Global, Regional, and National Burden of Idiopathic Epilepsy: Temporal Trends and Drivers from 1990 to 2021

Background Idiopathic epilepsy (IE), a genetically influenced neurological disorder, poses a substantial global burden. This study utilizes Global Burden of Disease (GBD) data to analyze IE trends and drivers across 21 regions and 204 countries from 1990 to 2021. Methods We analyzed the incidence, mortality, and disability-adjusted life-years (DALYs) of IE using GBD 2021 data, with stratified analyses by sex, age, and Socio-demographic Index (SDI). Age-standardized rates (ASRs) were evaluated through estimated annual percentage changes (EAPCs) to assess temporal trends. A decomposition analysis was conducted to quantify the contributions of population growth, population aging, and age-specific rate changes to burden dynamics. Results Globally, IE incident cases increased by 54.3% (2.12 million in 1990 vs. 3.27 million in 2021), with modest ASIR rises (EAPC = 0.26%, 95% CI: 0.23–0.30). Mortality increased by 34.0% (from 104,358 to 139,851 deaths), yet ASMR declined (EAPC = − 0.56%, 95% CI: −0.61 to − 0.50). DALYs rose by 22.0% to 13.88 million, while ASDR fell (EAPC = − 0.60%, 95% CI: −0.64 to − 0.56). South Asia carried the highest absolute burden (602,050 cases, 41,860 deaths), whereas Eastern Sub-Saharan Africa had the highest ASMR (7.49/100,000) and ASDR (423.53/100,000). Decomposition analysis revealed that population growth accounted for 49.0% of incident case increases, while age-specific rate changes reduced mortality by 23.6%, indicating regional improvements in survival. Males exhibited higher incidence and mortality across all ages, with peak disparities seen in adolescents and older adults. Low-SDI regions faced disproportionate mortality and disability burdens despite lower ASIRs compared to their high-SDI counterparts. Conclusions The burden of idiopathic epilepsy has increased globally, driven by population growth and regional disparities. While age-standardized rates suggest progress in mortality and disability, absolute numbers highlight escalating challenges in low-SDI regions. Targeted interventions that address genetic predisposition, age-sex differences, and healthcare access are critical to reducing global inequities in the management of IE.