Di Wu, Shiying Dong, Junjie Gong, Fangbing Li, Cong Wang, Sihan Wang, Xingye Zhai, Zhen Wang, Xiaoqi Nie, Yi Wang
SAH in young adults represents a non-uniform burden-transition pattern, with declining age-standardized rates but persistent premature mortality and DALYs, higher incidence in high-SDI settings, and greater fatal and disabling burden in lower-resource settings. These findings support stronger metabolic-risk reduction in high-SDI settings and improved blood pressure screening, referral, and acute-care access in lower-resource regions.
BACKGROUND: Subarachnoid hemorrhage (SAH) disproportionately affects young adults aged 15-49 years, yet prior global studies have rarely focused on this population and may obscure age-specific patterns by combining all-age data. We therefore quantified the global burden of SAH in young adults and explored disparities by sex and socio-demographic index (SDI) level.
METHODS: Using Global Burden of Disease 2021 data from 204 countries (1990-2021), we estimated the age-standardized incidence rates (ASIR), age-standardized prevalence rates, age-standardized death rates, and age-standardized disability-adjusted life-year (DALY) rates. Temporal trends were assessed using estimated annual percentage changes and age-period-cohort models. We further evaluated cross-country disparities by SDI, examined risk attribution using population attributable fractions, projected future burden to 2050 using Bayesian age-period-cohort models, and conducted an exploratory machine learning analysis with SHapley Additive exPlanations.
RESULTS: In 2021, SAH caused 55,012 deaths and 3.19 million DALYs among young adults globally. Although the ASIR declined over time, the absolute burden remained substantial. High-SDI regions showed higher incidence, whereas lower-SDI regions bore a greater mortality and DALY burden. Males had a higher DALY burden, whereas females had higher prevalence. Metabolic risks were the leading contributors globally, while environmental and occupational risks remained more prominent in low-SDI settings. Projections suggested a continued decline in burden through 2050, although uncertainty widened after 2040.
CONCLUSION: SAH in young adults represents a non-uniform burden-transition pattern, with declining age-standardized rates but persistent premature mortality and DALYs, higher incidence in high-SDI settings, and greater fatal and disabling burden in lower-resource settings. These findings support stronger metabolic-risk reduction in high-SDI settings and improved blood pressure screening, referral, and acute-care access in lower-resource regions.