Contribution of Major Antibiotic-Resistant Bacterial Pathogens to Global Mortality Over Three Decades

Introduction Antimicrobial resistance (AMR) remains a major global public health challenge, contributing substantially to mortality and disability worldwide, undermining the effective treatment of bacterial infections, and threatening decades of progress in medicine. Despite growing recognition of antimicrobial resistance as a global public health priority, further characterization of long-term mortality and disability trends, age-specific patterns, and the contributions of major bacterial pathogens and antibiotic resistance categories is needed to inform targeted prevention and control strategies. Methods We conducted a descriptive secondary analysis of published estimates of deaths and disability-adjusted life years (DALYs) attributable to bacterial antimicrobial resistance between 1990 and 2021. Estimates derived from established burden-of-disease modelling frameworks were examined to assess temporal trends, geographical differences, and the contributions of major bacterial pathogens and antibiotic resistance categories. Supplementary epidemiological and demographic information was used to contextualize the findings. Results In 2021, bacterial antimicrobial resistance was estimated to account for approximately 1.14 million deaths (95% uncertainty interval [UI]: 0.95–1.33 million) and 42.6 million disability-adjusted life years (DALYs) worldwide. Between 1990 and 2021, estimated global deaths attributable to bacterial antimicrobial resistance increased from 1,058,009 to 1,141,416 (7.9%), whereas disability-adjusted life years (DALYs) decreased from 60,908,504 to 42,556,210 (30.1%). The geographical distribution of AMR-attributable mortality was uneven, with a substantial burden observed in South Asia, the combined Southeast Asia, East Asia, and Oceania super-region, and Sub-Saharan Africa. Together, these three super-regions accounted for approximately 71.3% of global AMR-attributable deaths in 2021. Five bacterial pathogens—Staphylococcus aureus, Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, and Streptococcus pneumoniae—collectively accounted for an estimated 839,504 AMR-attributable deaths, representing approximately 73.5% of the global total in 2021. Among the antibiotic resistance categories examined in 2021, carbapenem resistance accounted for the highest estimated burden (287,438 deaths and 10.49 million DALYs), followed by fluoroquinolone resistance (232,633 deaths and 8.73 million DALYs), methicillin resistance (129,547 deaths and 3.69 million DALYs), and third-generation cephalosporin resistance (90,302 deaths and 3.84 million DALYs). Between 1990 and 2020, estimated AMR-attributable deaths among children younger than five years declined from 487,757 to 208,430 (57.3%), whereas deaths among adults aged 70 years and older increased from 274,041 to 519,960 (89.7%). These contrasting trends indicate a changing age distribution of AMR-attributable mortality, although demographic changes may have contributed to the observed differences. The burden attributable to multidrug resistance (MDR) also increased substantially between 1990 and 2021, with estimated deaths rising from 5,304 to 36,417 (approximately 6.9-fold) and disability-adjusted life years (DALYs) increasing from 211,527 to 1,304,574 (approximately 6.2-fold). Conclusions These findings highlight contrasting trends in the global burden of bacterial antimicrobial resistance between 1990 and 2021, characterized by a modest increase in attributable deaths and a substantial reduction in disability-adjusted life years (DALYs). The marked increases in both deaths and DALYs associated with multidrug resistance, together with changes in the age distribution of AMR-attributable mortality, underscore the importance of examining resistance patterns, population characteristics, and health outcomes . These findings support coordinated public health strategies that strengthen antimicrobial resistance surveillance, expand access to diagnostics and antimicrobial susceptibility.