Epidemiological Characteristics and Spatiotemporal Cluster Analysis of Multidrug-Resistant and Rifampicin-Resistant Tuberculosis Among Older People — China, 2019–2025

Introduction: Multidrug-and rifampicin-resistant tuberculosis (MDR/RR-TB) in older individuals remains a significant public health challenge in China.This study evaluated the epidemiological characteristics and spatiotemporal patterns of MDR/RR-TB in individuals aged ≥65 years in China between 2019 and 2025.Methods: Data were obtained from the China Information System for Disease Control and Prevention (CISDCP).Spatiotemporal distribution and demographic characteristics of MDR/RR-TB cases in China were analyzed using descriptive epidemiological methods.Global Moran's I and local indicators of spatial association were employed to assess spatial clustering, and spatiotemporal scanning was performed using the SaTScan software to detect highrisk clusters.Results: From 2019 to 2025, 21,569 patients with MDR/RR-TB aged ≥65 years were registered across 31 provincial-level administrative divisions nationwide [1.72% of all pulmonary tuberculosis (PTB) in older patients].The notification rate of MDR/RR TB among older people declined in 2022 and then rebounded in 2025.The proportion of MDR/RR-TB among older patients with PTB increased.The patients were predominantly male (73.3%) in the 65-69-year age group.Of the cases, 46.0% were retreated, and 83.3% underwent molecular diagnostic testing.Heilongjiang and Gansu were persistent high-high cluster areas, whereas Xinjiang presented the highest risk.Spatiotemporal scanning identified significant clusters in Xinjiang, the three northeastern provinces, Chongqing-Guizhou, and Ningxia-Shaanxi-Gansu.Conclusions: The proportion of MDR/RR-TB among older patients with PTB in China increased significantly.The clusters were mainly located in the central-western and northeastern regions.We recommend strengthening drug resistance surveillance, expanding molecular testing coverage in high-risk areas, and optimizing treatment strategies for retreated patients.China is among the countries with the highest burden of drug-resistant tuberculosis globally.In 2024, newly diagnosed multidrug-resistant and rifampicinresistant tuberculosis (MDR/RR-TB) cases in China will account for approximately 7.1% of the global total and rank second worldwide (1).China's population is rapidly aging.In 2024, the number of people aged ≥65 years reached 220 million (15.6% of the total population), making China a veritable aging society.Older adults are particularly vulnerable to TB because of their declining immune function, multiple comorbidities, and prior Mycobacterium tuberculosis infections (2).MDR/RR-TB poses even greater challenges for this population, including complex treatment regimens, a high incidence of adverse reactions, and poor outcomes (3).Previous studies have focused primarily on MDR/RR-TB in the general population or in specific regions (4-6), with limited nationwide research on the epidemiological patterns and spatiotemporal distribution of drug-resistant tuberculosis in older patients.Thus, this study analyzed the epidemiological characteristics, spatial distribution, and spatiotemporal clustering of MDR/RR-TB among older adults in China from 2019 to 2025.