0388 Comparison of objective and subjective sleep evaluations based on with or without insomnia symptoms among Japanese city employees

Abstract

Abstract Introduction Discrepancies between subjective and objective assessments of sleep duration and onset latency have been reported among insomnia patients. However, such discrepancies have not been well studied in the general population or working populations with sleep EEG measurements. The aim of this study was to compare subjective and objective assessments of sleep at home in a working population. Methods Between 2017 and 2019, a questionnaire survey including the Athens Insomnia Scale (AIS) and home 1-Ch electroencephalograph (EEG) measurements were conducted among municipal employees in Koka, Shiga Prefecture, Japan (NinJaSleep study). Sleep duration and sleep onset latency (SL) on weekdays answered in the questionnaire were used as the subjective evaluation. Sleep duration and SL determined with 1-Ch EEG were used as the objective evaluation. AIS≥6 was defined as having insomnia. The study protocol was approved by the Ethics Committee of the Shiga University of Medical Science. Results 646 employees (44.7 ± 11.5 years, AIS: 5.4 ± 3.6 points) participated in the study. In the with-insomnia group (AIS≥6, n=274), no significant difference was found between subjective and objective sleep duration (347.1±75.8 min vs. 355.1±78.9 min, p=0.153), and subjective SL was longer than objective SL (24.5±20.2 min vs. 19.5±18.8 min, p=0.002). In the without-insomnia group (AIS< 6, n=372), no significant differences were found between subjective and objective evaluations in both sleep duration (372.3±64.6 min vs. 369.9±78.6 min, p=0.597) and SL (18.9±15.8 min vs. 16.9±12.3 min, p=0.259). Conclusion In the with-insomnia group, subjective SL was perceived longer than the objective SL. No differences were found between subjective and objective sleep duration both in with and without insomnia groups, which may come from the study performed in a working population. Support (if any) Investigator-Initiated Studies Program of Merck Sharp & Dohme Corp. / MSD K.K. The funders had no role in the study design, data collection, analyses, interpretation, writing of the manuscript, or in the decision to publish the results.