The burden of severe chest injuries in five East Asian countries: a secondary age-period-cohort analysis of GBD 2023.

BACKGROUND: Severe chest injury contributes a significant public-health burden globally; however, comprehensive assessments of its long-term trends and determinants in East Asia are lacking. This study aims to analyze the temporal patterns, key drivers, and future projections of severe chest injury burden across five East Asian countries from 1990 to 2023. METHODS: Utilizing Global Burden of Disease (GBD) 2023 data, we analyzed the epidemiology of severe chest injury in East Asia. The analysis included joinpoint regression for trend detection, age-period-cohort (APC) modeling to disentangle effects, and autoregressive integrated moving average (ARIMA) models for forecasting future trajectories. RESULTS: Across the five East Asian countries, the number of incident cases of severe chest trauma decreased from 2,420,522 in 1990 to 2,319,660 in 2023. National trends, however, diverged significantly. The age-standardized incidence rate (ASIR) significantly increased in China [estimated annual percentage change (EAPC) =0.35, 95% confidence interval (CI): 0.01 to 0.69] and the Democratic People's Republic of Korea (DPRK) (EAPC =0.61, 95% CI: 0.54 to 0.68), whereas significant decreases were observed in Japan (EAPC =-0.87, 95% CI: -0.95 to -0.79), Mongolia (EAPC =-0.65, 95% CI: -0.75 to -0.55), and the Republic of Korea (ROK) (EAPC =-1.43, 95% CI: -1.52 to -1.34). The age-standardized prevalence rate (ASPR) and age-standardized years lived with disability (YLDs) rate (ASYR) showed similar trends. The APC model revealed that this national heterogeneity was driven primarily by divergent period and cohort effects. Decomposition analysis revealed that changes in case fatality and disease severity were the dominant drivers of disability-burden evolution. In China, a +162.59% contribution from worsening clinical outcomes completely offset the -378.33% contribution from population aging, resulting in a net increase in YLDs. A persistent male predominance was evident, with the male burden approximately 2-3 times higher than that of females across all age groups. Projections based on ARIMA models suggest a continuation of this regional divergence soon (2024-2028). CONCLUSIONS: The trajectory of severe chest injury burden in East Asia is not demographically predetermined but is critically shaped by modifiable periods and cohort risks, largely reflecting the efficacy of trauma prevention and care systems. The findings underscore the need for differentiated, evidence-based public health strategies and investments in trauma system quality to reduce this preventable burden.