cohort study on risks of insomnia and occupational stress for depression in manufacturing workers

2019 Fiscal Year Final Research Report

• Project/Area Number: 15K08771
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Hygiene and public health
• Research Institution: Ichinomiya Kenshin College (2019); Nagoya University (2015-2018)
• Principal Investigator: Sakakibara Hisataka 一宮研伸大学, 看護学部, 教授 (80153873)
• Co-Investigator(Kenkyū-buntansha): 西谷 直子 名古屋大学, 医学系研究科(保健), 教授 (10587009)
• Project Period (FY): 2015-04-01 – 2020-03-31
• Keywords: 睡眠障害 / うつ病

Outline of Final Research Achievements

This 6-year cohort study (2011-2017) investigated the association between insomnia and onset of depression in male workers. Depression and insomnia were assessed using CES-D and the Athens Insomnia Scale (AIS), respectively. The analysis was made with 1,332 daytime male workers aged < 60 who had CES-D score of < 16 at baseline. Insomnia was the greatest risk for developing depression. Subjects with AIS score of 6 or more had a 4.97 times greater risk (95%CI 2.97-97-8.33). The hazard ratio (HR) increased with AIS scores at baseline; for a total AIS score of 1-3 (HR 2.14, 95%CI 1.32-3.45) and for an AIS score of 4-5 (HR 3.93 95%CI 2.40-6.42). Severer insomnia could be a greater risk for onset of depression. Improving sleep status might be a beneficial measure to reduce the risk of developing depression in male workers.

Free Research Field

産業衛生

Academic Significance and Societal Importance of the Research Achievements

本調査は、これまで調査がまれな職場労働者を対象に、睡眠障害の存在が将来のうつ症状発症のリスクを高めることを示すとともに、不眠症状の程度が強いほど将来のうつ症状発症リスクが高くなることを示した、国際的にも意義のある研究である。将来のうつ症状発症リスクは、不眠症状の程度が強いほどは高く、軽い不眠症状でもリスクが高まり、注意を要する。また、職場のうつ病対策として、労働者の不眠症状や睡眠障害にも注意を向け、その改善に努めることが、うつ病発症予防にも繋がる可能性を示唆した。