Subjective daytime sleepiness in schoolchildren.

Abstract

OBJECTIVES: The aim of this study was to find out how the occurrence of subjective daytime sleepiness (SDS) in schoolchildren had changed after 2 years follow-up and which were the predictors associated with persistence and appearance of SDS. METHODS: A total of 107 schoolchildren with SDS (Group 1) and an equal number without SDS (Group 2) were chosen to take part in the questionnaire study (age range 12-20 years). The questions concerned sleeping habits, sleep disorders and daytime sleepiness of the child and the family, progress at school and TV/video watching of the child, and social background of the family. A bivariate method (Pearson's chi-square) was used as a statistical tool. RESULTS: We received 68 replies (64%) from Group 1 and 75 (70%) from Group 2. Fifty-four schoolchildren were still sleepy in Group 1 and 28% had become sleepy in Group 2. The persistence of SDS in Group 1 was related to older age, irregular sleeping habits, frequent night waking and the fathers' sleep difficulties. The appearance of SDS in Group 2 was related to a high average grade at school. CONCLUSION: A delayed sleep phase rhythm and problems staying asleep are obvious causes of persistent SDS, but the stress of schoolwork can also cause daytime sleepiness in schoolchildren.