Hamadan University of Medical Sciences Journal of Research in Health Sciences 2228-7795 26 2 2026 02 21 Socioeconomic Inequality and Spatial Distribution of Drug Abuse Mortality in Iran: A National Study in 2020 e00681 e00681 10.34172/jrhs.11568 EN Hoda Arabzadeh https://orcid.org/0000-0001-5658-8390 Faezeh Heidari Seyed Saeed Hashemi Nazari Fatemeh Shahbazi https://orcid.org/0000-0003-2320-4885 Journal Article 10.34172/jrhs.11568 2025 08 23 2025 11 09 Background: Drug abuse is a public health problem that leaves morbidity, disability and premature mortality in the society. This study investigated the epidemiological features, socioeconomic disparities, and geographic distribution of drug abuse-related deaths across Iran in 2020. Study Design: An ecological study. Methods: Data on drug abuse deaths were obtained from the Iranian Legal Medicine Organization (LMO). The Theil index, between-group variance (BGV), concentration index, and concentration curve (CC) were used to assess mortality inequality. Finally, spatial inequality was analyzed using Anselin’s Local Moran’s. Results: In 2020, the drug abuse mortality rate was 49.91 per million people in Iran. Opium (24.89%), methamphetamine (21.23%), and heroin (16.58%) were the most common substances involved in this respect. High-high clusters, including Hamadan, Markazi, Lorestan, and Ilam, had high drug abuse death rates and were surrounded by similar provinces. The concentration index of 0.10 indicated higher drug-related deaths in provinces with a higher human development index (HDI). Moreover, the Theil index and BGV revealed considerable regional inequality in drug abuse mortality rates. Conclusion: Overall, drug-related deaths in Iran predominantly affected males, particularly in the 30–39 age group. Victims had low educational attainment and were self-employed. Provinces with lower HDIs, such as Kermanshah, Hamedan, and Lorestan, had the highest mortality rates. Thus, these regions need targeted prevention and treatment. Addressing the links between substance use and suicidal behavior requires integrated mental health and addiction treatment services. In addition, policymakers should prioritize educational, preventive, and treatment programs in high-risk areas.