Association between engagement in COVID-19-related work and depressive symptoms among hospital workers in a designated COVID-19 hospital in Japan: a cross-sectional study

Objectives To examine whether engagement in COVID-19-related work was associated with an increased prevalence of depressive symptoms among the staff members working in a designated medical institution for COVID-19 in Tokyo, Japan. Design A cross-sectional study. Setting Data were obtained from a health survey conducted in July 2020 among the staff members of a designated medical institution for COVID-19 in Tokyo, Japan. Participants A total of 1228 hospital workers. Exposure of interest Engagement in COVID-19-related work (qualitatively (ie, the risk of SARS-CoV-2 infection at work or affiliation to related departments) as well as quantitatively (ie, working hours)) and job categories. Outcome measures Depressive symptoms. Results There was no significant association between depressive symptoms and engagement in work with potential exposure to SARS-CoV-2 or affiliation to COVID-19-related departments. However, working for longer hours in March/April, when Japan witnessed a large number of infected cases, was significantly associated with depressive symptoms (>= 11 hours/day: prevalence ratio (PR)=1.45, 95% CI=1.06 to 1.99, compared with <= 8 hours/day). Nurses were more likely to exhibit depressive symptoms than did doctors (PR=1.70, 95% CI=1.14 to 2.54). Conclusions This study suggests that the risk of SARS-CoV-2 infection at work or having an affiliation to related departments might not be linked with a higher prevalence of depressive symptoms among Japanese hospital workers; contrarily, long working hours appeared to increase the prevalence of depressive symptoms.