In a recent study published in BMJ Mental Health, researchers determined the relationships between problematic smartphone usage (PSU) and anxiety, depression, and insomnia among United Kingdom (UK) adolescents.

Mental illness is a leading cause of disability in the United Kingdom, with depression and anxiety particularly prevalent among teenagers. Smartphone use has increased, and there is conflicting information concerning the relationship between screen time and anxiety and depression. Some claim mobile use is common among children and adolescents, while others believe it is maladaptive.

Most previous studies are cross-sectional, raising doubts regarding causality. Some longitudinal studies in Southeast Asia have found a complicated link between PSU and depression, with psychiatric issues increasing PSU. However, prior research discovered that psychosocial adjustments affected PSU rehabilitation or persistence.

In the present mixed methods, prospective cohort, and longitudinal study, researchers investigated whether smartphone usage is associated with poor psychiatric health outcomes. They also explored adolescent understanding of smartphone usage, related pros and cons, and the steps taken to curtail their use.

The researchers included 69 students aged between 13 and 16 years from two secondary schools to assess their mobile usage, sleep, and mood using semi-structured questionnaires at study initiation and after four weeks. They used the Smartphone Addiction Scale Short Version (SAS-SV) to assess PSU exposure and followed the participants between March 28 and June 3, 2022.

The primary study outcome was anxiety, ascertained using the Generalized Anxiety Disorder Questionnaire (GAD-7). GAD-7 scores below 5.0 indicated no anxiety, 5.0 to 9.0 denoted mild anxiety, 10 to 14 moderate anxiety, and ≥15 severe anxiety. Secondary study outcomes included changes in depressive symptoms based on the nine-item Patient Health Questionnaire (PHQ9) and insomnia severity, measured using the Insomnia Severity Index (ISI).

PHQ9 scores below 5.0 indicated no depression, 5.0 to 9.0 denoted mild depression, 10 to 14 moderate depression, and ≥15 severe depression. ISI scores below 7 indicated non-significant insomnia, 8.0 to 14 subclinical insomnia, 15 to 21 moderate-intensity clinical insomnia, and 22 to 28 severe-intensity clinical insomnia. The researchers used linear regressions for analysis, adjusting for age and biological sex. They used Cronbach’s alpha values to assess the internal reliability between the study outcomes and performed a thematic analysis of free-text responses.

The median participant age was 15 years; 44% were female, and 59% were white. The overall PSU prevalence was 15%, higher among females (17%) than males (11%). PSU group individuals used TikTok, Snapchat, and music-related applications the most, while the non-PSU group used YouTube, music applications, and TikTok more often.

Among PSU participants, 44% developed moderate-severe anxiety compared to 26% of those without PSU exposure. Among PSU-exposed individuals, 56% experienced depressive symptoms compared to 36% without PSU exposure, and 22% of PSU-exposed and 23% of non-exposed individuals reported sleep difficulties. The team found linear associations between PSU and changes in anxiety, depression, and insomnia, with increases of 10 in PSU over four weeks increasing anxiety, depression, and sleep difficulties by 2.2, 1.4, and 2.1, respectively. There was good reliability between the primary and secondary study outcomes.

Among the participants, 90% tried to limit smartphone use, with 83% of the non-PSU group finding that putting their smartphones on silent was effective and 100% of the PSU group finding it somewhat effective. Seventy-two percent of non-PSU group individuals found turning off notifications effective, whereas 78% of PSU group individuals found it somewhat effective. Some found it arduous to control usage, using apps to set time limits, and some believed it should be an individual initiative.

The themes indicated mixed effects of smartphone use on relationships and mood, adverse effects on performance and productivity at school, and a wish to decrease smartphone use durations. While smartphone use facilitates communication with friends and family, especially those outside their local area, it could distance users from family, increase irritability, and affect social interactions.

Smartphones could distract students, reducing productivity and time for schoolwork. However, online educational resources could be beneficial. The effect of smartphone use on school performance varies by time spent using the device and prioritization of other tasks like exams. Smartphone use could improve mood by providing entertainment and reducing stress; however, adverse effects included self-comparison, cyberbullying, exposure to scary content, and suicidal thoughts. Prolonged smartphone use can increase stress, suggesting self-control and effective time management are crucial.

To conclude, based on the findings, increased mobile use could increase anxiety, depression, and sleep difficulties among UK adolescents. While most recognize the consequences of excessive smartphone usage and manage it effectively, a few require assistance applying reduction techniques to control their utilization.

Journal reference:

Carter B. et al., ‘There’s more to life than staring at a small screen’: a mixed methods cohort study of problematic smartphone use and the relationship to anxiety, depression, and sleep in students aged 13–16 years old in the UK, BMJ Ment Health 2024;27:1–7. DOI:10.1136/bmjment-2024-301115 https://mentalhealth.bmj.com/content/27/1/e301115