The association between screen time trajectories and the comorbidity of depression and anxiety

Depression and anxiety are often comorbid among adolescents. Adolescent screen time changes over time. This study investigates the association between screen time trajectories and the comorbidity of depression and anxiety from a longitudinal perspective. The data were collected from an ongoing prospective puberty cohort which was established in 2014 from Chongqing, China. 838 participants (52.03 % female; wave 1 mean age = 8.62, SD = 1.15) were followed up from 2014 to 2020. Questions about screen time were administered every six months. Trajectories of screen time were identified using latent class growth analysis. Children's Depression Inventory (CDI) and Screen for Child Anxiety Related Disorders (SCARED) were used to measure depression and anxiety. Latent profile analysis was used to identify the subtypes of comorbidity of depression and anxiety. Logistic regression was used to explore the association between screen time trajectory and the comorbidity of depression and anxiety. Three distinct trajectories of screen time were identified: Group Low (68.26 %) had consistently low screen time, Group High (26.37 %) had high screen time and Group Increasing (5.37 %) was characterized by an increasing screen time. Four subtypes of the comorbidity of depression and anxiety were fitted ("High comorbidity", "Low comorbidity", "Low depression symptoms" and "No symptoms"). Group Increasing and Group High were associated with "Low comorbidity" and "Low depression symptoms". Group Increasing was more likely to be the "high comorbidity" both boys and girls. However, Group High was associated with "high comorbidity" only in girls. The results of this study may inform future research and provide possible intervention targets.