Associations between TV viewing, sitting time, physical activity and insomnia among 100,839 Brazilian adolescents

Our aim was to examine the relationship between insomnia and levels of physical activity (PA) and time spent sitting and TV viewing among Brazilian adolescents. Data from the Brazilian Scholar Health Survey, a nationally representative survey of 9th grade adolescents [mean: 14.28 years (range: 11-18 years)] conducted in 2015 (n = 100,839) were used. Self-reported insomnia, TV viewing, sitting time and total PA (adapted International PA Questionnaire) were collected. Chronological age, race, type of city (capital or interior) country region, goodies ingestion and ultra-processed foods ingestion were covariates. Logistic regression analyses were conducted to assess the associations. A higher sitting time and TV viewing (≥8 h/day) was associated with a higher risk of insomnia among boys [sitting time: OR = 2.39 (95%CI = 1.88-3.04); TV:OR = 2.49(95%CI = 1.92-3.22) and girls [sitting time: OR = 2.17(95%CI = 1.84-2.57; TV:OR = 1.72(95%CI = 1.44-2.04)]. More than 4 h of sitting time per day was associated with higher risk of insomnia in adolescents who comply [boys: OR = 1.43(95%CI = 1.19-1.73); girls: OR = 1.66(95%CI = 1.41-1.94)] and who do not comply with the 300 min/week of physical activity recommendation [boys = OR = 1.35(95%CI = 1.13-1.60); girls: OR = 1.38(95%CI = 1.20-1.57)]. Our data suggest that higher levels of TV viewing or sitting are associated with sleep difficulties in this large cohort of adolescents, irrespective of their physical activity behavior.