Added screen time linked to more depression in adolescents, study findsBMJ 2019; 366 doi: https://doi.org/10.1136/bmj.l4691 (Published 16 July 2019) Cite this as: BMJ 2019;366:l4691
Increased use of social media and computers and longer television viewing times are linked to higher rates of depressive symptoms in adolescents, but playing video games does not increase depression, a Canadian study1 has found.
“To our knowledge, this study is the first to use developmental data from a large sample of adolescents to examine the association between four types of screen time and depression,” said the study authors, led by Elroy Boers, postdoctoral researcher at the department of psychiatry, University of Montreal, Canada.
The researchers added, “The most important finding was that increased social media and television use were associated with lower self esteem.” They suggested that adolescents’ social media and television use should be regulated to prevent the development of depression and to reduce exacerbation of existing symptoms over time.
The study measured the association between screen time and depression in a secondary analysis of a drug and alcohol prevention programme in 3826 adolescents (mean age 12.7, standard deviation 0.5 years). They were recruited from 31 schools in Montreal and followed up with annual surveys over four years from 2012.
Participants were asked how much time they spent each day playing video games, on social networking sites, carrying out other computer activities, and watching television. Symptoms of depression were measured using self assessment of seven symptoms, including feeling lonely and feeling sad, based on the depression subscale of the Brief Symptoms Inventory.
Results, reported in JAMA Paediatrics, showed significant associations between use of social media and computers and depression symptoms when making comparisons between different individuals (using between person comparisons) and when comparing changes in screen time for individual adolescents (within person comparisons).
For every one hour increase in time spent using social media, the adolescents showed a 0.64 unit (on a scale from 0 to 20) increase in severity of depressive symptoms over four years (95% confidence interval, 0.32 to 0.51).
There was a similar increase for every additional one hour of computer use (0.69 unit increase in depressive symptoms, 95% CI, 0.47 to 0.91). Within person comparisons also showed increased depressive symptoms with greater use of social media or computers.
There was no between person link between television viewing and depression but the within person analysis showed a 0.18 unit increase in depressive symptoms for every one hour increase in viewing (95% CI, 0.09 to 0.27). However, no significant associations were found between video gaming and depression.
To explore the possible underlying causes of the link between screen time and depression the researchers measured self esteem, assessed with the Rosenberg Self Esteem Scale, a self report instrument of 10 items on a four point scale.
Increased social media and television use were both associated with lower self esteem over time. “It might be that repeated exposure to idealised images on social media and television decreases self esteem,” suggested the authors of the study, which was funded by the Canadian Institutes of Health Research and other non profit research grants.