COVID-19 pandemic impact on sleep habits, chronotype and health-related quality of life among high school students: a longitudinal study

The COVID-19 pandemic has challenged the population of affected areas in multiple dimensions. Adolescents have been especially affected with school closure and home confinement. The impact of the pandemic on sleep habits and quality of sleep and quality of life among adolescents have not been adequately characterized. We hypothesized that the COVID-19 pandemic induced an evening shift of the daily rhythm among adolescents and adversely affected sleep quality and quality of life of high school students. Students were questioned about their usual bed and wake-up times and answered the Pittsburg Sleep Quality Index Questionnaire (PSQI), the Epworth Sleepiness Scale (ESS), the Morning-Eveningness Questionnaire (MEQ) and the World Health Organization Quality of Life Questionnaire (WHOQOL) before and during the pandemic. Ninety-four students (64% females, aged 15+1 years) participated in both phases of the study. Students delayed bed and wake-up times in 1.5[0.5-2.0] and 2.0[1.5-2.5]h, respectively. Chronotype (MEQ) shifted towards eveningness during the pandemic. Sleep duration increased and quality of sleep (PSQI) improved only among those students with shorter sleep duration before the pandemic. During the pandemic, the physical and psychological domains of WHOQOL worsened but the environmental domain improved as compared to the study before the pandemic. High school students delayed bed and wake-up times and shifted chronotype towards eveningness during the COVID-19 pandemic. The worsening of the physical and psychological WHOQOL domains and improvement of the environmental domain highlights the conflicting experiences that high school students are facing during the COVID-19 pandemic.