Evaluation of social jetlag and chronotypes in Indian school-going adolescents

School-going students' school time acts as a zeitgeber during the weekdays, and in the weekends, due to the absence of the zeitgeber, they show free run and wake up late in the morning. This may result in poor health hazards in adolescents.

The aim of this study was to assess the prevalence of social jetlag along with the distribution of their chronotype in school-going adolescents.

This is a cross-sectional study conducted between May and June 2019 with the help of the MCTQ (Munich Chronotype Questionnaire) and MEQ (Morningness and Eveningness Questionnaire) in the adolescent population (N = 1154).

The study was performed using the Mann-Whitney U test to compare continuous variables of sleep parameters between workdays and free days. The significance was taken at P < 0.05.

The results showed that out of the total population, 81% were morning type and 67% of adolescents were socially jetlagged. There was a significant delay in the time to bed on free days by 1.88 hours and a significant delay in the wake-up time by 2.46 hours. The total sleep duration was also significantly higher on free days by 1.88 hours in the population.

This is our first study in the Indian population to show that morning-type individuals showed irregular sleep timings and were more socially jetlagged. This needs to be focused on by the school authorities and government to keep a flexible school timing for the students on the basis of their chronotype for their better academic performance.