Temporal fluctuations of adolescent suicides in OECD countries from 1990–2019

• Suicides decreased in this century, but decreasing trend has been attenuated since the late 2010s. • These tendencies are more pronounced among adolescents. • In this century, suicide prevention in promoting the health of adolescents has been becoming increasingly. In this century, globally suicides have decreased, but decreasing trend was attenuated since the late 2010s, with these tendencies being more pronounced in adolescents. This study identified actual trends and risks of adolescent suicide in OECD countries during 1990–2019. Fluctuation of adolescent (10–25 years) age-standardized death rate (ASDR), crude-mortality rate (CMR) and percentage of suicide per total-deaths (PTD) in 37 OECD countries obtained from “WHO Mortality Database” was analyzed by joinpoint regression. Fixed effects of gross domestic product per capita (GDPC) obtained from “OECD Data Explore” were determined using hierarchical linear model. Adolescent ASDR-suicide increased. Adolescent ASDR-suicide increased among males and females in Asia, Central/South America, and females in North America, unchanged in males and females in Oceania and males in North America, but decreased in males and females in Europe. PTD-suicide among adolescents in all regions consistently increased in 1990–2019 (with female predominance). Surprisingly, PTD-suicide in adolescents in Asia was approximately 50 % in the late 2010s. Fixed effects of males ASDR caused by traffic accidents and of females ASDR caused by violence positively related to ASDR-suicide of adolescent males and females, respectively. Fluctuation adolescent males and females ASDR-suicide was not uniform across five regions among OECD. Contrary, adolescent PTD-suicide in five regions indicated increasing in all five regions; however, those in Asia and Oceania markedly larger compared to other regions. These results suggest that suicide prevention among adolescent health activities is lagging compared to other causes of death, especially in Asia and Oceania.