Abstract: Objective To investigate the recurrence of pulmonary tuberculosis (TB) within a six-year follow-up period among patients who successfully completed treatment in Xishuangbanna in 2017, and to explore the association between various influencing factors and TB recurrence. Methods A cohort of 1 249 patients who successfully completed treatment for pulmonary tuberculosis in Xishuangbanna in 2017 was identified from the Tuberculosis Information Management System. The recurrence density was calculated across different demographic characteristics, and the Log-rank test was employed for statistical analysis. Subsequently, a Cox regression analysis was utilized to identify independent risk factors for recurrence within the six-year period. Propensity score matching (PSM) was performed to adjust for the effect of age, after which the hazard ratios (HR) for the identified independent risk factors were recalculated. Results Among the 1 249 successfully treated patients, 78 experienced recurrence within six years, yielding a recurrence rate of 6.25% and a recurrence density of 0.314 per 100 person-years. The median time to recurrence was 37.28 months. Both the Log-rank test and univariate Cox regression analysis indicated that advanced age, occupation as a farmer, retreatment status, positive etiological classification, and the presence of pulmonary cavities were associated with a higher risk of TB recurrence. Multivariate Cox regression analysis revealed that advanced age and the presence of pulmonary cavities were independent risk factors for recurrence. Following PSM adjustment for age, the HR for the presence of pulmonary cavities was 1.895 (95% CI: 1.589-3.872; P<0.01). Conclusions A notable probability of recurrence exists within six years following successful treatment for pulmonary tuberculosis, with patients presenting with cavitary pulmonary tuberculosis exhibiting a significantly higher risk. The number of recurrence cases in the current study is limited; therefore, the confirmation of additional influencing factors necessitates larger-scale, longer-term follow-up studies.

Key words: Pulmonary tuberculosis, Recurrence, Influencing factors