Sleeping in multicultural societies: The longitudinal interplay between adolescents' sleep health and intercultural...

Adolescents' sleep is intertwined with their well-being and daily life experiences. Sleep health is conceptualized as a multidimensional construct encompassing complementary components, including subjective dimensions (e.g., perceived sleep quality and sleep problems, assessed via self-reports) and quantifiable aspects (e.g., sleep duration and sleep efficiency, assessed via actigraphy). During adolescence, poor sleep health is increasingly recognized as a public health concern. However, there is a lack of evidence on how adolescents' interactions in contemporary societies, characterized by increasing cultural diversity, are intertwined with sleep health. Thus, this study investigated the reciprocal longitudinal associations between sleep health, considering subjective dimensions (i.e., sleep problems) and quantifiable aspects (i.e., sleep efficiency and duration), and the intercultural interactions of adolescents (quantity and quality) in two different life contexts (i.e., school and leisure time). A total sample of 1470 adolescents living in North-Eastern Italy (M _age = 15.71, SD = 1.22, 47.58% females, 20.58% with a migrant background) wore an actigraph for one week and completed questionnaires about intercultural interactions and sleep health four times across one year. Results of Random-Intercept Cross-Lagged Panel models showed that negative interactions were consistently associated with lower subjective sleep health, lower sleep efficiency, and shorter sleep duration. Conversely, positive intercultural interactions were positively associated with better sleep efficiency, although these effects were mainly observed at the between-person level. These findings underscore the nuanced interplay between the quality of intercultural interactions and both the subjective and objective indicators of sleep health. These findings allow for a conceptualization of adolescents' sleep as a socially embedded phenomenon shaped by the cultural contexts in which young people live.