Cross-sectional Internet-based survey of Japanese permanent daytime workers' sleep and daily rest periods

• Published in: Journal of Occupational Health Vol. 60; no. 3; pp. 229 - 235
• Main Authors: Ikeda, Hiroki, Kubo, Tomohide, Sasaki, Takeshi, Liu, Xinxin, Matsuo, Tomoaki, So, Rina, Matsumoto, Shun, Yamauchi, Takashi, Takahashi, Masaya
• Format: Journal Article
• Language: English
• Published: Australia JAPAN SOCIETY FOR OCCUPATIONAL HEALTH 01-05-2018; John Wiley & Sons, Inc; Japan Society for Occupational Health
• Subjects: Adult; Cross-Sectional Studies; Daytime; Female; Humans; Internet; Inter‐work intervals; Japan; Male; Middle Aged; Occupational Diseases - etiology; Occupational health; Original; Personnel Staffing and Scheduling; Quality; Rest - physiology; Sleep; Sleep - physiology; Sleep deprivation; Sleep problems; Sleep time; Sleep Wake Disorders - etiology; Surveys and Questionnaires; Time Factors; Trend analysis; Work Schedule Tolerance - physiology; Workers; Young Adult; Sleep time; Inter-work intervals; Sleep problems
• ISSN: 1341-9145; 1348-9585; 1348-9585
• DOI: 10.1539/joh.17-0165-OA

Abstract: Objectives: This study aimed to describe the sleep quantity, sleep quality, and daily rest periods (DRPs) of Japanese permanent daytime workers. Methods: Information about the usual DRP, sleep quantity, and sleep quality (Japanese version of the Pittsburgh Sleep Quality Index: PSQI-J) of 3,867 permanent daytime workers in Japan was gathered through an Internet-based survey. This information was analyzed and divided into the following eight DRP groups: <10, 10, 11, 12, 13, 14, 15, and >-16 h. Results: The sleep durations for workers in the <10, 10, 11, 12, 13, 14, 15, and >-16 h DRP groups were found to be 5.3, 5.9, 6.1, 6.3, 6.5, 6.7, 6.7, and 6.9 h, respectively. The trend analysis revealed a significant linear trend as the shorter the DRP, the shorter was the sleep duration. The PSQI-J scores for the <10, 10, 11, 12, 13, 14, 15, and >-16 h DRP groups were 7.1, 6.7, 6.7, 6.3, 6.0 (5.999), 5.6, 5.2, and 5.2, respectively. The trend analysis revealed a significant linear trend as the shorter the DRP, the lower was the sleep quality. Conclusions: This study described sleep quantity, sleep quality, and DRP in Japanese daytime workers. It was found that a shorter DRP was associated with poorer sleep quantity as well as quality.