Analysis of the prevalence characteristics and risk factors of pulmonary tuberculosis combined with extrapulmonary tuberculosis in elderly patients.

To analyze the clinical features, epidemiological characteristics, risk factors, and complication characteristics of pulmonary tuberculosis (PTB) combined with extrapulmonary tuberculosis (EPTB) in elderly patients (aged > 60 years). Clinical data were collected from pathogen positive elderly patients with PTB hospitalized in a teaching hospital in Zhejiang from 2017 to 2023. We retrospectively analyzed the risk factors for complications of EPTB in elderly patients with PTB by univariate and multivariate logistic regression models. We also described the characteristics of complications in PTB with EPTB. A total of 781 PTB elderly patients were enrolled, of whom 86 (11.01%) had complicated EPTB. The most commonly invasive sites for EPTB were thoracic spine (17.53%), cervical lymph nodes (13.40%), and meninges (12.37%). 60 < aged < 80 years (OR = 2.876, 95%CI 1.290-6.412; P = 0.010), anaemia (OR = 2.212, 95%CI 1.135-3.967; P = 0.018) and osteoporosis (OR = 4.925, 95%CI 1.501-16.160; P = 0.009) were the independent risk factors for PTB with EPTB infection. PTB with EPTB had a higher proportion of multiple serous cavity effusion (19.8% vs. 12.2%) and longer hospitalisation (17 vs. 15, P = 0.004). 60 < aged < 80 years, anaemia and osteoporosis were found to be independent risk factors for PTB with EPTB in elderly patients. We compared the epidemiological and clinical characteristics of PTB with EPTB. These results are important for improving the diagnosis of EPTB, reducing complications, and improving prognosis.