Abstract
BACKGROUND AND AIM: Ischemic heart disease (IHD) remains a critical global public health challenge, yet comparative studies on its burden between younger (20-54 years) and older (55+ years) adults are limited. This study aims to quantify differential IHD burden trajectories across these age groups globally, thereby informing tailored prevention strategies. METHODS: Using data from the Global Burden of Disease Study 2021 (GBD), we evaluated the IHD burden through prevalence, disability-adjusted life years (DALYs), and mortality. Trends from 1990 to 2021 were analyzed via estimated annual percentage change (EAPC), and proportional risk contributions were assessed via population attribution scores. Future trends were projected for the next 30 years via a Bayesian age-period-cohort model. RESULTS: From 1990 to 2021, the global DALY rates and mortality rates decreased, whereas the prevalence increased, particularly among younger adults (EAPC = 0.98 [0.93-1.02]). Males presented a greater IHD burden than females did. Low- and medium-socio-demographic index (SDI) regions experienced greater disease burdens than high-SDI regions did (EAPC = 1.63 [1.57-1.68]). Metabolic and behavioral risk factors, including high low-density lipoprotein (LDL) cholesterol (52.74%) and tobacco use (33.90%), are predominant among younger adults, whereas older adults face greater risks from high blood pressure (53.74%) and elevated fasting glucose (16.88%). Projections suggest that mortality will decline in both age groups (20-54 years: 22.92/100,000 population [95% UI: 17.73-28.11]; ≥ 55 years: 404.28/100,000 population [95% UI: 274.18-534.35]), whereas the prevalence will stabilize in older adults but rise and later decline in younger populations. CONCLUSION: The global IHD burden was associated with decreasing mortality and DALY rates but increasing prevalence, with notable disparities by gender, SDI, and region. Prioritizing age-specific and targeted interventions is crucial to reversing the prevalence trend and sustaining mortality reductions, ultimately mitigating the global IHD burden.