Risk of Mortality Associated With Substance Use Disorder in Korea: A National Population-Based Study

BACKGROUND: Substance use disorder (SUD) is a major public health issue, contributing to high morbidity and mortality worldwide. In Korea, despite ongoing public health initiatives, SUD remains a significant concern, with diverse trends and risks linked to different substance types. This study investigates the mortality risk associated with SUD in South Korea using national, population-based data. METHODS: We performed a retrospective cohort analysis using data from the National Health Insurance Service (NHIS) database spanning 2008 to 2022. Three groups of incident SUD patients were identified-those with alcohol use disorder (AUD), drug use disorder (DUD), and nicotine use disorder-and tracked over time. The study evaluated incidence rates, mortality characteristics, and risk factors for each disorder group. RESULTS: Among 3,413,297 individuals, 1,114,550 were diagnosed with SUD. The mortality rate for SUD patients was significantly higher (16.8%) compared to that of non-SUD patients (10.9%). Among SUD patients who died, AUD accounted for 89.7%, representing the highest proportion. Mortality risk was especially high among lower-income individuals, those with disabilities, and those with psychiatric comorbidities. An increasing incidence of AUD and DUD was observed among women and younger adults (15-29 years), raising particular concern for these demographics. CONCLUSION: This study showed that while the incidence trends of SUD varied by sex and age, mortality risk was notably disparate across socioeconomic and demographic groups. Specifically, we observed a rising incidence of AUD among young women and significantly elevated mortality risk in this demographic, as well as in vulnerable populations. These findings suggest the need for targeted public health interventions for high-risk groups, particularly young women, and underscore the importance of improving access to treatment and support services to reduce mortality in individuals with SUD.