Global burden of noncommunicable diseases attributable to modifiable behavioral risks among adolescents and young adults aged 10-24 years, 1990-2021.

BACKGROUND: Modifiable behavioral risks are key drivers of noncommunicable diseases (NCDs) in adolescents, yet their global burden and evolving trends remain underquantified. This study provides the first comprehensive assessment of NCD-related mortality and disability attributable to behavioral risks among adolescents aged 10-24 years across countries and regions over three decades. METHODS: Using data from the Global Burden of Disease Study 2021, we estimated age-standardized disability-adjusted life years (DALYs), mortality, and summary exposure values (SEV) for NCDs attributable to drug use, alcohol use, childhood sexual abuse and bullying, unsafe sex, child and maternal malnutrition, tobacco use, and intimate partner violence. Trends were analyzed via estimated annual percentage changes (EAPC) with 95% confidence intervals (CI). RESULTS: In 2021, behavioral risk factors contributed to 23,280 (95% uncertainty intervals [UI]: 20,960-25,530) deaths and 9.0 million (95% UI: 6.3-12.6) DALYs globally. Substance use disorders (4.4 million [95% UI: 3.3-5.6]) and mental disorders (3.9 million [95% UI: 1.9-6.9]) were the leading contributors to DALYs, while substance use disorders accounted for most deaths (13,660 [95% UI: 12,880-14,500]). Between 1990 and 2021, DALYs attributable to childhood sexual abuse and bullying and intimate partner violence increased, whereas those related to alcohol use declined despite a persistent burden (2.0 million DALYs in 2021). The global SEV for tobacco showed the sharpest decline (- 26.5%), while DALYs for drug use rose in high-SDI regions (EAPC + 3.4%). Regional disparities were pronounced, with high-income North America experiencing the heaviest burden with a DALY rate of 2140 (95% UI: 1650-2680) per 100,000, while Latin America and the Caribbean saw high alcohol use among males and drug use among females. In low- and middle-income regions, increasing trends in alcohol use and childhood sexual abuse were observed. CONCLUSIONS: The burden of NCDs from behavioral risk factors in adolescents is substantial, with significant regional and gender disparities. Early interventions targeting alcohol use, drug use, and childhood abuse are critical, particularly in high-risk regions. Tailored public health policies and further research on additional risks, like diet and physical inactivity, are needed to address adolescent health comprehensively.