Abstract:

Objective: To identify the determinants of adverse treatment outcomes among patients with pulmonary tuberculosis and diabetes mellitus (PTB-DM) who have rifampicin-sensitive or unknown drug resistance status in Henan Province. Methods: Medical records of patients diagnosed with pulmonary tuberculosis and diabetes mellitus (PTB-DM) in Henan Province between January 1, 2019, and December 31, 2023, were retrieved from the Tuberculosis Management Information System, a subsystem of the China Disease Prevention and Control Information System. Patients with documented drug-resistant tuberculosis, as well as those with severe comorbidities or complications, were excluded. A total of 7354 eligible patients were included in the final analysis. The cumulative treatment success rate was estimated using the Kaplan-Meier method, while the Cox proportional hazards regression model was employed to identify risk factors associated with unsuccessful treatment outcomes. Results: Among the 7354 patients included in the study, 86.1% (6329/7354) achieved successful tuberculosis treatment, while 13.9% (1025/7354) experienced adverse treatment outcomes. The cumulative treatment success rate, as estimated using the Kaplan-Meier method, was 80.7%. Multivariate Cox proportional hazards regression analysis identified several protective factors for successful anti-tuberculosis treatment in PTB-DM patients, including sputum smear negativity at the end of the second month of treatment (HR=0.388, 95%CI: 0.281-0.535), an unavailable sputum smear result (HR=0.251, 95%CI: 0.165-0.380), and the use of a six-month treatment regimen (HR=0.129, 95%CI: 0.094-0.176). Conversely, risk factors associated with adverse treatment outcomes included older age (≥65 years; HR=1.137, 95%CI: 1.002-1.290), local household registration in Henan Province (HR=1.517, 95%CI: 1.072-2.148), positive bacteriological findings (HR=1.277, 95%CI: 1.105-1.476), and delayed diagnosis (HR=1.137, 95%CI: 1.005-1.287). Conclusion: Optimizing early sputum monitoring and implementing a standardized six-month short-course anti-tuberculosis treatment regimen for PTB-DM patients can significantly reduce the risk of adverse treatment outcomes. Meanwhile, heightened vigilance is required for older adults (≥65 years), patients with positive bacteriological findings, those experiencing delays in seeking medical care, and individuals with local household registration in Henan Province, as they remain at increased risk of unfavorable treatment outcomes.

Key words: Tuberculosis, pulmonary, Diabetes mellitus, Comorbidity, Treatment outcome, Risk factors