Background: The primary objective was to determine the dose-response relation between screen time (television + computer) and the metabolic syndrome (MetS) in adolescents.
Methods: The study sample included 1803 adolescents (12-19 years) from the 1999-04 US National Health and Nutrition Examination Surveys. Average daily screen time (combined television, computer and video game use) was self-reported. MetS was defined according to adolescent criteria linked to the adult criteria of the National Cholesterol Education Program (> or =3 of high triglycerides, high fasting glucose, high waist circumference, high blood pressure and low HDL cholesterol).
Results: After adjustment for relevant covariates, the odds ratios (95% confidence intervals) for MetS increased in a dose-response manner (P(trend) < 0.01) across < or =1 h/day (1.00, referent), 2 h/day (1.21, 0.54-2.73), 3 h/day (2.16, 0.99-4.74), 4 h/day (1.73, 0.72-4.17) and > or =5 h/day (3.07, 1.48-6.34) screen time categories. Physical activity had a minimal impact on the relation between screen time and MetS.
Conclusions: Screen time was associated with an increased likelihood of MetS in a dose-dependent manner independent of physical activity. These findings suggest that lifestyle-based public health interventions for youth should include a specific component aimed at reducing screen time.