HIV–TB co-infection in Liangshan, a resource-limited region of Southwest China: trends and implications in the context of integrated prevention, 2019–2024

Objective To analyze epidemiological trends and key factors of HIV–TB co-infection in Liangshan Yi Autonomous Prefecture (2019–2024), a resource-limited region in Southwest China, and inform integrated prevention strategies. Methods A retrospective analysis was conducted on 3,367 HIV–TB co-infected cases extracted from the National HIV/AIDS and TB surveillance systems. Records were linked via unique identifiers. Descriptive statistics and chi-square tests for trend assessed incidence trends, demographics, transmission routes, treatment outcomes, and drug resistance. Results Under the Integrated Prevention and Control of Four Diseases policy and precision prevention and control model, HIV–TB incidence declined from 12.26 to 8.76 per 100,000 ( χ ² _trend =40.459, P < 0.001), driven by high-burden counties and populations under 45 years (all P < 0.001). Patients were predominantly young males (61.10%) and farmers (92.40%). The main HIV transmission routes were heterosexual contact (48.29%) and injection drug use (41.31%), with marked sex and age disparities: injection drug use predominated in males (50.92%) and those aged 30–45 years (50.32%), while heterosexual transmission prevailed in females (77.07%) and older adults (≥ 60 years, 87.62%). Treatment success rate was 81.76%, significantly lower in the elderly (69.52%, P < 0.05). Any drug resistance (3.30%) increased from 1.54% to 3.10% ( χ ² _trend =8.481, P _trend =0.004), driven by rifampicin resistance ( χ ² _trend =9.890, P _trend =0.002). Conclusion Integrated strategies achieved initial success reducing HIV–TB incidence, particularly in high-burden areas and younger populations. Persistent challenges—stagnant incidence and poor outcomes in the elderly, high loss to follow-up (10.87%), rising drug resistance—require targeted interventions: leveraging the Yi “clan” ( Jiazhi ) system, strengthening active screening and nutritional support for older adults, optimizing drug resistance surveillance, and integrating digital health tools.