Changes in the difference between subjective and objective sleep duration according to sleep duration or sleep disordered breathing: The Nagahama Study

Background: While self-reported subjective sleep duration (SSD) usually tends to exceed actual sleep duration (objective sleep duration, OSD), factors related to the differences between SSD and OSD are unknown. It was reported that sleep disordered breathing (SDB) altered the perception of sleep habits. Aims and Objectives: This study aimed to compare SSD with OSD and to examine whether SDB was related to the differences between SSD and OSD. Methods: This cross-sectional study evaluated 6908 community residents in Nagahama city, Japan. SSD was determined by a self-administered questionnaire while OSD was measured by wrist actigraphy and a sleep diary. SDB was assessed according to the 3% oxygen desaturation index modified for OSD obtained by actigraphy. Results: In groups of participants with SSD Conclusions: OSD tended to be longer than SSD in those who reported short SSD, while the opposite occurred in those reporting long SSD; however, this tendency was offset at 5.7 hours. OSD was shorter than SSD as the severity of SDB increased. These data will help to better assess patients’ complaints about sleep duration.