Study finds COVID-19 pandemic has long-lasting effects on adolescent mental health and substance use

The COVID-19 pandemic has had a long-lasting impact on adolescent mental health and substance use, according to a new population-based study based on survey responses from a nationwide sample of over 64,000 13–18-year-old North American and Icelandic adolescents assessed prior to and up to two years into the pandemic.

The study was conducted by faculty at Columbia University Teachers College and Mailman School of Public Health and a team of Icelandic and other North American clinical, behavioral and social scientists. The findings are published in published in The Lancet Child & Adolescent Health.

This same research team published a population-based study in The Lancet Psychiatry in 2021 showing an increase in depressive symptoms and decrease in mental well-being among 13–18-year-old adolescents within one year of the global spread of the COVID-19 pandemic. A decline in substance use, in particular cigarette smoking, e-cigarette use and alcohol intoxication, was also observed. Expanding on these findings, this new study shows that the negative effect on adolescent mental health has been persisted up to two years into the pandemic.

"It is worrisome that we still see an increase in mental health problems among adolescents two years into the pandemic. And this is occurring despite social restrictions having been eased in Iceland," said Thorhildur Halldorsdottir, assistant professor of psychology at Reykjavik University and senior author of the study.

The initial decrease in cigarette smoking and e-cigarette use observed shortly after the arrival of the pandemic was also maintained up to two years into the pandemic. The frequency of adolescent alcohol intoxication, however, appeared to be returning to pre-pandemic levels.

"It is of course positive to see that the reduction in cigarette smoking and vaping has been maintained," said Dr. Ingibjorg Eva Thorisdottir, chief data analyst at Planet Youth and lead author of the study. She continued, "We will need to monitor alcohol intoxication among adolescents in years to come, especially given the increase in mental health problems."

The association of immigration status, residency, parental social support and nightly sleep duration with adolescent mental health and substance use was also examined in this study. Parental social support and an average of 8 hours or more of sleep per night was associated with better mental health and less substance use among adolescents.

The relationship between immigration status and residency with adolescent mental health was less clear. These findings suggest that stress exposure, like the COVID-19 pandemic, affects all adolescents to some extent rather than only vulnerable subgroups.

As such, "policymakers should consider implementing large-scale evidence-based prevention efforts focusing on depressive symptoms to mitigate the negative effect of the pandemic," said John Allegrante, the Charles Irwin Lambert Professor of Health Behavior and Education at Teachers College and professor of sociomedical sciences at Columbia Mailman School of Public Health, and a senior collaborating investigator on the study.