scores and CES-D scores. Conclusions: To prevent depression, employers and employees at eldercare institutions should be aware of the effects of long working hours and lack of sleep. In addition, special attention should be paid to young workers as a high-risk group, as well as to workers with substantial psychological job demands, low decision latitude, and low social support, as these workers also constitute a high-risk group.