Exposure to electronic devices and sleep quality in adolescents: a matter of type, duration, and timing.

OBJECTIVES

The objective was to describe (1) the type, (2) the amount of use, and (3) the time of usage of electronic devices, for school days and weekends, as well as its impact on adolescents' sleep quality.

DESIGN

A cross-sectional study using hierarchical regressions accounting for confounding sleep-related variables was used.

SETTING

The participants were from six public schools in Porto Alegre, Brazil.

PARTICIPANTS

The participants included 177 students of both sexes aged between 11 and 18 years.

MEASUREMENTS

An electronic usage diary assessed the span of time during which the electronic device was used (separated by "TV and computer monitors", "tablets, e-readers and portable video games," and "cell phones") for school days and weekends. The Munich Chronotype Questionnaire was used to assess sleep duration, midpoint of sleep, and social jetlag. Sleep quality was assessed using the Pittsburgh Sleep Quality Index.

RESULTS

Greater nighttime use and last time of use of cell phones at night are associated with worse sleep quality in univariate analyses. A hierarchical regression model shows that poor sleep quality associates with shorter sleep duration on school days and with a delayed midpoint of sleep on weekends. Electronic device use did not reach statistical significance in the regression model with confounding factors.

CONCLUSIONS

Adequate sleep duration is imperative to maintain a good sleep quality on school days, independently of the use of cell phones. It is important to underpin the need for evaluation of sleep phase and chronotype in future research on the topic aiming to elucidate its relationship with electronic use on school-free days.