Sleep Wake Patterns and Nocturnal Sleep Parameters in the Morning and Evening Types / 신경정신의학

ABSTRACT

OBJECTIVES: The aim of our study was to compare sleep wake patterns and nocturnal sleep parameters between the morning type (MT) and evening type (ET). METHODS: The Morningness-Eveningness Questionnaire, Pittsburgh Sleep Quality Index (PSQI), and Korean version of the Epworth Sleepiness Scale (KESS) were administered to subjects recruited among visitors to the Chuncheon National Museum from 2010 to 2011. Actigraphy data (Actiwatch-2, Philips-Respironics Co.) were collected from eight MT (Age 38.0+/-3.8, M F=2 6), 12 neither type (NT) (Age 34.2+/-5.1, M F=2 10), and nine ET (Age 30.3+/-6.8, M F=2 7) subjects. RESULTS: Scores for PSQI and KESS did not differ significantly among the MT, NT, and ET groups. No differences in time in bed, total sleep time, sleep efficiency, wake after sleep onset, sleep latency, and fragmentation index were observed among the three groups. In the ET group, the mean wake time on free days was significantly later, and the mean sleep duration on free days was significantly longer, compared with those of the MT group (p<0.01). CONCLUSION: No differences in sleep quality, daytime sleepiness, and nocturnal sleep parameters were observed among the MT, NT, and ET groups. Compared to MT subjects, ET subjects showed later wake time and longer sleep duration on free days.