Community-based chest X-ray screening versus symptom-based case presentation in the elderly: evidence from three...

Community-based chest X-ray (CXR) screening has been widely performed to improve tuberculosis identification in elderly populations, but comparative evidence against mode of symptom-driven case finding remains scarce.

We conducted three annual rounds of mass CXR screening among individuals aged over 60 years in Lanxi City, China, from 2021 to 2023. Tuberculosis cases identified through CXR screening were compared with concurrent, symptom-driven case presentations via routine surveillance. Restricted cubic spline and multivariable logistic regression analyses were used to examine factors associated with distinct detection pathways.

At the individual level, a total of 831 tuberculosis cases were identified through two modes. CXR mass screening detected more patients with less typical symptoms, while symptom-driven detection was more effective in females (aOR = 0.59, 95% CI 0.39-0.88), bacteriologically confirmed cases (aOR = 0.42, 95% CI 0.27-0.63), and those aged greater than 80 (aOR = 0.50, 95% CI 0.30-0.82). Age showed a nonlinear association with mass screening yield, with peak effectiveness between 60 and 66 years while no significance was found for BMI. In population-level analysis, CXR mass screening outperformed symptom-driven detection for case identification in the first round but declined and reversed by the third round. Subgroup analyses revealed potential benefits among individuals with diabetes or prior tuberculosis history, particularly within two years post-diagnosis or treatment.

Community-based CXR screening could effectively detect incremental tuberculosis cases with atypical or mild symptoms. The young-old would benefit from mass CXR screening, while more accessible services were needed for the very elderly. Elderly individuals with diabetes or prior tuberculosis history should be prioritized, with intensified monitoring within two years after diagnosis or treatment completion.