BACKGROUND: The aim of the study was to investigate how general family relations, reported changes in family interaction and involvement with peers during the Covid-19 pandemic, and following rules and recommendations during the pandemic relate to adolescent smoking, alcohol use, inebriation, and use of narcotics during Covid-19.

METHODS: An online national survey of Swedish adolescents (n = 1818) aged 15-19 years was conducted in June 2020. Hierarchical regression analysis was used to predict adolescents' reported change in substance use during the pandemic. Person-oriented analyses, were used to identify clusters of participants characterized by similar patterns of substance use following ANOVA analysis with Scheffe post hoc tests testing differences between clusters in terms of family relations, reported changes in family interaction and involvement with peers during the Covid-19 pandemic, and following rules and recommendations during the pandemic.

RESULTS: Higher general family conflict, increased involvement with peers, a strained relationship with parents, and less compliance with rules and restrictions during the pandemic predicted a reported increase in adolescent substance use during this period. The grouping of scores for adolescent smoking, alcohol use, inebriation, and use of narcotics resulted in a six-cluster solution. One cluster (n = 767) either did not use or had decreased use of substances during the Covid-19 pandemic. Five other clusters, thus risk clusters, had retained or increased use of substances during the pandemic. Poor general family relations, increased peer involvement, and difficulties to conform to the rules and restrictions during the covid-19 pandemic were characteristics of risk clusters.

CONCLUSIONS: Most of adolescents in our study did not increase their substance use during the pandemic. However, adolescents with poor family relations who turn to peers during stressful times and who have difficulty following the government's rules and restrictions, are at risk of increased substance use during the pandemic. This is a potential threat both to adolescents themselves and others in their surroundings which is why at-risk adolescents and their families need more attention from public health and social services during this time of crisis.