0093 Chronotypic characteristics of sleep, mental health, and daily life of Japanese university of health sciences students

Abstract

Abstract Introduction Students’ lifestyles change after entering the university negatively impacting effective sleep regulation, daytime alertness, motivation to learn, and mental health. An evening chronotype has been increasingly associated with negative impacts upon performance and well-being. Greater understanding of chronotype differences in sleep-related, mental health, and daily life characteristics is needed to develop a sleep health promoting intervention. Methods Cross-sectional descriptive design among health sciences students (nursing, occupational therapy and physical therapy) in a Japanese university. The Japanese version of the Morningness-Eveningness Questionnaire (MEQ-J) was used to create morning (M), intermediate (I), and evening (E) chronotype groups. One-way analysis of variance was used to investigate differences among chronotype groups by sleep, mental health, and daily life characteristics. We assessed insomnia severity (ISI-J), sleep quality (PSQI-J), sleep hygiene (SHPS-J), daytime sleepiness and dysfunctional sleep beliefs; depression (JCES-D) and anxiety; and time use in club, commuting, sleep, and work, as well as engagement in meaningful day-to-day activities (EMAS-J), significant group differences were explored post-hoc. Results Of 369 students there were 21% classified as M chronotype, 63% as I, and 16 % as E; an approximate 1:3:1 ratio. Sleep quality was progressively better as chronotype advanced from E, to I, to M (PSQI-J: d range 0.41-1.07); along with sleep problems being less likely (ISI-J: d range 0.45-1.16). Sleep hygiene practices were most effective for the M chronotype, followed by I then E (SHPS-J: d range 0.49-1.14). No group differences were found in daytime sleepiness or dysfunctional sleep beliefs. Depression symptoms were greater in the E chronotype compared to I and M (JCES-D: d range 0.52-0.84). M chronotypes reported the longest commuting times (d range 0.45-0.55). No differences were found in sleep duration or time spent in other activity types. Lastly, M chronotypes reported engaging in more meaningful activities compared to E (EMAS-J: d = 0.47). Conclusion Sleep health lifestyle intervention should target chronotype preference to be less evening-like, thereby promoting sleep quality and mental health. Intervention could tailor sleep hygiene beliefs and skills to address sleep timing, pre-sleep arousal and environment regulation according to individuals’ daily life characteristics and chronotype differences. Support (if any)