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

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