[Lung function characteristics and influencing factors in patients with pulmonary tuberculosis]

A proportion of patients with pulmonary tuberculosis (TB) exhibit lung function abnormalities, yet their specific characteristics and influencing factors remain unclear. This study prospectively enrolled 178 patients diagnosed with active pulmonary TB at Beijing Geriatric Hospital from January 2017 to December 2019. Chest CT examinations were performed at initial diagnosis, and pulmonary function tests were conducted during anti-TB treatment after sputum smear conversion. CT-based TB scores, lung function patterns, and factors associated with lung function impairment were analyzed. The 178 patients had a mean age of 18.0-69.0 years (37.5±15.0), and 108 (60.7%) were male. Twenty-five patients (14.0%) showed abnormal ventilatory function, including obstructive impairment in 24 (13.5%), restrictive impairment in 3 (1.7%), and mixed impairment in 2 (1.1%); 90 patients (50.6%) exhibited reduced diffusing capacity. Binary logistic regression analysis indicated that older age and higher imaging scores were independent factors associated with lung function abnormalities. Among patients with airflow obstruction, 37.5% were young or middle-aged adults and had relatively limited lesion involvement (CT score <8). Compared with male non-smokers, male smokers had poorer ventilatory function and more extensive pulmonary lesions. These findings suggest that patients with pulmonary TB present notable lung function abnormalities, mainly characterized by impaired ventilation and reduced diffusing capacity. Lung function is an important parameter that warrants careful attention and monitoring in TB patients. Those who are older or have extensive radiographic involvement are more likely to develop lung function impairment, and airflow obstruction occurring in young and middle-aged adults should receive particular clinical attention.