Abstract
Clinical indicators for pulmonary tuberculosis (PTB) among patients with community-acquired pneumonia (CAP) have been derived from studies on younger or middle-aged populations in high TB-burden countries. However, diagnostic clues specific to older adults remain insufficiently validated. This multicenter prospective observational study aimed to identify the clinical features that can help differentiate PTB from CAP among older patients. We enrolled patients aged ≥ 65 years who were diagnosed with PTB or non-TB CAP between September 2023 and September 2025. Clinical data-including demographics, symptoms, and laboratory findings, previously reported as potential discriminators of PTB-were compared between the two groups. Of 233 patients included, 57 (24%) were diagnosed with PTB. No significant difference in sex was observed between the PTB and non-TB CAP groups. The PTB group was older and had a poorer performance status than the CAP group. On multivariate logistic regression analysis, PTB was significantly and independently associated with weight loss (aOR 8.17, p < 0.001); symptoms lasting ≥ 2 weeks (aOR 5.79, p < 0.001); and absence of general fatigue (aOR 0.19, p < 0.001) and dyspnea (aOR 0.19, p = 0.002) but not with night sweats and hemoptysis. These clinical features may be valuable indicators of PTB in older adults and inform tuberculosis control strategies in regions expected to have accelerated population aging.