Sleep duration change among adolescents in Canada: Examining the impact of COVID-19 in worsening inequity

Purpose: The purpose of this study was to assess if adolescent sub-populations in Canada (i.e., based on race/ethnicity, sex/gender, socioeconomic status, and urbanicity groups) experienced a larger change in sleep duration and guideline adherence between 2019 and 2020 (pre-pandemic) and the 2020-2021 (mid-pandemic) school years. Methods: Longitudinally linked data from 2019 to 2020 (pre-pandemic) and 2020-2021 (mid-pandemic) of a prospective cohort study of secondary school students (M = 14.2, SD = 1.3 years, N = 8209) in Canada were used for analyses. Regression modelling tested the main effects of race/ethnicity, sex/gender, socioeconomic status, and urbanicity on changes in sleep duration as well as adherence to Canada's 24-h Movement Guidelines for sleep (8-10 h/night). Interactions between identity variables (race/ethnicity or sex/gender) and other main effect variables were subsequently tested. Results: Females gained more sleep (4.5 [1.5, 7.5] min/day more) and increased guideline adherence (AOR = 1.16 [1.04, 1.30] than males on average. Asian race/ethnic identity was associated with less sleep gain than White identity -10.1 [-19.4, -0.8], but not guideline adherence. Individuals in large urban areas gained less sleep and adhered less to guidelines than individuals from any other level of urbanicity (-21.4 [-38.5, -4.2] to -15.5 [-30.7, -0.2] min/day). Higher individual SES scores were associated with greater sleep gain (linear trend: 11.16 [1.2-21.1]). The discrepancies in sleep gain and guideline adherence between males and females were significantly modified by race/ethnicity and urbanicity. Discussion: Increases in sleep duration may be one of the few benefits to adolescents during the COVID-19 pandemic but were not equally distributed across sub-populations. Efforts to promote better sleep adherence may need to account for sex/gender differences, especially in less urbanized areas and certain racial/ethnic groups.