Abstract
Young people’s mental and substance use disorders are a significant public health issue worldwide. A large proportion of the world’s disease burden among young people is attributable to mental health disorders. This study examines the prevalence of mental and substance use disorders, the incidence of self-harm behaviors, years lived with disability, and years of life lost by country-level income groups and gender among young people (10–24 years) in 185 countries at two time points: 1990 and 2019. A descriptive study was conducted using secondary data extracted from the Global Burden of Disease Study (GBD) 2019 to estimate the prevalence of mental health and substance use disorders, as well as self-harm behaviors among young people. Percentage changes in 1990–2019, 95% uncertainty intervals (UIs), and correlations with the socio-demographic index, sustainable development goals were examined. The findings showed that globally, the prevalence of mental and substance use disorders among young people of both genders slightly decreased from 1990. However, these rates varied significantly across country-level income groups and sexes. High-income countries showed significantly the highest increase of mental health disorder rates at these time points, while lower-middle-income countries had the greatest decrease in the study. Furthermore, females displayed higher incidence rates of self-harm at younger ages compared to males across all income-based groups. These findings provide valuable insights for policymakers, enabling them to better understand the situation and make data-driven policy decisions. This includes estimating the economic burden of disorders, planning services, and allocating resources effectively.