Trends in the Burden of Urinary Tract Infections and Interstitial Nephritis: China vs. Global, 1990–2021, with Projections to 2036

Bin Niu¹kangqiang weng²hu Li²linlu She²Yingbo Dai^2*ruoyun Xie^3*

• ¹Department of Pediatrics, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, China
• ²Department of Urology, The Fifth Affiliated Hospital of Sun Yat-sen University, 52 Meihua East Road, Zhuhai City, Guangdong Province, Zhuhai, China
• ³Department of Urology, Fujian Medical University Union Hospital, Fuzhou, Fujian Province, China

Urinary tract infections (UTIs) and interstitial nephritis (IN) are global public health challenges, with significant disparities in disease burden across socio-demographic levels. This study examines trends in incidence, prevalence, mortality, and disabilityadjusted life years (DALYs) for UTIs and IN from 1990 to 2021, leveraging the Global Burden of Disease (GBD) dataset and exploring their relationship with sociodemographic index (SDI).Using GBD data, we analyzed age-standardized incidence, prevalence, mortality, and DALYs for UTIs and IN globally and regionally. Statistical methods included Joinpoint regression, Age-Period-Cohort models, and decomposition analysis to quantify the contributions of demographic and epidemiological changes to disease trends. Sociodemographic disparities and risk factor attributions were assessed using inequality metrics.From 1990 to 2021, the burden of urinary tract infections (UTIs) and interstitial nephritis (IN) showed mixed trends globally. In China, age-standardized incidence rates (ASIR) dropped from 1272.60 to 1184.13 per 100,000, prevalence rates (ASPR) from 24.21 to 22.52, mortality rates (ASMR) from 0.98 to 0.48, and DALYs from 24.67 to 10.99, reflecting consistent reductions across all metrics. Globally, ASMR declined slightly, but ASIR increased from 5294.50 to 5531.88, and ASPR rose from 100.96 to 105.36. Population growth and aging drove global increases, offset by epidemiological improvements in high-SDI regions, highlighting disparities requiring targeted interventions.Despite progress in reducing mortality, disparities in UTIs and IN burden persist, particularly in low-SDI regions. Effective interventions, including improved healthcare access and targeted risk factor management, are essential to address the growing burden in vulnerable populations. These findings provide actionable insights for global health strategies to reduce inequalities in disease outcomes.