While substance use declined, social isolation has especially affected the mental health of girls

A study of over 59,000 Icelandic adolescents by a team of Icelandic and North American behavioral and social scientists—including specialists from Planet Youth —has found that COVID-19 has had a significant, detrimental impact on adolescent mental health, especially in girls.

The study is the first to investigate and document age- and gender-specific changes in adolescent mental health problems and substance use during the COVID-19 pandemic, while accounting for upward trends that were appearing before the pandemic.

The study found that negative mental health outcomes were disproportionately reported by girls and older adolescents (13-18-year-olds), compared to same-age peers prior to the pandemic. At the same time, it revealed a decline in cigarette smoking, e-cigarette usage and alcohol intoxication among 15-18-year-old adolescents during the pandemic.

Ingibjorg Eva Thorisdottir, chief data analyst at Planet Youth, was the principal investigator and lead author of the report.

Thorhildur Halldorsdottir, a clinical psychologist and assistant professor of psychology at Reykjavik University who is the study co-principal investigator, said the study represents a “landmark contribution to what we now know about just how psychologically devastating being socially isolated from peers and friends during the ongoing pandemic has been for young people.”

Inga Dora Sigfusdottir, professor of sociology at Reykjavik University, scientific director of Planet Youth, and research professor of health education at Teachers College, said the study “differs in methodology from previous studies in that it tracked population-based prevalence of mental health outcomes and substance use over several years in order to better understand the potential effects of COVID-19 from recent upward trends in adolescent mental health problems.

According to the researchers, prior studies have not been designed to determine whether clinically relevant levels of depression—as opposed to self-reported depressive symptoms—and substance use have increased during the pandemic.

Previous studies of adolescents during COVID-19 found evidence of increased mental health problems and certain types of substance use that had been rising before the pandemic. This study, however, compares current data with several pre-pandemic time points, which enabled the researchers to separate the effect of COVID-19 from other recent, downward trends in adolescent mental health.

The implication of the new study is that interventions intended to lessen the negative impact of the pandemic on adolescent mental health might help improve the mental health outlook for young people around the world who have been caught up in the pandemic, Allegrante said.

“Isolation during the pandemic has been universal and it is global, and it is having a clinically important, negative impact on young people who have not been in school during the pandemic. The study shows that population-level prevention efforts, especially for girls, are warranted,” but that “more study is needed to determine the long-term effects of quarantine and being socially isolated from one’s peers, including the effects on learning and academic achievement and relationships with parents, siblings, and peers.”

Alfgeir L. Kristjansson, Senior Scientist at Planet Youth and Associate Professor of Public Health at West Virginia University and a co-author of the study, said the “results underline the significance of social relationships in the health and well-being of youth and the importance of nurturing and maintaining strong social support mechanisms in their lives. The Lancet Psychiatry study report highlights these findings at population scale.” Kristjansson was a postdoctoral fellow with Allegrante at Teachers College during 2010-2012.

Teachers College senior professor of health education John Allegrante, an applied behavioral scientist and an affiliated professor of socio-medical sciences at the Columbia University Mailman School of Public Health, is a coauthor and collaborating senior investigator on the study, published June 3 in The Lancet Psychiatry.

“The decrease observed in substance use during the pandemic may be an unintended benefit of the isolation that so many adolescents have endured during quarantine,” Allegrante said.

In a commentary that accompanies the article’s publication, Gertrud Sofie Hafstad and Else-Marie Augusti, both senior researchers at the Norwegian Centre for Violence and Traumatic Stress Studies in Oslo, write that the study “clearly shows that gauging the mental health status of adolescents over time is of imminent importance.”

Additional investigators and coauthors on the study, which was funded by the Icelandic Research Fund, include Bryndis Bjork Asgeirsdottir, professor of psychology at Reykjavik University; Heiddis Bjork Valdimarsdottir, professor of psychology at Reykjavik University and the Icahn School of Medicine at Mount Sinai; and Erla Maria Jonsdottir Tolgyes, chief project officer, and Jon Sigfusson, managing director, both at Planet Youth.